'use strict';
/* LiDAR map — XYZ pyramid (EPSG:3857), one L.tileLayer per visualisation.
   LOD, caching and animation are Leaflet's own: no image levels, no CSS
   rotation, no home-made mosaic. */

const UI_VERSION = "__UI_VERSION__";
const LS_KEY = 'lidarMapView_v2';
const el = (id) => document.getElementById(id);

// --- local storage ----------------------------------------------------------
// Every access goes through here: in private browsing (or with storage
// blocked) localStorage throws — the map then starts from its defaults.
function lsGet(key, fallback) {
  try {
    const raw = localStorage.getItem(key);
    return raw == null ? fallback : JSON.parse(raw);
  } catch (e) { return fallback; }
}
function lsSet(key, value) {
  try { localStorage.setItem(key, JSON.stringify(value)); } catch (e) { /* private browsing */ }
}
function lsDel(key) {
  try { localStorage.removeItem(key); } catch (e) { /* private browsing */ }
}
// --- end of storage ----------------------------------------------------------

const SVG_EYE = '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M1 12s4-8 11-8 11 8 11 8-4 8-11 8-11-8-11-8z"/><circle cx="12" cy="12" r="3"/></svg>';
const SVG_EYE_OFF = '<svg viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"><path d="M17.94 17.94A10.07 10.07 0 0 1 12 20c-7 0-11-8-11-8a18.45 18.45 0 0 1 5.06-5.94M9.9 4.24A9.12 9.12 0 0 1 12 4c7 0 11 8 11 8a18.5 18.5 0 0 1-2.16 3.19M14.12 14.12a3 3 0 1 1-4.24-4.24"/><line x1="1" y1="1" x2="23" y2="23"/></svg>';

// Display: one main layer (oriented relief) and the "precision" layer
// (ground point density), shown alone or compared: a sliding divider
// separates two layers (relief, precision or OSM only) on either side.
// P key: next mode.
const VIEW_MODES = [['relief', 'Relief'], ['precision', 'Precision'], ['compare', 'Compare']];
const VIEW_KEYS = VIEW_MODES.map(m => m[0]);
const validMode = (v) => (VIEW_KEYS.includes(v) ? v : null);
const COMPARE_SIDES = [['relief', 'Relief'], ['precision', 'Precision'], ['osm', 'OSM only']];
const validSide = (v) => (COMPARE_SIDES.some(s => s[0] === v) ? v : null);
const DEFAULT_COMPARE = { left: 'relief', right: 'precision', pos: 50 };
function validCompare(c) {
  c = c || {};
  const pos = Number(c.pos);
  return { left: validSide(c.left) || DEFAULT_COMPARE.left,
           right: validSide(c.right) || DEFAULT_COMPARE.right,
           pos: Number.isFinite(pos) ? Math.min(95, Math.max(5, pos)) : DEFAULT_COMPARE.pos };
}
// Precision levels: level k from 0.25 × 2^(k/2) pts/m²
// (visualizations.density_levels), grey = "gray" colormap over 0..15.
const PREC_LEVELS = 16;

let META = null;
let STATE = null;
// True until the panel's first render at startup: keeps a remembered Export
// tab from reframing the view over a shared link or the initial URL
// (see printSetOpen). Reset to false in both the .then() AND the .catch() of
// the /api/map/meta load (otherwise a server unreachable at startup leaves it
// stuck at true forever: the Export tab would never reframe again).
let BOOTSTRAPPING = true;

// --- theme ------------------------------------------------------------------
// auto = follows the system; ☀/☾ forces light or dark; third press: auto.
const THEME_LS = 'lidar-theme';
const THEME_NEXT = { auto: 'light', light: 'dark', dark: 'auto' };
const THEME_ICON = { auto: '◐', light: '☀', dark: '☾' };
const THEME_TITLE = { auto: 'Theme: follows the system', light: 'Theme: light', dark: 'Theme: dark' };
const darkQuery = window.matchMedia ? window.matchMedia('(prefers-color-scheme: dark)') : null;

function themeIsDark() {
  const t = document.documentElement.dataset.theme;
  return t === 'dark' || (t !== 'light' && !!(darkQuery && darkQuery.matches));
}

function applyTheme(pref) {
  const p = THEME_NEXT[pref] ? pref : 'auto';
  if (p === 'auto') delete document.documentElement.dataset.theme;
  else document.documentElement.dataset.theme = p;
  const btn = el('btnTheme');
  if (btn) { btn.textContent = THEME_ICON[p]; btn.title = THEME_TITLE[p] + ' (click to change)'; }
  if (typeof applyLayers === 'function' && STATE) applyLayers();   // dimmed OSM base map
  redrawRose();
  return p;
}

// Legend rose: its cardinal labels use the text colour, so it is redrawn
// on every theme change (if already drawn).
function redrawRose() {
  if (!drawRose.done) return;
  drawRose.done = false;
  drawRose();
}

function cssVar(name) {
  return getComputedStyle(document.documentElement).getPropertyValue(name).trim();
}
let THEME = applyTheme(lsGet(THEME_LS, 'auto'));

const LAYERS = new Map();   // key → L.TileLayer

const map = L.map('map', {
  zoomControl: false,
  attributionControl: true,
  minZoom: 3,
  // Zoom capped at native (19 = 0.2 m/px, 1 screen px = 1 LiDAR px): the whole
  // pyramid is generated in advance, never an upscaled or stretched tile.
  maxZoom: 19,
  zoomSnap: 0.5,
  wheelPxPerZoomLevel: 90,
  worldCopyJump: false,
  preferCanvas: false
});
map.attributionControl.setPrefix('');
L.control.scale({ metric: true, imperial: false, position: 'bottomleft' }).addTo(map);

// During the zoom animation, transforms ONLY (no level created, tiles loaded
// at the end): Chrome does not composite a fresh level (empty at first, it is
// animated on the main thread, frozen ~90 ms by loading). The base map jumped
// while the oriented relief, which keeps its even level, slid smoothly — the
// two layers went out of sync. Leaflet 1.9 also fires "zoom" at the START of
// the animation: same guard in _resetView while the map is animating.
const ZoomAnimTileLayer = L.TileLayer.extend({
  _animateZoom(e) { this._setView(e.center, e.zoom, true, true); },
  _resetView(e) {
    if (this._map && this._map._animatingZoom) {
      this._setView(this._map.getCenter(), this._map.getZoom(), true, true);
      return;
    }
    L.TileLayer.prototype._resetView.call(this, e);
  }
});

// --- tile loading -----------------------------------------------------------
// The counter is recomputed from the actual state of each layer's tiles
// (current-level tiles not loaded yet) rather than +1/−1 on events: a tile
// removed before it finishes loading (fast panning) fires neither "tileload"
// nor "tileerror", so an event-based counter would drift. Batch: from the
// first pending tile back to zero; the bar shows the share of the batch
// already loaded.
const TILE_LOAD = { layers: new Set(), batch: 0, done: 0, raf: 0, hideT: 0 };

function tilesPending() {
  let n = 0;
  for (const layer of TILE_LOAD.layers) {
    if (!layer._map) continue;
    for (const key in layer._tiles) {
      const t = layer._tiles[key];
      if (t.current && !t.loaded) n += 1;
    }
  }
  return n;
}

function updateTileLoad() {
  TILE_LOAD.raf = 0;
  const box = el('tileload');
  if (!box) return;
  const pending = tilesPending();
  if (pending > 0) {
    clearTimeout(TILE_LOAD.hideT);
    TILE_LOAD.hideT = 0;
    if (TILE_LOAD.batch === 0) TILE_LOAD.done = 0;
    TILE_LOAD.batch = Math.max(TILE_LOAD.batch, TILE_LOAD.done + pending);
    el('tileloadText').textContent = pending + (pending > 1 ? ' tiles left' : ' tile left');
    el('tileloadBar').style.width = Math.round(100 * TILE_LOAD.done / TILE_LOAD.batch) + '%';
    box.classList.remove('done');
    box.hidden = false;
  } else if (TILE_LOAD.batch > 0 && !TILE_LOAD.hideT) {
    TILE_LOAD.batch = 0;
    el('tileloadText').textContent = 'View loaded';
    el('tileloadBar').style.width = '100%';
    box.classList.add('done');
    TILE_LOAD.hideT = setTimeout(() => { box.hidden = true; TILE_LOAD.hideT = 0; }, 600);
  }
}

function scheduleTileLoad() {
  if (!TILE_LOAD.raf) TILE_LOAD.raf = requestAnimationFrame(updateTileLoad);
}

ZoomAnimTileLayer.addInitHook(function () {
  TILE_LOAD.layers.add(this);
  const onDone = () => { TILE_LOAD.done += 1; scheduleTileLoad(); };
  this.on('tileload', onDone);
  this.on('tileerror', onDone);
  this.on('tileloadstart tileunload load add remove', scheduleTileLoad);
});

const base = new ZoomAnimTileLayer('https://tile.openstreetmap.org/{z}/{x}/{y}.png', {
  // Class set at creation from the current theme (not a hard-coded "dark"):
  // otherwise the base map flashes dark in the light theme until /api/map/meta
  // answers (and stays dark if the call fails). applyLayers() corrects it later.
  maxZoom: 19, maxNativeZoom: 19, keepBuffer: 2, className: themeIsDark() ? 'base-dark' : '',
  // Otherwise _setView recreates a level mid-animation despite noUpdate.
  updateWhenZooming: false,
  attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a>'
}).addTo(map);

function toast(msg, ms) {
  const t = el('toast');
  t.textContent = msg;
  t.hidden = false;
  clearTimeout(toast._t);
  toast._t = setTimeout(() => { t.hidden = true; }, ms || 3500);
}

// --- persisted state ------------------------------------------------------
function precisionKey() {
  const p = META && META.precision_layer;
  return p && META.layers.some(l => l.key === p) ? p : null;
}

function mainKeys(meta) {
  return meta.layers.map(l => l.key).filter(k => k !== meta.precision_layer);
}

function validMain(meta, k) {
  return mainKeys(meta).includes(k) ? k : null;
}

// Relief intensity: contrast applied to the main layer's container (a
// personal comfort setting, never saved as a server default nor applied to
// the exported PDF).
function clampIntensity(v) {
  const n = Number(v);
  return Number.isFinite(n) ? Math.round(Math.min(2, Math.max(0.5, n)) * 10) / 10 : 1;
}
const fmtIntensity = (v) => String(v) + '×';

function defaultState(meta) {
  const b = meta.default_base || {};
  return {
    main: validMain(meta, meta.default_main) || mainKeys(meta)[0] || null,
    mode: validMode(meta.default_mode) || 'relief',
    compare: validCompare(null),
    intensity: 1,
    base: { on: b.on !== undefined ? !!b.on : true,
            opacity: b.opacity !== undefined ? Number(b.opacity) : 0.85,
            // null = follows the theme (explicit choice only if b.dark is
            // already a boolean set server-side).
            dark: b.dark == null ? null : !!b.dark },
  };
}

function loadState(meta) {
  const def = defaultState(meta);
  let st = def;
  const s = lsGet(LS_KEY, null);
  if (s) {
    // Old format (before v3): the former webapp persisted base.dark:true on
    // every save, never a real user choice — ignored here (the base map then
    // follows the theme); only v3 writes an explicit dark (see saveState).
    const sBase = Object.assign({}, s.base || {});
    if (s.v !== 3) delete sBase.dark;
    st = { main: validMain(meta, s.main) || def.main,
           // Old remembered "both" mode (product of the layers): relief.
           mode: validMode(s.mode === 'both' ? 'relief' : s.mode) || def.mode,
           compare: validCompare(s.compare),
           intensity: clampIntensity(s.intensity),
           base: Object.assign({}, def.base, sBase) };
  }
  // Shared link: takes precedence over the local state (old &L=… links from
  // the layer stack are ignored, the view then opens on the current state).
  const hash = parseHash();
  if (hash) {
    if (hash.main && validMain(meta, hash.main)) st.main = hash.main;
    if (hash.view) st.mode = hash.view.mode;
    if (hash.compare) st.compare = hash.compare;
    if (hash.base) st.base = hash.base;
    if (hash.intensity != null) st.intensity = hash.intensity;
    // Full link (layer or mode in the hash) without &I: the link export only
    // writes &I when ≠ 1 (viewHash), so its absence means 1×, never the
    // comfort intensity left in this browser's localStorage.
    else if (hash.main || hash.view) st.intensity = 1;
  }
  return st;
}

function saveState() {
  // v: 3 marks a format where base.dark, when set, is a real user choice
  // (see loadState) — never mixed into STATE itself.
  lsSet(LS_KEY, Object.assign({ v: 3 }, STATE));
}

// --- view hash ------------------------------------------------------------
// #z/lat/lng&M=main&P=mode&C=left:right:position&B=on:opacity:dark&I=intensity
function parseHash() {
  const m = /^#([\d.]+)\/(-?[\d.]+)\/(-?[\d.]+)(.*)$/.exec(location.hash || '');
  if (!m) return null;
  const out = { zoom: parseFloat(m[1]), lat: parseFloat(m[2]), lng: parseFloat(m[3]),
                main: null, view: null, compare: null, base: null, intensity: null };
  const seg = {};
  for (const part of m[4].split('&')) {
    const i = part.indexOf('=');
    if (i > 0) seg[part.slice(0, i)] = part.slice(i + 1);
  }
  if (seg.M) out.main = seg.M;
  if (seg.I) out.intensity = clampIntensity(seg.I);
  if (seg.P) {
    const f = seg.P.split(':');
    // Old "both" mode (product of the layers): opens as relief. The opacity
    // that followed it (P=mode:opacity) is ignored.
    const mode = validMode(f[0] === 'both' ? 'relief' : f[0]);
    if (mode) out.view = { mode };
  }
  if (seg.C) {
    const f = seg.C.split(':');
    out.compare = validCompare({ left: f[0], right: f[1], pos: f[2] });
  }
  if (seg.B) {
    const f = seg.B.split(':');
    if (f.length === 3) {
      const o = Number(f[1]);
      out.base = { on: f[0] === '1', opacity: Number.isFinite(o) ? o / 100 : 0.85, dark: f[2] === '1' };
    }
  }
  return out;
}

function viewHash(full) {
  const c = map.getCenter();
  let h = '#' + map.getZoom().toFixed(1) + '/' + c.lat.toFixed(6) + '/' + c.lng.toFixed(6);
  if (full) {
    if (STATE.main) h += '&M=' + STATE.main;
    h += '&P=' + STATE.mode;
    if (STATE.mode === 'compare') {
      h += '&C=' + STATE.compare.left + ':' + STATE.compare.right + ':' + Math.round(STATE.compare.pos);
    }
    const dark = STATE.base.dark === null || STATE.base.dark === undefined ? themeIsDark() : STATE.base.dark;
    h += '&B=' + (STATE.base.on ? '1' : '0') + ':' + Math.round(STATE.base.opacity * 100)
       + ':' + (dark ? '1' : '0');
    if (STATE.intensity !== 1) h += '&I=' + STATE.intensity;
  }
  return h;
}

let hashTimer = null;
function saveHashSoon() {
  clearTimeout(hashTimer);
  hashTimer = setTimeout(() => {
    history.replaceState(null, '', location.pathname + location.search + viewHash(false));
  }, 350);
}

// --- layers ---------------------------------------------------------------
function tileUrl(key) {
  return META.tile_url.replace('{layer}', key) + (META.stamp ? '?v=' + META.stamp : '');
}

// Layer with even standard levels only (reduced server-side storage): at an
// odd zoom, tiles from the NEXT even level up are shown scaled down by half
// (sharp). Exception: the native level itself (19, odd — 0.2 m/px) is
// requested as is, rendered on the fly by the server. Folding it onto the
// lower even level capped the display at 0.4 m/px, then stretched by the
// browser: full resolution was never seen. Beyond native, Leaflet stretches
// the native level (never an upscaled tile server-side). The Leaflet tile
// level here is the standard numbering (zoomOffset −1 with 512 px tiles).
const EvenLevelTileLayer = ZoomAnimTileLayer.extend({
  _clampZoom(zoom) {
    let z = L.TileLayer.prototype._clampZoom.call(this, zoom);
    const maxN = this.options.maxNativeZoom;
    if (this.options.evenLevels && z % 2 && (maxN === undefined || z < maxN)) z += 1;
    return z;
  }
});

function buildLayers() {
  // Shared LiDAR stack (z 400). Panes are reused if already created
  // (refresh after a generation run).
  const stack = map.getPane('lidarStack') || map.createPane('lidarStack');
  stack.style.zIndex = 400;
  META.layers.forEach((info) => {
    const paneName = 'lidar-' + info.key;
    const pane = map.getPane(paneName) || map.createPane(paneName, stack);
    const existing = LAYERS.get(info.key);
    if (existing) { if (map.hasLayer(existing)) map.removeLayer(existing); }
    const layer = new EvenLevelTileLayer(tileUrl(info.key), {
      evenLevels: !!META.even_levels,
      pane: paneName,
      // Tile coverage: Leaflet requests no tile outside it — no useless
      // requests for the rest of the world.
      bounds: META.bounds
        ? L.latLngBounds([META.bounds[1], META.bounds[0]], [META.bounds[3], META.bounds[2]])
        : undefined,
      tileSize: META.tile_size,
      zoomOffset: META.zoom_offset,
      minNativeZoom: META.min_zoom,
      maxNativeZoom: META.max_native_zoom,
      minZoom: 0,
      maxZoom: 19,
      // 512 px tiles: one off-screen buffer row equals the base map's two
      // 256 px rows. Two rows doubled the decoded images kept in memory
      // (1 MB each) for little gain.
      keepBuffer: 1,
      updateWhenZooming: false,
      crossOrigin: false,
      errorTileUrl: 'data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7',
      attribution: META.attribution
    });
    // The tile container only exists once added: the comparison clip is
    // applied to it at that point.
    layer.on('add', applyCompareClip);
    LAYERS.set(info.key, layer);
  });
  applyLayers();
}

// Mode actually applied: without a served precision layer, relief only.
function effectiveMode() {
  return precisionKey() ? STATE.mode : 'relief';
}

// Layer shown on one side of the comparison (null = OSM only).
function sideLayerKey(side) {
  return side === 'relief' ? STATE.main : side === 'precision' ? precisionKey() : null;
}

function applyLayers() {
  const prec = precisionKey();
  const mode = effectiveMode();
  const wanted = new Set(
    mode === 'relief' ? [STATE.main]
    : mode === 'precision' ? [prec]
    : [sideLayerKey(STATE.compare.left), sideLayerKey(STATE.compare.right)]);
  for (const [key, layer] of LAYERS) {
    const pane = map.getPane('lidar-' + key);
    if (pane) pane.style.zIndex = key === prec ? '402' : '401';
    if (wanted.has(key)) { if (!map.hasLayer(layer)) layer.addTo(map); layer.setOpacity(1); }
    else if (map.hasLayer(layer)) map.removeLayer(layer);
  }
  if (STATE.base.on) { if (!map.hasLayer(base)) base.addTo(map); }
  else if (map.hasLayer(base)) map.removeLayer(base);
  base.setOpacity(STATE.base.opacity);
  const container = base.getContainer && base.getContainer();
  const dark = STATE.base.dark === null || STATE.base.dark === undefined ? themeIsDark() : STATE.base.dark;
  if (container) container.classList.toggle('base-dark', dark);
  // Intensity (contrast): set on the relief layer's container only — the
  // comparison clip (clipPath) stays independent, both CSS properties
  // coexist on the same container.
  for (const [key, layer] of LAYERS) {
    const c = layer.getContainer && layer.getContainer();
    if (c) c.style.filter = key === STATE.main && STATE.intensity !== 1 ? 'contrast(' + STATE.intensity + ')' : '';
  }
  applyCompareClip();
  updateRose();
}

// Divider range, in px of the map container: the handle stays within the
// visible part of the map, never under the panel (desktop: open panel or
// icon strip, full height) nor under the tool column.
// COMPARE_MARGIN = half the handle width + margin.
const COMPARE_MARGIN = 24;
function compareBounds() {
  const r = map.getContainer().getBoundingClientRect();
  let min = COMPARE_MARGIN, max = r.width - COMPARE_MARGIN;
  if (!isPhone()) {
    min = Math.max(min, el('panel').getBoundingClientRect().right - r.left + COMPARE_MARGIN);
    max = Math.min(max, el('tools').getBoundingClientRect().left - r.left - COMPARE_MARGIN);
  }
  // Window too narrow: the divider stays in the middle of the range.
  if (min > max) min = max = (min + max) / 2;
  return { left: r.left, min, max };
}

// Clip the layers on either side of the divider, in layer coordinates (the
// tile containers move with the map): recomputed on every move. Same layer
// on both sides: no clip. STATE.compare.pos keeps the requested value (link,
// drag); the displayed divider, bar and clip together, is bounded by
// compareBounds(). Mode other than "compare" and layers already unclipped:
// nothing to do. Without this guard, every map move (map.on('move', …))
// re-reads and rewrites the style of every layer just to set empty
// clip-paths, on every frame, even when Compare has never been opened.
let compareClipsCleared = true;
function applyCompareClip() {
  if (!STATE) return;
  const on = effectiveMode() === 'compare';
  if (!on && compareClipsCleared) { el('compareBar').hidden = true; return; }
  el('compareBar').hidden = !on;
  const size = map.getSize();
  let x = size.x * (on ? STATE.compare.pos : 50) / 100;
  const bounds = on ? compareBounds() : null;
  if (bounds) x = Math.min(bounds.max, Math.max(bounds.min, x));
  const nw = map.containerPointToLayerPoint([0, 0]);
  const se = map.containerPointToLayerPoint(size);
  const cx = map.containerPointToLayerPoint([x, 0]).x;
  const leftKey = sideLayerKey(STATE.compare.left), rightKey = sideLayerKey(STATE.compare.right);
  for (const [key, layer] of LAYERS) {
    const c = layer.getContainer && layer.getContainer();
    if (!c) continue;
    let clip = '';
    if (on && leftKey !== rightKey) {
      if (key === leftKey) clip = `polygon(${nw.x}px ${nw.y}px, ${cx}px ${nw.y}px, ${cx}px ${se.y}px, ${nw.x}px ${se.y}px)`;
      else if (key === rightKey) clip = `polygon(${cx}px ${nw.y}px, ${se.x}px ${nw.y}px, ${se.x}px ${se.y}px, ${cx}px ${se.y}px)`;
    }
    c.style.clipPath = clip;
  }
  compareClipsCleared = !on;
  if (on) el('compareBar').style.left = (bounds.left + x) + 'px';
}
map.on('move', applyCompareClip);
map.on('resize zoomend', applyCompareClip);
// Panel collapsed, expanded, sheet resized: the divider range changes.
document.addEventListener('panel:tab', applyCompareClip);

(function compareDrag() {
  const bar = el('compareBar');
  let dragging = false;
  bar.addEventListener('pointerdown', (e) => { dragging = true; bar.setPointerCapture(e.pointerId); e.preventDefault(); });
  bar.addEventListener('pointermove', (e) => {
    if (!dragging) return;
    const b = compareBounds();
    const x = Math.min(b.max, Math.max(b.min, e.clientX - b.left));
    STATE.compare.pos = Math.min(95, Math.max(5, 100 * x / map.getSize().x));
    applyCompareClip();
  });
  const end = () => { if (dragging) { dragging = false; saveState(); } };
  bar.addEventListener('pointerup', end);
  bar.addEventListener('pointercancel', end);
})();

function setMode(mode, announce) {
  if (!validMode(mode)) return;
  STATE.mode = mode;
  saveState(); renderPanel(); applyLayers();
  if (announce) toast('Display: ' + VIEW_MODES.find(m => m[0] === mode)[1], 1200);
}

function renderPrecLegend() {
  const bar = el('precBar');
  if (bar.childElementCount) return;
  for (let k = 0; k < PREC_LEVELS; k++) {
    const g = Math.round(255 * k / (PREC_LEVELS - 1));
    const lo = 0.25 * Math.pow(2, k / 2);
    const hi = 0.25 * Math.pow(2, (k + 1) / 2);
    const cell = document.createElement('i');
    cell.style.background = 'rgb(' + g + ',' + g + ',' + g + ')';
    cell.title = k === 0 ? '≤ ' + hi.toFixed(2) + ' pts/m²'
      : k === PREC_LEVELS - 1 ? '≥ ' + Math.round(lo) + ' pts/m²'
      : lo.toFixed(lo < 10 ? 1 : 0) + '–'
        + hi.toFixed(hi < 10 ? 1 : 0) + ' pts/m²';
    bar.appendChild(cell);
  }
}

// "How to read": sentences from VIZ_LEGENDS (reading field), served by
// /api/map/meta — same text as the PDF sheet legend.
function renderReading() {
  const mode = effectiveMode();
  const keys = mode === 'precision' ? [precisionKey()]
    : mode === 'compare' ? [sideLayerKey(STATE.compare.left), sideLayerKey(STATE.compare.right)]
    : [STATE.main];
  const seen = new Set();
  const items = [];
  for (const k of keys) {
    if (!k || seen.has(k)) continue;
    seen.add(k);
    const info = META.layers.find(l => l.key === k);
    for (const s of (info && info.reading) || []) items.push('<li>' + esc(s) + '</li>');
  }
  el('readingList').innerHTML = items.join('');
  el('readingBlock').hidden = !items.length;
}

function renderPanel() {
  const labels = new Map(META.layers.map(l => [l.key, l]));
  const mains = mainKeys(META);
  const info = labels.get(STATE.main);
  const name = el('mainName'), sel = el('mainSel');
  name.textContent = info ? info.label : 'No layer';
  name.title = info ? (info.description || info.label) : '';
  // Several possible main layers: a menu; otherwise a plain label.
  const many = mains.length > 1;
  name.hidden = many;
  sel.hidden = !many;
  if (many) {
    sel.innerHTML = mains.map(k => '<option value="' + k + '"' + (k === STATE.main ? ' selected' : '')
      + '>' + labels.get(k).label + '</option>').join('');
  }
  const prec = precisionKey();
  el('precBlock').hidden = !prec;
  el('reliefIntensity').value = STATE.intensity;
  el('reliefIntensityVal').textContent = fmtIntensity(STATE.intensity);
  el('intensityRow').hidden = effectiveMode() === 'precision';
  renderReading();
  if (!prec) return;
  renderPrecLegend();
  const mode = effectiveMode();
  el('modeSeg').querySelectorAll('button').forEach(b =>
    b.setAttribute('aria-pressed', String(b.dataset.mode === mode)));
  el('compareCtl').hidden = mode !== 'compare';
  for (const [id, side] of [['compareLeft', 'left'], ['compareRight', 'right']]) {
    const sel = el(id);
    sel.innerHTML = COMPARE_SIDES.map(([k, lbl]) => '<option value="' + k + '"'
      + (k === STATE.compare[side] ? ' selected' : '') + '>' + lbl + '</option>').join('');
  }
  el('precLegend').hidden = mode === 'relief'
    || (mode === 'compare' && STATE.compare.left !== 'precision' && STATE.compare.right !== 'precision');
}

function renderBaseRow() {
  const b = STATE.base;
  const toggle = el('baseToggle');
  toggle.classList.toggle('on', b.on);
  toggle.innerHTML = b.on ? SVG_EYE : SVG_EYE_OFF;
  el('baseOpacity').value = Math.round(b.opacity * 100);
  el('basePct').textContent = Math.round(b.opacity * 100) + '%';
  el('baseRow').classList.toggle('on', b.on);
}

// --- tile card ------------------------------------------------------------
let tileSel = null;                 // outline of the selected tile

function esc(v) {
  return String(v == null ? '' : v).replace(/[&<>"]/g, c => ({ '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;' }[c]));
}

function fmtDate(v, withTime) {
  if (!v) return '—';
  const d = new Date(v);
  if (isNaN(d)) return esc(v);
  const opt = withTime ? { dateStyle: 'long', timeStyle: 'short', timeZone: 'Europe/Paris' }
                       : { dateStyle: 'long', timeZone: 'Europe/Paris' };
  return d.toLocaleString('en-GB', opt);
}

function fmtDensity(q) {
  if (!q || q.ground_density == null) return 'not available';
  return q.ground_density.toFixed(q.ground_density < 10 ? 1 : 0) + ' ground pts/m²';
}

function fmtAcq(q) {
  if (!q || !q.acq_start) return 'not available';
  return q.acq_end && q.acq_end.slice(0, 10) !== q.acq_start.slice(0, 10)
    ? fmtDate(q.acq_start) + ' → ' + fmtDate(q.acq_end) : fmtDate(q.acq_start);
}

function kv(rows) {
  return '<dl class="info-kv">' + rows.filter(r => r[1] != null && r[1] !== '')
    .map(r => '<dt>' + r[0] + '</dt><dd>' + r[1] + '</dd>').join('') + '</dl>';
}

function selectTileOutline(data) {
  if (tileSel) { map.removeLayer(tileSel); tileSel = null; }
  if (!data || !data.corners) return;
  // Dedicated pane above the LiDAR stack: in the default overlayPane
  // (z-index 400, like lidarStack), the outline went under the tiles.
  tileSel = L.polygon(data.corners, { pane: 'tileSel', color: cssVar('--tile-sel'), weight: 2,
                                      fill: false, dashArray: '6 4',
                                      interactive: false }).addTo(map);
}

function ignSection(ign) {
  if (!ign) return '<div class="meta">Loading IGN information…</div>';
  if (ign.error) return '<div class="meta">IGN catalogue unreachable for now.</div>';
  if (!ign.found) return '<div class="meta">Tile not published by IGN (outside LiDAR HD coverage or not released yet).</div>';
  const start = ign.acquisition_start, end = ign.acquisition_end;
  let when = fmtDate(start, true);
  if (start && end && String(start).slice(0, 10) === String(end).slice(0, 10) && String(end).length > 10) {
    when = fmtDate(start, true) + ' → ' + new Date(end).toLocaleTimeString('en-GB',
      { hour: '2-digit', minute: '2-digit', timeZone: 'Europe/Paris' });
  } else if (end && String(end).slice(0, 10) !== String(start || '').slice(0, 10)) {
    when = fmtDate(start) + ' → ' + fmtDate(end);
  }
  const pts = ign.points ? Number(ign.points).toLocaleString('en-GB') + ' points' : null;
  return kv([
    ['LiDAR scan', when],
    ['Sensor', (ign.sensors || []).map(esc).join('<br>')],
    ['Mission', esc(ign.mission)],
    ['Acquisition', [ign.acquisition_operator, ign.acquisition_owner && ('for ' + ign.acquisition_owner)]
                    .filter(Boolean).map(esc).join(' ')],
    ['IGN release', ign.edition_date ? fmtDate(ign.edition_date) : null],
    ['Classification', esc(ign.classification_process)],
    ['Point cloud', pts],
  ]) + (ign.download_url
    ? '<a class="info-dl" href="' + esc(ign.download_url) + '" target="_blank" rel="noopener">⤓ Download the IGN LiDAR point cloud (.copc.laz)</a>'
    : '') + (ign.stac_url
    ? '<div class="meta"><a href="' + esc(ign.stac_url) + '" target="_blank" rel="noopener">Catalogue record</a></div>' : '');
}

function calageSection(c) {
  if (!c || !c.beams || !c.beams.length) return '';
  const offs = Object.entries(c.offsets_cm || {}).map(([k, v]) => k + ': ' + (v > 0 ? '+' : '') + String(v) + ' cm');
  const lines = Object.values(c.lines_rms_cm || {});
  return '<div class="info-sec"><h4>Vertical alignment of flight strips</h4>' + kv([
    ['Strips', c.beams.length + ' (PSID ' + c.beams.map(esc).join(', ') + ')'],
    ['Offsets', offs.length ? offs.join('<br>') : 'none ≥ 0.5 cm'],
    ['Scan lines', lines.length ? 'corrected, at most ' + String(Math.max(...lines)) + ' cm RMS' : null],
  ]) + '</div>';
}

function renderTileCard(data, ign) {
  const regenBtn = (GEN.available && GEN.allowed)
    ? '<div class="row"><button id="tileRegen" class="btn" title="Add this tile to the generation selection (IGN download + processing)">↻ ' + (data.found ? 'Regenerate' : 'Generate') + ' this tile</button></div>'
    : '';
  el('tileTitle').textContent = 'Tile ' + data.col + ' · ' + data.row;
  const bb = data.l93_bbox || [];
  let html = '<div class="meta"><b>' + esc(data.name) + '</b></div>' +
    '<div class="info-sec"><h4>Extent</h4>' + kv([
      ['Lambert 93', bb.length ? 'X ' + bb[0].toLocaleString('en-GB') + ' – ' + bb[2].toLocaleString('en-GB') +
                                '<br>Y ' + bb[1].toLocaleString('en-GB') + ' – ' + bb[3].toLocaleString('en-GB') : null],
      ['Area', '1 km × 1 km'],
    ]) + '</div>' +
    '<div class="info-sec"><h4>LiDAR acquisition (IGN)</h4>' + ignSection(ign) + '</div>';
  if (data.found) {
    const viz = (data.layers || []).map(k => {
      const info = META.layers.find(l => l.key === k);
      return info ? info.label : k;
    }).join(', ');
    html += '<div class="info-sec"><h4>Rendering</h4>' + kv([
      ['Resolution', String(data.resolution) + ' m/px'],
      ['Classification', esc(data.method || 'unknown')],
      ['Generated', esc(data.generated || '—')],
      ['Layers', esc(viz || '—')],
    ]) + '</div>' + calageSection(data.calage);
  } else {
    html += '<div class="info-sec"><div class="meta">No rendering on this tile yet.</div></div>';
  }
  el('tileBody').innerHTML = html + regenBtn;
  const btn = el('tileRegen');
  if (btn) btn.addEventListener('click', genAddCellFromQuery);
}

function showTileInfo(data, latlng) {
  lastTileQuery = latlng || lastTileQuery;
  if (!data) {
    el('tileTitle').textContent = 'Tile';
    el('tileBody').innerHTML = '<div class="meta">Server unreachable: try again in a moment.</div>';
    return;
  }
  renderTileCard(data, null);
  // IGN details fetched separately: the selection shows without waiting for the catalogue.
  const key = data.col + '_' + data.row;
  showTileInfo.current = key;
  fetch('api/map/ign?col=' + data.col + '&row=' + data.row)
    .then(r => r.ok ? r.json() : { error: 'HTTP ' + r.status })
    .catch(() => ({ error: 'network' }))
    .then(ign => { if (showTileInfo.current === key) renderTileCard(data, ign); });
}

let SELECTED_TILE = null;          // data of the selected tile (or null)

// The tab label stays "Tile" (5 tabs in 340 px: a variable label would
// overflow); col · row goes into the tab's title (hover) and into
// #tileTitle, always readable in the card itself.
function tileTabTitle() {
  return (SELECTED_TILE ? 'Tile ' + SELECTED_TILE.col + ' · ' + SELECTED_TILE.row : 'Tile') + ' (2)';
}

// Refreshes the Tile tab (title + hint/card toggle) whether it is visible or
// not: its content must be up to date as soon as it is opened.
function renderTabTile() {
  document.querySelector('button[data-tab="tile"]').title = tileTabTitle();
  el('tileHint').hidden = !!SELECTED_TILE;
  el('tileCard').hidden = !SELECTED_TILE;
  if (SELECTED_TILE) showTileInfo(SELECTED_TILE, lastTileQuery);
}

// Selects a tile (outline + card in the Tile tab) without changing the
// displayed tab.
function selectTile(data, latlng) {
  lastTileQuery = latlng || lastTileQuery;
  SELECTED_TILE = data;
  selectTileOutline(data);
  renderTabTile();
}

// Deselects (click on the same tile again, Escape): removes the outline and
// puts the Tile tab back on its hint.
function clearTileSelection() {
  SELECTED_TILE = null;
  if (tileSel) { map.removeLayer(tileSel); tileSel = null; }
  renderTabTile();
}

// --- oriented-relief compass rose ------------------------------------------
// Same colours as visualizations._relief_lut: CIELAB hue = orientation
// (aspect = compass bearing + 90°, the renderer's arctan2(dy, dx) frame),
// chroma 60 · L*(100−L*)/2500, at fixed lightness.
function labToRgb(L, a, b) {
  const fy = (L + 16) / 116, fx = fy + a / 500, fz = fy - b / 200;
  const finv = t => (t > 6 / 29 ? t * t * t : 3 * (6 / 29) * (6 / 29) * (t - 4 / 29));
  const X = 0.95047 * finv(fx), Y = finv(fy), Z = 1.08883 * finv(fz);
  const lin = [3.2406 * X - 1.5372 * Y - 0.4986 * Z, -0.9689 * X + 1.8758 * Y + 0.0415 * Z,
               0.0557 * X - 0.2040 * Y + 1.0570 * Z];
  return lin.map(c => {
    const v = c <= 0.0031308 ? 12.92 * c : 1.055 * Math.pow(Math.max(c, 0), 1 / 2.4) - 0.055;
    return Math.round(Math.min(1, Math.max(0, v)) * 255);
  });
}

const ROSE_SIZE = 96;   // displayed size (CSS px), see .legend canvas

function drawRose() {
  const cv = el('roseCanvas');
  if (!cv || drawRose.done) return;
  drawRose.done = true;
  const dpr = window.devicePixelRatio || 1, size = ROSE_SIZE, k = size / 132;
  cv.width = size * dpr; cv.height = size * dpr;
  const ctx = cv.getContext('2d');
  ctx.scale(dpr, dpr);
  const c = size / 2, rOut = 50 * k, rIn = 22 * k, L = 64;
  const chroma = 60 * Math.min(1, L * (100 - L) / 2500);
  const img = ctx.createImageData(size * dpr, size * dpr);
  for (let py = 0; py < size * dpr; py++) {
    for (let px = 0; px < size * dpr; px++) {
      const x = px / dpr - c, y = py / dpr - c, r = Math.hypot(x, y);
      if (r > rOut || r < rIn) continue;
      const compass = (Math.atan2(x, -y) * 180 / Math.PI + 360) % 360;   // 0 = N, clockwise
      const h = ((compass + 90) % 360) * Math.PI / 180;
      const [R, G, B] = labToRgb(L, chroma * Math.cos(h), chroma * Math.sin(h));
      const i = (py * size * dpr + px) * 4;
      img.data[i] = R; img.data[i + 1] = G; img.data[i + 2] = B; img.data[i + 3] = 255;
    }
  }
  ctx.putImageData(img, 0, 0);
  ctx.setTransform(dpr, 0, 0, dpr, 0, 0);
  ctx.textAlign = 'center'; ctx.textBaseline = 'middle';
  const text = cssVar('--text') || '#1d232b';
  const labels = [['N', 0], ['NE', 45], ['E', 90], ['SE', 135], ['S', 180], ['SW', 225], ['W', 270], ['NW', 315]];
  for (const [t, deg] of labels) {
    const a = deg * Math.PI / 180, rr = (t.length > 1 ? 36 : 58) * k;
    const x = c + rr * Math.sin(a), y = c - rr * Math.cos(a);
    // intercardinals on the coloured ring: dark; cardinals outside the ring: text colour
    ctx.fillStyle = t.length > 1 ? 'rgba(20,20,20,0.85)' : text;
    ctx.font = t.length > 1 ? '600 8px system-ui, sans-serif' : '700 10px system-ui, sans-serif';
    ctx.fillText(t, x, y);
  }
}

function updateRose() {
  // Visible whenever the relief is shown: alone, or on one side of the divider.
  const mode = STATE && effectiveMode();
  const reliefShown = mode === 'relief'
    || (mode === 'compare' && (STATE.compare.left === 'relief' || STATE.compare.right === 'relief'));
  const on = !!(STATE && STATE.main === 'relief_oriente' && reliefShown
               && LAYERS.get('relief_oriente'));
  el('legendBlock').hidden = !on;
  if (on) drawRose();
}

// --- external imagery background (JOSM, QGIS, iD…) ------------------------
function renderUseCard() {
  const origin = location.origin;
  const opts = META.layers.map(l =>
    '<option value="' + l.key + '">' + l.label + '</option>').join('');
  el('useBody').innerHTML =
    '<div class="row"><select id="useLayer" class="field">' + opts + '</select>' +
    '<button id="useCopy" class="btn btn-primary">Copy</button></div>' +
    '<div class="meta">XYZ URL (JOSM "TMS", QGIS "XYZ Tiles", uMap, MapLibre):</div>' +
    '<div class="mono" id="useUrl"></div>' +
    '<div class="meta">TileJSON: <a id="useJson" href="#"></a></div>' +
    '<div class="meta">WMTS: <a href="' + origin + '/tiles/wmts.xml">' + origin + '/tiles/wmts.xml</a></div>' +
    '<div class="meta">JOSM (all layers): <a href="' + origin + '/tiles/josm.imagery.xml">' + origin + '/tiles/josm.imagery.xml</a></div>' +
    '<div class="use-note">Max native zoom ' + META.max_native_zoom + '. ' + META.attribution_text + '</div>';
  const sel = el('useLayer');
  const refresh = () => {
    const key = sel.value;
    el('useUrl').textContent = origin + '/tiles/' + key + '/{z}/{x}/{y}.png';
    const a = el('useJson');
    a.textContent = origin + '/tiles/' + key + '.json';
    a.href = origin + '/tiles/' + key + '.json';
  };
  sel.addEventListener('change', refresh);
  el('useCopy').addEventListener('click', () => {
    const text = el('useUrl').textContent;
    if (navigator.clipboard && navigator.clipboard.writeText) {
      navigator.clipboard.writeText(text).then(() => toast('URL copied'),
                                               () => window.prompt('XYZ URL:', text));
    } else { window.prompt('XYZ URL:', text); }
  });
  refresh();
}

// --- tile generation (API /api/status, /api/preview, /api/generate) -------
// Ported from the former webapp: area drawing (＋), "complete everything"
// pass (⤒), cumulative selection (tile card button), run options, queue and
// tile-by-tile progress (frames on the map).
const GEN = { available: false, allowed: false, wasRunning: false, timer: null };
const genSel = new Set();          // "col,row" keys of the selected tiles
const genCorners = new Map();      // key → GPS corners [[lat, lon] × 4]
const genPolys = new Map();        // key → highlight polygon
const genFrames = new Map();       // name → coloured frame of a run tile
let genDrawing = false, genDrawStart = null, genDrawRect = null;
let genIgnoreClickUntil = 0;
let lastTileQuery = null;          // latlng of the last click (tile card)

for (const [pane, z] of [['genSel', 650], ['genFrames', 660], ['genDraw', 670], ['tileSel', 680]]) {
  map.createPane(pane).style.zIndex = String(z);
}

function genKey(c, r) { return c + ',' + r; }

function genApi(method, url, body) {
  return fetch(url, {
    method: method,
    headers: body ? { 'Content-Type': 'application/json' } : {},
    body: body ? JSON.stringify(body) : undefined,
  }).then(r => {
    if (!r.ok) {
      return r.json().catch(() => ({})).then(d => {
        throw new Error((d && d.detail) || ('HTTP ' + r.status));
      });
    }
    return r.json();
  });
}

function genOpenCard(msg) {
  if (msg !== undefined) el('genMsg').textContent = msg;
  // Tab already visible: no openTab, which would change the sheet height.
  if (panelVisibleTab() !== 'gen') openTab('gen');
}

function genFillViz() {
  el('genViz').innerHTML = META.layers.map(l =>
    '<option value="' + (l.step || l.key) + '">' + l.label + '</option>').join('');
}

function genSelectedViz() {
  return Array.from(el('genViz').selectedOptions).map(o => o.value);
}

function genRefreshSel() {
  for (const poly of genPolys.values()) poly.remove();
  genPolys.clear();
  for (const [key, corners] of genCorners.entries()) {
    if (!genSel.has(key) || !corners || corners.length < 4) continue;
    const poly = L.polygon(corners.map(c => [c[0], c[1]]), {
      pane: 'genSel', className: 'gen-sel', weight: 2, fillOpacity: 0.12,
    }).addTo(map);
    poly.on('click', (e) => {
      L.DomEvent.stopPropagation(e);
      genRemoveCell(key);
      toast('Tile removed from the selection');
    });
    genPolys.set(key, poly);
  }
  el('genGo').disabled = !genSel.size;
  if (genSel.size) {
    el('genMsg').textContent = genSel.size + (genSel.size > 1 ? ' tiles' : ' tile') + ' selected — ' +
      'click a highlight to remove a tile, set the options, then "Generate".';
  }
}

function genRemoveCell(key) {
  genSel.delete(key);
  genCorners.delete(key);
  genRefreshSel();
}

function genAddCells(cells) {
  let added = 0;
  for (const c of (cells || [])) {
    const k = genKey(c.col, c.row);
    if (!genSel.has(k)) { genSel.add(k); added++; }
    if (c.corners) genCorners.set(k, c.corners);
  }
  genRefreshSel();
  return added;
}

function genAddCellFromQuery() {
  if (!lastTileQuery) return;
  genApi('GET', 'api/cell?lat=' + lastTileQuery.lat + '&lng=' + lastTileQuery.lng)
    .then(d => {
      genAddCells([{ col: d.col, row: d.row, corners: d.corners }]);
      genOpenCard('1 tile selected — set the options, then "Generate".');
    })
    .catch(msg => toast('Failed: ' + msg.message, 6000));
}

function genSetDrawing(on) {
  genDrawing = on;
  document.body.classList.toggle('drawing', on);
  el('btnZone').classList.toggle('accent', on);
  if (on) map.dragging.disable(); else map.dragging.enable();
  if (!on && genDrawRect) { genDrawRect.remove(); genDrawRect = null; }
  genDrawStart = null;
  if (on) genOpenCard('Draw a rectangle on the map (click ＋ again to cancel).');
}

map.on('mousedown', (e) => {
  if (!genDrawing) return;
  genDrawStart = e.latlng;
  if (genDrawRect) genDrawRect.remove();
  genDrawRect = L.rectangle([genDrawStart, genDrawStart], {
    pane: 'genDraw', color: cssVar('--gen-pending'), weight: 2, dashArray: '6 4',
    fillOpacity: 0.05, interactive: false,
  }).addTo(map);
});
map.on('mousemove', (e) => {
  if (!genDrawing || !genDrawStart || !genDrawRect) return;
  genDrawRect.setBounds(L.latLngBounds(genDrawStart, e.latlng));
});
map.on('mouseup', (e) => {
  if (!genDrawing || !genDrawStart) return;
  const b = L.latLngBounds(genDrawStart, e.latlng);
  genDrawStart = null;
  genIgnoreClickUntil = Date.now() + 400;  // no tile selection right after drawing
  if (Math.abs(b.getWest() - b.getEast()) < 1e-9 ||
      Math.abs(b.getNorth() - b.getSouth()) < 1e-9) return;
  genSetDrawing(false);
  if (genDrawRect) { genDrawRect.remove(); genDrawRect = null; }
  genOpenCard('Analysing the area…');
  genApi('POST', 'api/preview', {
    bbox: [b.getWest(), b.getSouth(), b.getEast(), b.getNorth()],
    regenerate: el('genRegen').checked,
    viz: genSelectedViz(),
  }).then(d => {
    const added = genAddCells(d.cells);
    genOpenCard((added ? added + (added > 1 ? ' new tiles' : ' new tile') + ' selected'
                       : 'area already covered — tick "Regenerate" to force') +
      (d.capped ? ' — area capped, draw a smaller rectangle' : '') + '.');
  }).catch(msg => genOpenCard('Error: ' + msg.message));
});

function genComplete() {
  genOpenCard('Analysing the already-downloaded tiles…');
  genApi('POST', 'api/preview', {
    all_missing: true,
    regenerate: el('genRegen').checked,
    viz: genSelectedViz(),
  }).then(d => {
    const added = genAddCells(d.cells);
    const n = added || d.count || 0;
    genOpenCard(n + (n === 1 ? ' tile' : ' tiles') + ' to complete' +
      (d.capped ? ' — capped at 10,000 per run' : '') + '.');
    if (genPolys.size) {
      const bounds = L.latLngBounds([]);
      genPolys.forEach(p => bounds.extend(p.getBounds()));
      map.fitBounds(bounds, { padding: [40, 40] });
    }
  }).catch(msg => genOpenCard('Error: ' + msg.message));
}

function genLaunch() {
  const tiles = [...genSel].map(k => k.split(',').map(Number));
  if (!tiles.length) return;
  genApi('POST', 'api/generate', {
    tiles: tiles,
    regenerate: el('genRegen').checked,
    viz: genSelectedViz(),
  }).then(d => {
    genSel.clear();
    genCorners.clear();
    genRefreshSel();
    GEN.wasRunning = true;
    genPollNow();
    toast(d.demarré ? ('Generation started: ' + d.tuiles + ' tile(s)')
         : ('Queued (' + d.en_file + '): ' + d.tuiles + ' tile(s)'));
  }).catch(msg => toast('Failed: ' + msg.message, 6000));
}

// Frames of the run's tiles (pulsing orange = rendering, blue = pending,
// red = failed) — full redraw on every poll, it is cheap.
function genDrawFrames(tiles) {
  for (const poly of genFrames.values()) poly.remove();
  genFrames.clear();
  for (const t of (tiles || [])) {
    if (t.state === 'done' || !t.corners || t.corners.length < 4) continue;
    const cls = t.state === 'running' ? 'gen-frame-running'
              : t.state === 'failed' ? 'gen-frame-failed' : 'gen-frame-pending';
    const poly = L.polygon(t.corners.map(c => [c[0], c[1]]), {
      pane: 'genFrames', className: cls, weight: 2, fillOpacity: 0.15,
      interactive: false,
    }).addTo(map);
    genFrames.set(t.name || JSON.stringify(t.corners[0]), poly);
  }
}

// End of run: the map refreshes (new layers/tiles, fresh tile stamp) and the
// pyramid maintenance is restarted server-side.
function genAfterRun() {
  fetch('api/map/meta').then(r => r.json()).then(meta => {
    META = meta;
    buildLayers();
    renderPanel();
    renderBaseRow();
    applyLayers();
    renderUseCard();
  }).catch(() => {});
  fetch('api/map/background', { method: 'POST' }).catch(() => {});
  // Tile card left selected during the run: stale (resolution, generation
  // date, layers…) — reload it without ever deselecting.
  if (SELECTED_TILE && lastTileQuery) {
    fetch('api/map/tile?lat=' + lastTileQuery.lat + '&lng=' + lastTileQuery.lng)
      .then(r => r.ok ? r.json() : null)
      .catch(() => null)
      .then(d => { if (d) selectTile(d, lastTileQuery); });
  }
}

function genUpdateStatus(d) {
  const queued = (d.queue || []).length;
  if (d.running || queued) {
    el('genActions').hidden = true;
    el('genOpts').hidden = true;
    el('genRun').hidden = false;
    const tiles = d.tiles || [];
    const done = tiles.filter(t => t.state === 'done').length;
    const failed = tiles.filter(t => t.state === 'failed').length;
    let txt = d.running ? ('Run in progress — ' + done + '/' + tiles.length + ' tile(s)')
                        : 'Starting the next run…';
    if (failed) txt += ' • ' + failed + ' failed';
    if (queued) txt += ' • ' + queued + ' queued request(s)';
    el('genProgress').textContent = txt;
    el('genLog').textContent = (d.log || []).slice(-12).join('\n');
    genDrawFrames(tiles);
    GEN.wasRunning = true;
  } else {
    el('genRun').hidden = true;
    el('genActions').hidden = !GEN.available;
    el('genOpts').hidden = false;
    genDrawFrames(null);
    if (GEN.wasRunning) {
      GEN.wasRunning = false;
      toast(d.returncode === 0 ? 'Generation finished'
           : 'Generation interrupted (code ' + d.returncode + ')', 6000);
      genAfterRun();
    }
  }
  el('genBadge').textContent = d.running ? '● running'
                          : queued ? ('⏱ ' + queued) : '';
  el('btnZone').classList.toggle('busy', !!d.running || !!queued);
}

function genPollNow() {
  if (!GEN.available) return;
  fetch('api/status').then(r => r.ok ? r.json() : null).then(d => {
    if (d) genUpdateStatus(d);
    genPollSoon();
  }).catch(() => genPollSoon());
}

function genPollSoon() {
  clearTimeout(GEN.timer);
  GEN.timer = setTimeout(genPollNow, GEN.wasRunning ? 3000 : 20000);
}

el('btnZone').addEventListener('click', () => genSetDrawing(!genDrawing));
el('btnComplete').addEventListener('click', genComplete);
el('genClear').addEventListener('click', () => {
  genSel.clear();
  genCorners.clear();
  genRefreshSel();
  genOpenCard('Selection cleared. Draw an area (＋) or complete (⤒).');
});
el('genGo').addEventListener('click', genLaunch);
el('genStop').addEventListener('click', () =>
  genApi('POST', 'api/stop')
    .then(() => toast('Stop requested'))
    .catch(msg => toast('Failed: ' + msg.message, 6000)));
el('genQueueClear').addEventListener('click', () =>
  genApi('POST', 'api/queue/clear')
    .then(d => toast((d.retirées || 0) + ' request(s) removed'))
    .catch(msg => toast('Failed: ' + msg.message, 6000)));

// --- PDF export (printed field sheet) ---
// Frame = printed area, anchored on the ground (centre PRINT.center): the map
// moves freely around it; drag it with the mouse or a finger.
// Exact geometry computed by the server (Lambert 93 projection).
const PRINT_LS = 'lidar-print';
const PRINT = { on: false, rect: null, handle: null, seq: 0, center: null, corners: null, drag: null,
                dragging: false };
map.createPane('printFrame').style.zIndex = '690';

function printSettings() {
  return { paper: el('printPaper').value, orient: el('printOrient').value,
           scale: el('printScale').value, title: el('printTitle').value.trim() };
}

function printQuery(s, withTitle) {
  const c = PRINT.center || map.getCenter();
  const q = new URLSearchParams({ lat: c.lat.toFixed(6), lon: c.lng.toFixed(6),
                                  paper: s.paper, orient: s.orient, scale: s.scale });
  if (withTitle && s.title) q.set('title', s.title);
  return q.toString();
}

function printSave() {
  const s = printSettings();
  if (PRINT.center) s.center = [PRINT.center.lat, PRINT.center.lng];
  lsSet(PRINT_LS, s);
}

function printLoad() {
  const raw = lsGet(PRINT_LS, {});
  // Corrupted value (key shared with another app, quota exceeded while
  // writing…): a malformed object is ignored rather than crashing.
  const s = raw && typeof raw === 'object' && !Array.isArray(raw) ? raw : {};
  for (const [k, id] of [['paper', 'printPaper'], ['orient', 'printOrient'],
                         ['scale', 'printScale'], ['title', 'printTitle']]) {
    if (typeof s[k] === 'string') el(id).value = s[k];
  }
  if (Array.isArray(s.center) && s.center.length === 2 &&
      s.center.every((n) => typeof n === 'number' && Number.isFinite(n))) {
    PRINT.center = L.latLng(s.center);
  }
}

// Fits the view to the frame while leaving room for the panel (left column
// on desktop, bottom sheet on phone): otherwise the frame goes under it.
function printFit() {
  if (!PRINT.corners) return;
  const r = el('panel').getBoundingClientRect();
  const panelWidth = isPhone() ? 0 : r.right;
  const sheetHeight = isPhone() ? r.height : 0;
  map.fitBounds(L.latLngBounds(PRINT.corners),
                { paddingTopLeft: [panelWidth + 30, 60], paddingBottomRight: [70, sheetHeight + 20] });
}

function printDraw(corners) {
  PRINT.corners = corners;
  if (PRINT.rect) PRINT.rect.setLatLngs(corners);
  else PRINT.rect = L.polygon(corners, { pane: 'printFrame', color: cssVar('--print'), weight: 2,
                                         dashArray: '8 5', fill: false, interactive: false }).addTo(map);
  if (PRINT.handle) { PRINT.handle.setLatLng(PRINT.center); return; }
  PRINT.handle = L.marker(PRINT.center, {
    pane: 'printFrame', draggable: true, autoPan: true, keyboard: false,
    title: 'Drag to move the printed area',
    icon: L.divIcon({ className: 'print-handle', html: '✥', iconSize: [34, 34] }),
  }).addTo(map);
  PRINT.handle.on('dragstart', printDragStart);
  PRINT.handle.on('drag', printDragMove);
  PRINT.handle.on('dragend', printDragEnd);
}

// fit: fit the view to the frame once the geometry is received.
function printRefreshFrame(fit) {
  if (!PRINT.on) return;
  const seq = ++PRINT.seq;
  fetch('api/export/frame?' + printQuery(printSettings(), false))
    .then(r => r.ok ? r.json() : Promise.reject(new Error('HTTP ' + r.status)))
    .then(d => {
      if (seq !== PRINT.seq || !PRINT.on || PRINT.drag) return;
      printDraw(d.corners);
      el('printInfo').textContent = d.width_m + ' × ' + d.height_m + ' m';
      if (fit === true) printFit();
    })
    .catch(() => { if (seq === PRINT.seq) el('printInfo').textContent = ''; });
}

// Dragging the handle: the frame follows live (translation in layer pixels,
// stable during auto-panning); exact geometry requested again from the
// server on release.
function printDragStart() {
  PRINT.dragging = true;
  PRINT.drag = { start: map.latLngToLayerPoint(PRINT.handle.getLatLng()),
                 corners: PRINT.corners.map(c => map.latLngToLayerPoint(c)) };
}

function printDragMove() {
  const d = PRINT.drag;
  if (!d) return;
  const delta = map.latLngToLayerPoint(PRINT.handle.getLatLng()).subtract(d.start);
  PRINT.rect.setLatLngs(d.corners.map(p => map.layerPointToLatLng(p.add(delta))));
}

function printDragEnd() {
  PRINT.drag = null;
  PRINT.center = PRINT.handle.getLatLng();
  PRINT.corners = PRINT.rect.getLatLngs()[0];
  printSave();
  printRefreshFrame();
  setTimeout(() => { PRINT.dragging = false; }, 300);
}

function printCenterHere() {
  PRINT.center = map.getCenter();
  printSave();
  printRefreshFrame();
}

// Frame shown while the PDF export tab is visible (panel:tab event, fired on
// every panel render: nothing happens if the state is unchanged).
// explicit: false only for the startup render (BOOTSTRAPPING: a remembered
// Export tab restored over a shared link or the initial URL), true for every
// later render (tab click, keyboard shortcut, sheet reopened…). When false,
// neither is the view fitted to the frame, nor is the frame itself recentred
// on the view (otherwise a frame placed elsewhere on the ground jumps to the
// centre of the screen, or a shared link's zoom is overwritten — see
// printRefreshFrame(fit)).
function printSetOpen(on, explicit) {
  if (PRINT.on === on) return;
  PRINT.on = on;
  if (on) {
    // Frame recentred on the view only if it is out of view AND the opening
    // is explicit; otherwise kept where it was (or placed at the centre if it
    // never existed — first visit without a saved lidar-print).
    if (!PRINT.center) PRINT.center = map.getCenter();
    else if (explicit && !map.getBounds().contains(PRINT.center)) PRINT.center = map.getCenter();
    printRefreshFrame(!!explicit);
  } else {
    if (PRINT.rect) PRINT.rect.remove();
    if (PRINT.handle) PRINT.handle.remove();
    PRINT.rect = PRINT.handle = PRINT.corners = null;
  }
}

function printExport() {
  const btn = el('printGo');
  btn.disabled = true;
  el('printMsg').textContent = 'Generating the PDF…';
  fetch('api/export/pdf?' + printQuery(printSettings(), true))
    .then(r => {
      if (!r.ok) {
        return r.json().catch(() => ({})).then(d => {
          throw new Error((d && d.detail) || ('HTTP ' + r.status));
        });
      }
      const m = /filename="([^"]+)"/.exec(r.headers.get('Content-Disposition') || '');
      return r.blob().then(b => ({ b: b, name: m ? m[1] : 'relief.pdf' }));
    })
    .then(({ b, name }) => {
      const a = document.createElement('a');
      a.href = URL.createObjectURL(b);
      a.download = name;
      document.body.appendChild(a);
      a.click();
      a.remove();
      setTimeout(() => URL.revokeObjectURL(a.href), 10000);
      el('printMsg').textContent = 'Downloaded: ' + name;
    })
    .catch(e => { el('printMsg').textContent = 'Failed: ' + e.message; })
    .finally(() => { btn.disabled = false; });
}

el('printGo').addEventListener('click', printExport);
el('printHere').addEventListener('click', printCenterHere);
el('printFit').addEventListener('click', printFit);
for (const id of ['printPaper', 'printOrient', 'printScale']) {
  el(id).addEventListener('change', () => { printSave(); printRefreshFrame(true); });
}
el('printTitle').addEventListener('change', printSave);
printLoad();

document.addEventListener('panel:tab', (e) => {
  printSetOpen(e.detail.visible === 'print', !BOOTSTRAPPING);
  if (e.detail.visible !== 'gen' && genDrawing) genSetDrawing(false);
});

// --- tabbed panel -------------------------------------------------------------
const PANEL_LS = 'lidar-panel';
// Keeps only known keys of the right type and (for sheet) within the valid
// list: a corrupted value would otherwise break the CSS (panel.dataset.sheet
// unknown to map.css) or the displayed tab.
function _sanitizedPanelLS() {
  const raw = lsGet(PANEL_LS, {});
  const s = raw && typeof raw === 'object' && !Array.isArray(raw) ? raw : {};
  const out = {};
  if (typeof s.tab === 'string') out.tab = s.tab;
  if (typeof s.collapsed === 'boolean') out.collapsed = s.collapsed;
  if (['closed', 'half', 'full'].includes(s.sheet)) out.sheet = s.sheet;
  if (typeof s.reading === 'boolean') out.reading = s.reading;
  return out;
}
const PANEL = Object.assign({ tab: 'view', collapsed: false, sheet: 'half', reading: false }, _sanitizedPanelLS());
// want = chosen (remembered) tab; tab = displayed tab. Generation still
// unknown at startup (api/status): Display meanwhile, then the chosen tab
// comes back as soon as it is offered.
PANEL.want = PANEL.tab;
const phoneQuery = window.matchMedia('(max-width: 720px)');
const isPhone = () => phoneQuery.matches;

// Offered tabs: Generation only if the generator answers and this browser
// is allowed to launch runs (same rule as the former buttons).
function panelTabs() {
  return ['view', 'tile', 'print', 'gen', 'share'].filter(t => t !== 'gen' || (GEN.available && GEN.allowed));
}

// Tab actually visible, or null (panel collapsed or sheet closed — in which
// case NO tab is on screen, not even the remembered one: panel:tab must
// close the export frame if it was open, whatever triggered this panel
// render — grip dragged/tapped, resize, phoneQuery change, openTab's
// setTimeout(panelRender, 220)…).
function panelVisibleTab() {
  if (isPhone() ? PANEL.sheet === 'closed' : PANEL.collapsed) return null;
  return PANEL.tab;
}

function panelSave() { lsSet(PANEL_LS, { tab: PANEL.want, collapsed: PANEL.collapsed, sheet: PANEL.sheet, reading: PANEL.reading }); }

function panelRender() {
  const tabs = panelTabs();
  PANEL.tab = tabs.includes(PANEL.want) ? PANEL.want : 'view';
  el('panelTabs').querySelectorAll('button[data-tab]').forEach(b => {
    b.hidden = !tabs.includes(b.dataset.tab);
    b.setAttribute('aria-selected', String(b.dataset.tab === PANEL.tab));
  });
  for (const t of ['view', 'tile', 'print', 'gen', 'share']) el('tab-' + t).hidden = t !== PANEL.tab;
  const panel = el('panel');
  // Collapse into an icon strip: desktop only (the phone has its sheet).
  const collapsed = PANEL.collapsed && !isPhone();
  panel.classList.toggle('collapsed', collapsed);
  panel.dataset.sheet = PANEL.sheet;
  document.body.classList.toggle('panel-collapsed', collapsed);
  // Height covered by the sheet, which the scale, attribution and messages
  // stay clear of; full sheet: the map is hidden, nothing to clear (otherwise
  // they would climb to the top of the screen, over the tools).
  const sheetPx = isPhone() && PANEL.sheet !== 'full' ? panel.getBoundingClientRect().height : 0;
  document.body.style.setProperty('--sheet-h', sheetPx + 'px');
  document.dispatchEvent(new CustomEvent('panel:tab', { detail: { tab: PANEL.tab, visible: panelVisibleTab() } }));
}

function openTab(tab) {
  if (!panelTabs().includes(tab)) return;
  const before = PANEL.sheet;
  // Active tab tapped again on phone: the sheet changes height.
  if (isPhone() && tab === PANEL.tab && PANEL.sheet !== 'closed') {
    PANEL.sheet = PANEL.sheet === 'half' ? 'full' : 'half';
  } else if (isPhone() && PANEL.sheet === 'closed') {
    PANEL.sheet = 'half';
  }
  const resized = isPhone() && PANEL.sheet !== before;
  PANEL.want = PANEL.tab = tab;
  PANEL.collapsed = false;
  panelSave(); panelRender();
  if (resized) setTimeout(panelRender, 220);   // final height after the CSS transition
}

function setCollapsed(on) { PANEL.collapsed = !!on; panelSave(); panelRender(); map.invalidateSize(); }

function setSheet(state) {
  if (!['closed', 'half', 'full'].includes(state)) return;
  PANEL.sheet = state; panelSave();
  panelRender();
  setTimeout(panelRender, 220);   // final height after the CSS transition
}

el('panelTabs').querySelectorAll('button[data-tab]').forEach(b =>
  b.addEventListener('click', () => openTab(b.dataset.tab)));
el('panelCollapse').addEventListener('click', () => setCollapsed(!PANEL.collapsed));
// Open/closed state of "How to read" remembered separately (independent of
// the active tab).
el('readingBlock').open = !!PANEL.reading;
el('readingBlock').addEventListener('toggle', () => {
  PANEL.reading = el('readingBlock').open;
  panelSave();
});
phoneQuery.addEventListener('change', panelRender);
window.addEventListener('resize', panelRender);   // sheet height in vh (rotation)

// Sheet grip: drag up / down, release onto the nearest height; a simple tap
// moves it up one step (full goes back to half).
(function sheetDrag() {
  const grip = el('sheetGrip');
  let start = null;
  grip.addEventListener('pointerdown', (e) => {
    start = { y: e.clientY, h: el('panel').getBoundingClientRect().height };
    grip.setPointerCapture(e.pointerId);
    el('panel').style.transition = 'none';
  });
  grip.addEventListener('pointermove', (e) => {
    if (!start) return;
    const h = Math.max(72, Math.min(window.innerHeight - 16, start.h + start.y - e.clientY));
    el('panel').style.height = h + 'px';
  });
  const end = (e) => {
    if (!start) return;
    const moved = Math.abs(e.clientY - start.y) > 6;
    const h = el('panel').getBoundingClientRect().height;
    el('panel').style.height = ''; el('panel').style.transition = '';
    start = null;
    if (!moved) { setSheet(PANEL.sheet === 'closed' ? 'half' : PANEL.sheet === 'half' ? 'full' : 'half'); return; }
    const stops = { closed: 72, half: window.innerHeight * 0.45, full: window.innerHeight - 16 };
    const best = Object.entries(stops).sort((a, b) => Math.abs(a[1] - h) - Math.abs(b[1] - h))[0][0];
    setSheet(best);
  };
  grip.addEventListener('pointerup', end);
  grip.addEventListener('pointercancel', end);
})();

// --- startup --------------------------------------------------------------
function fitData() {
  if (META.bounds) {
    map.fitBounds([[META.bounds[1], META.bounds[0]], [META.bounds[3], META.bounds[2]]],
                  { padding: [30, 30] });
  } else {
    map.setView([46.6, 2.5], 6);
  }
}

fetch('api/map/meta').then(r => r.json()).then(meta => {
  META = meta;
  if (!META.layers.length) {
    toast('No visualisation available in the cache.', 10000);
  }
  STATE = loadState(META);
  // The chosen state (server defaults, then shared link) is persisted right
  // away: what is on screen is what will be reloaded.
  saveState();
  const hash = parseHash();
  if (hash) map.setView([hash.lat, hash.lng], hash.zoom);
  else fitData();
  buildLayers();
  renderPanel();
  renderBaseRow();
  panelRender();
  BOOTSTRAPPING = false;
  renderUseCard();
  genFillViz();
  // Generation rights: the Generation tab is shown if the server can generate
  // (local pipeline or LIDAR_GENERATION_URL) AND the browser comes from the
  // allowed network (LIDAR_REGEN_CIDR) — otherwise silently hidden.
  fetch('api/status').then(r => r.ok ? r.json() : null).then(d => {
    if (!d) return;
    GEN.available = !!d.available;
    GEN.allowed = d.regen_allowed !== false;
    const show = GEN.available && GEN.allowed;
    panelRender();
    // The tile card may have shown before /api/status answered ("Regenerate"
    // button missing, GEN still unknown): render it again.
    if (SELECTED_TILE) renderTabTile();
    if (show) { genUpdateStatus(d); genPollNow(); }
  }).catch(() => {});
}).catch(() => {
  toast('Tile server unreachable.', 10000);
  panelRender();
  // This render also counts as the first one (initial load failed): without
  // this reset, a remembered Export tab would NEVER reframe the view again,
  // even after a later explicit opening.
  BOOTSTRAPPING = false;
});

let applyingHash = false;
window.addEventListener('hashchange', () => {
  // Shared link pasted into the current browser tab: the view (and the layer
  // state, if present) is applied without reloading.
  if (applyingHash || !META) return;
  const h = parseHash();
  if (!h) return;
  applyingHash = true;
  map.setView([h.lat, h.lng], h.zoom);
  if (h.main || h.view || h.base || h.compare || h.intensity != null) {
    STATE = loadState(META);
    saveState(); renderPanel(); renderBaseRow(); applyLayers();
  }
  setTimeout(() => { applyingHash = false; }, 0);
});

map.on('moveend zoomend', saveHashSoon);
// Sequence token: a response arriving after a more recent click (double
// click, slow request) must never overwrite the selection state.
let tileClickSeq = 0;
map.on('click', (e) => {
  // No selection while drawing an area nor right after releasing the export
  // frame handle. A double click (Leaflet zoom) arrives here as two single
  // clicks: the second (detail > 1) must not toggle back the selection the
  // first one just made.
  if (genDrawing || Date.now() < genIgnoreClickUntil || PRINT.dragging) return;
  if (e.originalEvent && e.originalEvent.detail > 1) return;
  const seq = ++tileClickSeq;
  fetch('api/map/tile?lat=' + e.latlng.lat + '&lng=' + e.latlng.lng)
    .then(r => r.ok ? r.json() : null)
    .catch(() => null)
    .then(d => {
      if (seq !== tileClickSeq) return;   // a more recent click already handled
      if (!d) { toast('Server unreachable: try again in a moment.', 5000); return; }
      // Click on the already-selected tile: deselect. Otherwise the selection
      // moves, without changing the displayed tab.
      if (SELECTED_TILE && SELECTED_TILE.col === d.col && SELECTED_TILE.row === d.row) {
        clearTileSelection();
      } else {
        selectTile(d, e.latlng);
      }
    });
});

el('btnShare').addEventListener('click', () => {
  const url = location.origin + location.pathname + viewHash(true);
  history.replaceState(null, '', url);
  if (navigator.clipboard && navigator.clipboard.writeText) {
    navigator.clipboard.writeText(url).then(() => toast('Link copied'),
                                            () => window.prompt('Link:', url));
  } else { window.prompt('Link:', url); }
});
el('btnDefault').addEventListener('click', () => {
  const body = {
    main: STATE.main,
    mode: STATE.mode,
    base: STATE.base,
  };
  fetch('api/map/defaults', {
    method: 'POST', headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify(body),
  }).then(r => r.ok ? r.json() : Promise.reject('HTTP ' + r.status))
    .then(() => {
      META.default_main = STATE.main; META.default_mode = STATE.mode;
      META.default_base = STATE.base;
      toast('Display saved as the default');
    })
    .catch(msg => toast('Saving failed: ' + msg, 6000));
});

el('modeSeg').querySelectorAll('button').forEach(b =>
  b.addEventListener('click', () => setMode(b.dataset.mode)));
el('reliefIntensity').addEventListener('input', (e) => {
  STATE.intensity = clampIntensity(e.target.value);
  el('reliefIntensityVal').textContent = fmtIntensity(STATE.intensity);
  applyLayers();
});
el('reliefIntensity').addEventListener('change', saveState);
el('mainSel').addEventListener('change', (e) => {
  STATE.main = e.target.value;
  saveState(); renderPanel(); applyLayers();
});
for (const [id, side] of [['compareLeft', 'left'], ['compareRight', 'right']]) {
  el(id).addEventListener('change', (e) => {
    STATE.compare[side] = validSide(e.target.value) || STATE.compare[side];
    saveState(); renderPanel(); applyLayers();
  });
}

el('btnReset').addEventListener('click', () => {
  // Forgets the local state and takes the configuration served by the server.
  lsDel(LS_KEY);
  fetch('api/map/meta').then(r => r.json()).then(meta => {
    META = meta;
    STATE = defaultState(META);
    saveState(); renderPanel(); renderBaseRow(); applyLayers();
    toast('Default configuration restored');
  }).catch(() => toast('Server unreachable', 6000));
});

el('baseToggle').addEventListener('click', () => {
  STATE.base.on = !STATE.base.on;
  saveState(); renderBaseRow(); applyLayers();
});
el('baseName').addEventListener('click', () => {
  STATE.base.dark = !(STATE.base.dark ?? themeIsDark());
  saveState(); applyLayers();
});
el('baseOpacity').addEventListener('input', (e) => {
  STATE.base.opacity = Number(e.target.value) / 100;
  el('basePct').textContent = e.target.value + '%';
  base.setOpacity(STATE.base.opacity);
});
el('baseOpacity').addEventListener('change', saveState);
el('btnTheme').addEventListener('click', () => {
  THEME = applyTheme(THEME_NEXT[THEME]);
  lsSet(THEME_LS, THEME);
});
if (darkQuery && darkQuery.addEventListener) {
  darkQuery.addEventListener('change', () => {
    if (THEME !== 'auto') return;
    if (STATE) applyLayers();
    redrawRose();
  });
}
el('zoomIn').addEventListener('click', () => map.zoomIn(1));
el('zoomOut').addEventListener('click', () => map.zoomOut(1));
el('zoomFit').addEventListener('click', fitData);
el('gps').addEventListener('click', () => {
  if (!('geolocation' in navigator)) {
    toast('Geolocation unavailable (HTTPS required).', 6000);
    return;
  }
  const btn = el('gps');
  btn.classList.add('busy');
  navigator.geolocation.getCurrentPosition((pos) => {
    btn.classList.remove('busy');
    const ll = [pos.coords.latitude, pos.coords.longitude];
    map.setView(ll, Math.max(map.getZoom(), 16));
    if (window._gpsMarker) window._gpsMarker.remove();
    window._gpsMarker = L.circleMarker(ll, {
      radius: 6, color: cssVar('--gps'), fillColor: cssVar('--gps'), fillOpacity: 0.9
    }).addTo(map);
  }, (err) => {
    btn.classList.remove('busy');
    const why = err && err.code === 1 ? 'Permission denied'
      : err && err.code === 3 ? 'Timed out' : 'Position unavailable';
    toast(why + ' (geolocation requires HTTPS).', 6000);
  }, { enableHighAccuracy: true, timeout: 15000, maximumAge: 60000 });
});
document.addEventListener('keydown', (e) => {
  const typing = e.target && e.target.closest && e.target.closest('input, select, textarea');
  if (typing || e.ctrlKey || e.metaKey || e.altKey) {
    if (e.key === 'Escape' && typing) e.target.blur();
    return;
  }
  // P: relief → precision → compare → relief
  if ((e.key === 'p' || e.key === 'P') && META && STATE && precisionKey()) {
    const i = VIEW_KEYS.indexOf(STATE.mode);
    setMode(VIEW_KEYS[(i + 1) % VIEW_KEYS.length], true);
    return;
  }
  // 1–5: panel tabs (Generation skipped when hidden)
  if (/^[1-5]$/.test(e.key)) {
    const tab = ['view', 'tile', 'print', 'gen', 'share'][Number(e.key) - 1];
    if (panelTabs().includes(tab)) openTab(tab);
    return;
  }
  if (e.key === 'Escape') {
    if (genDrawing) { genSetDrawing(false); return; }
    if (SELECTED_TILE) { clearTileSelection(); return; }
    if (isPhone()) setSheet('closed'); else setCollapsed(true);
  }
});