// dock.js — asset dock (left) + inspector (right). Talks to Stage's public API only.
// M1: click a card to add; click an animation to bake onto the selected character; drop local
// files onto the view for offline/upload work. M2: Lane B takes over clip placement.
import { stats } from './room3d.js';

const TABS = ['characters', 'props', 'backdrops', 'animations'];

export class Dock {
  constructor({ stage, dockEl, inspectorEl, viewEl }){
    this.stage = stage; this.dock = dockEl; this.insp = inspectorEl; this.view = viewEl;
    this.tree = { characters:[], props:[], backdrops:[], animations:[] };
    this.tab = 'characters';
    stage.onSelect(en => this.renderInspector(en));
    stage.onChange(en => { if(en && en.id === this._selId) this.renderInspector(en); });
    this._selId = null;
    this._buildTabs();
    this._viewDrop();
    this._dropZone();
    this.load();
  }

  async load(){
    try {
      const r = await fetch('/assets/tree');
      if(!r.ok) throw new Error(r.status);
      this.tree = { characters:[], props:[], backdrops:[], animations:[], ...(await r.json()) };
    } catch(e){
      this._offline = true;
      this.tree = { characters:[], props:[], backdrops:[], animations:[] };
    }
    this.renderBrowser();
  }

  _buildTabs(){
    const add = document.createElement('div'); add.className = 'addbar';
    for(const [txt, what] of [['+ camera','camera'], ['+ key light','keylight'], ['+ ambient','ambient']]){
      const b = document.createElement('button'); b.textContent = txt;
      b.onclick = () => this._addRig(what).catch(e => this._toast('failed: ' + String(e).slice(0,80)));
      add.appendChild(b);
    }
    this.dock.appendChild(add);

    const bar = document.createElement('div'); bar.className = 'tabs';
    for(const t of TABS){
      const b = document.createElement('button'); b.textContent = t.toUpperCase();
      b.className = t === this.tab ? 'on' : '';
      b.onclick = () => { this.tab = t; [...bar.children].forEach(c => c.classList.toggle('on', c === b)); this.renderBrowser(); };
      bar.appendChild(b);
    }
    this.dock.appendChild(bar);
    this.list = document.createElement('div'); this.list.className = 'cards';
    this.dock.appendChild(this.list);
  }

  // drag a dock card onto the viewport → place at the drop point (chars/props) or bake onto the
  // character under the cursor (animations). Library items only; local files use the window drop.
  _viewDrop(){
    this.view.addEventListener('dragover', e => {
      if([...e.dataTransfer.types].includes('application/scenegod')) e.preventDefault(); });
    this.view.addEventListener('drop', async e => {
      const raw = e.dataTransfer.getData('application/scenegod');
      if(!raw) return;                         // a local file drop — let the window handler take it
      e.preventDefault(); e.stopPropagation();
      const { tab, path, name } = JSON.parse(raw);
      try {
        if(tab === 'animations'){
          const id = this.stage.entityAt(e.clientX, e.clientY, 'character');
          if(!id) return this._toast('drop the clip onto a character');
          return this._applyClip(id, path, 0);
        }
        const kind = tab === 'characters' ? 'character' : tab === 'props' ? 'prop' : 'backdrop';
        const desc = { kind, label: name, source:{ type:'assets', path } };
        if(kind === 'backdrop') desc.params = { mode:'plane', image:path, width:10 };
        else desc.transform = { pos: this.stage.screenToFloor(e.clientX, e.clientY), rot:[0,0,0], scale:1 };
        const en = await this.stage.addEntity(desc);
        this.stage.select(en.id);
      } catch(err){ this._toast('drop failed: ' + String(err).slice(0,90)); }
    });
  }

  // /assets/tree item shape (confirmed by Lane C): {name, path, formats:[...], thumb: relpath|null}
  _path(it){ return it.path; }
  _name(it){ return it.name || (it.path || '').split('/').pop(); }

  renderBrowser(){
    this.list.innerHTML = '';
    const items = this.tree[this.tab] || [];
    if(!items.length){
      this.list.innerHTML = `<div class="empty">${this._offline
        ? 'server offline — drag a .glb / .fbx / image onto the view'
        : 'nothing here — drop banks into assets/' + this.tab + '/'}</div>`;
      return;
    }
    const icon = { characters:'🕺', props:'🪑', backdrops:'🖼', animations:'🏃' }[this.tab];
    for(const it of items){
      const c = document.createElement('div'); c.className = 'card'; c.draggable = true;
      const th = it.thumb
        ? `<img class="th" loading="lazy" src="/assets/file?path=${encodeURIComponent(it.thumb)}">`
        : `<div class="th">${icon}</div>`;
      c.innerHTML = `${th}<div class="nm">${this._name(it)}</div>`;
      c.onclick = () => this._addFromLibrary(it);
      c.ondragstart = ev => ev.dataTransfer.setData('application/scenegod',
        JSON.stringify({ tab: this.tab, path: this._path(it), name: this._name(it) }));
      this.list.appendChild(c);
    }
  }

  async _addFromLibrary(it){
    const path = this._path(it);
    try {
      if(this.tab === 'animations'){
        const en = this.stage.getEntity(this._selId);
        if(!en || en.kind !== 'character') return this._toast('select a character first');
        return this._applyClip(en.id, path, 0);
      }
      const kind = this.tab === 'characters' ? 'character' : this.tab === 'props' ? 'prop' : 'backdrop';
      const desc = { kind, label: this._name(it), source: { type:'assets', path } };
      if(kind === 'backdrop') desc.params = { mode:'plane', image:path, width:10 };
      this._toast('loading ' + this._name(it) + '…');
      const en = await this.stage.addEntity(desc);
      this.stage.select(en.id);
      this._toast('');
    } catch(e){ this._toast('failed: ' + String(e).slice(0, 100)); }
  }

  // clips go to the timeline once it's mounted; standalone preview only when it isn't
  async _applyClip(id, path, clipIndex){
    if(window.timeline){
      dispatchEvent(new CustomEvent('scenegod:clipdrop', { detail:{ id, path, clipIndex } }));
      this._toast('+ ' + path.split('/').pop() + ' → timeline');
      return;
    }
    this._toast('baking clip…');
    const clip = await this.stage.prepareClip(id, path, clipIndex);
    this.stage.playClip(id, clip);
    this._toast('▶ ' + path.split('/').pop());
  }

  // cameras and lights have no asset file — spawn them from the toolbar
  async _addRig(what){
    const D = {
      camera:    { kind:'camera', label:'camera', params:{ fov:45 }, transform:{ pos:[0,1.6,4], rot:[0,0,0], scale:1 } },
      keylight:  { kind:'light', label:'key light', params:{ type:'key', color:'#ffffff', intensity:2.2, castShadow:true }, transform:{ pos:[3,5,2], rot:[-0.9,0.5,0], scale:1 } },
      ambient:   { kind:'light', label:'ambient', params:{ type:'ambient', color:'#ffffff', intensity:1.0 } },
    }[what];
    const en = await this.stage.addEntity(D);
    this.stage.select(en.id);
    if(en.kind === 'camera') this.stage.setActiveCamera(en.id);   // preview through the new cam
  }

  // ---- inspector ----
  renderInspector(en){
    this._selId = en ? en.id : null;
    const el = this.insp; el.innerHTML = '';
    if(!en){ el.innerHTML = '<div class="empty">nothing selected</div>'; return; }
    const t = this.stage.entityTransform(en.id);
    const h = document.createElement('div'); h.className = 'ihd';
    h.innerHTML = `<b>${en.label}</b><span class="kind">${en.kind}${
      en.source && en.source.type === 'upload' ? ' · <span class="warn">upload</span>' : ''}</span>`;
    el.appendChild(h);

    el.appendChild(this._vec3('pos', t.pos, v => this.stage.setTransform(en.id, { pos:v })));
    el.appendChild(this._vec3('rot', t.rot, v => this.stage.setTransform(en.id, { rot:v })));
    el.appendChild(this._num('scale', t.scale, v => this.stage.setTransform(en.id, { scale:v })));

    if(en.kind === 'camera'){
      el.appendChild(this._num('fov', en.params.fov ?? 45, v => this.stage.setParam(en.id, 'fov', v)));
      const act = document.createElement('button'); act.textContent = '◉ set active camera'; act.className = 'wide';
      act.onclick = () => this.stage.setActiveCamera(en.id);
      el.appendChild(act);
    }
    if(en.kind === 'light'){
      el.appendChild(this._num('intensity', en.params.intensity ?? 1.5, v => this.stage.setParam(en.id, 'intensity', v)));
      el.appendChild(this._color('color', en.params.color || '#ffffff', v => this.stage.setParam(en.id, 'color', v)));
    }
    if(en.kind === 'backdrop')
      el.appendChild(this._sel('mode', ['plane','corner','dome'], en.params.mode || 'plane',
        v => this.stage.setParam(en.id, 'mode', v)));   // stage rebuilds the mesh on change

    const row = document.createElement('div'); row.className = 'ibtns';
    const key = document.createElement('button'); key.textContent = '⏺ key'; key.title = 'capture keyframe';
    key.onclick = () => dispatchEvent(new CustomEvent('scenegod:capturekey', { detail:{ id: en.id } }));
    const del = document.createElement('button'); del.textContent = '🗑 delete'; del.className = 'danger';
    del.onclick = () => { this.stage.removeEntity(en.id); this.renderInspector(null); };
    row.append(key, del); el.appendChild(row);
  }

  _field(label, inputEl){ const w = document.createElement('label'); w.className = 'fld';
    w.innerHTML = `<span>${label}</span>`; w.appendChild(inputEl); return w; }
  _num(label, val, cb){ const i = document.createElement('input'); i.type='number'; i.step='0.1'; i.value=val;
    i.oninput = () => cb(parseFloat(i.value) || 0); return this._field(label, i); }
  _color(label, val, cb){ const i = document.createElement('input'); i.type='color'; i.value=val;
    i.oninput = () => cb(i.value); return this._field(label, i); }
  _sel(label, opts, val, cb){ const s = document.createElement('select');
    for(const o of opts){ const op = document.createElement('option'); op.value=op.textContent=o; if(o===val) op.selected=true; s.appendChild(op); }
    s.onchange = () => cb(s.value); return this._field(label, s); }
  _vec3(label, arr, cb){ const w = document.createElement('div'); w.className = 'fld vec';
    w.innerHTML = `<span>${label}</span>`;
    const cur = [...arr];
    ['x','y','z'].forEach((_, k) => { const i = document.createElement('input'); i.type='number'; i.step='0.1'; i.value=+arr[k].toFixed(3);
      i.oninput = () => { cur[k] = parseFloat(i.value) || 0; cb([...cur]); }; w.appendChild(i); });
    return w; }

  // ---- local file drop (upload / offline path) ----
  _dropZone(){
    addEventListener('dragover', e => { e.preventDefault(); document.body.classList.add('hot'); });
    addEventListener('dragleave', e => { if(e.target === document.body) document.body.classList.remove('hot'); });
    addEventListener('drop', async e => {
      e.preventDefault(); document.body.classList.remove('hot');
      for(const f of e.dataTransfer.files){
        const nm = f.name.toLowerCase();
        try {
          if(/\.(png|jpe?g|webp)$/.test(nm)){
            const url = URL.createObjectURL(f);
            const en = await this.stage.addEntity({ kind:'backdrop', label:f.name,
              source:{ type:'upload', path:f.name, _url:url }, params:{ mode:'plane' } });
            this.stage.select(en.id);
          } else if(/\.(glb|gltf|fbx|obj|bvh)$/.test(nm)){
            const buf = await f.arrayBuffer();
            // clip drop onto selected character → bake; else load as a character
            const sel = this.stage.getEntity(this._selId);
            const probe = await this._probe(buf, f.name);
            if(sel && sel.kind === 'character' && probe.anims && !probe.meshes){
              // uploaded clip has no server path → the timeline can't place a block for it
              if(window.timeline){ this._toast('add clips from the dock, not local files, once the timeline is up'); }
              else {
                this._toast('baking ' + f.name + '…');
                const clip = await this.stage.prepareClipUpload(sel.id, buf, f.name, 0);
                this.stage.playClip(sel.id, clip); this._toast('▶ ' + f.name);
              }
            } else {
              const en = await this.stage.addEntity({ kind:'character', label:f.name,
                source:{ type:'upload', path:f.name }, _buf:buf });
              this.stage.select(en.id); this._toast('');
            }
          }
        } catch(err){ this._toast('drop failed: ' + String(err).slice(0, 100)); }
      }
    });
  }
  // cheap probe: is this file animation-only (clip) or a mesh (character)?
  async _probe(buf, name){
    const { parseAny } = await import('./room3d.js');
    const { root, anims } = await parseAny(buf.slice(0), name);
    const st = stats(root);
    return { anims: anims.length > 0, meshes: st.meshes };
  }

  _toast(m){ let t = document.getElementById('toast');
    if(!t){ t = document.createElement('div'); t.id = 'toast'; document.body.appendChild(t); }
    t.textContent = m; t.style.display = m ? 'block' : 'none';
    clearTimeout(this._th); if(m) this._th = setTimeout(() => t.style.display = 'none', 3500);
  }
}