/**
 * VIGNETTE MODEL — the pure, Node-testable rules of data/vignettes.json.
 *
 * A vignette is a DIALOGUE SCENE that plays on a planet's surface (the
 * SurfaceScene), triggered by the world's location buttons (the EXPLORE
 * drawer's Bar, the SHOP deck slot): a sequence of lines, each with a
 * speaker + text + an optional speech clip, played in a window centered
 * on the screen over the location's looping clip (js/ui/VignetteWindow.js).
 *
 *   { id, location, quest?, step?, once,
 *     effects?: { cargoHold? },          // the DONE press's story beat (pure data — GameScene applies it)
 *     lines: [{ from, text, audio? }] }
 *
 * This module normalizes the config (dropping — with a console warning —
 * anything that can't be shown) and answers the questions the hub asks:
 *
 *   - `vignettesForLocation(cfg, location)` — which scenes are bound to a
 *     world slot ('bar', 'shop', …), in config order;
 *   - `vignetteAvailable(vig, state)` — is this one playable NOW, against
 *     a state snapshot the scene builds from the sleeping GameScene (the
 *     run's played ledger + the gate's quest facts — see below);
 *   - `lineAssets(cfg, line)` / `vignetteAssets(cfg, vig)` — the
 *     deferred-load specs: the speaker's PLANET clip (by character id, so
 *     every line from Carol shares one cached clip) and each speech clip
 *     (by file, so a clip shared by several lines loads once).
 *
 * THE GATE (vignettes are quest steps): a vignette names the quest it is
 * a step of (`quest` + the step's index `step`). It is AVAILABLE while
 * that quest is granted and unclaimed and the step is still OPEN — and
 * finishing the scene is the step's WITNESS (GameScene._questCheckEval's
 * 'vignettePlayed' check reads the run's played ledger — the same shape
 * as the comms' trestleTalked/trestleMet). A vignette with no gate plays
 * on every visit (until its ledger mark).
 *
 * Pure: it takes the `vignettes` config SECTION (the object from
 * data/vignettes.json) — never the `config` singleton — so the dev tests
 * (dev/vignettes.test.mjs) can feed it plain JSON.
 *
 *   import { config } from '../config/Config.js';
 *   const cfg = config.section('vignettes', {});
 *   const scenes = vignettesForLocation(cfg, 'bar');
 */

/** The scene-loader cache key for a character's PLANET clip: vign_vid_<id>. */
export function videoKeyFor(charId) {
  return `vign_vid_${String(charId)}`;
}

/**
 * A character's PLANET clip URL — the planet cut of the comms' space cut:
 * assets/videos/characters/planet-<id>.mp4 (planet-trestle.mp4 vs the
 * comms' trestle.mp4). A character entry may override it with its own
 * `video` (lineAssets applies the override).
 */
export function videoUrlFor(charId) {
  return `assets/videos/characters/planet-${String(charId)}.mp4`;
}

/**
 * The scene-loader cache key for a speech clip, derived from the FILE
 * (the comms' audioKeyFor recipe, the vignettes' prefix): the key is the
 * folder + basename (two lines sharing a clip share one key; the folder
 * is part of the key because TWO CHARACTERS may both ship an
 * 'intro-01.mp3' — the basename alone would make Carol speak Trestle's
 * clip (the loader would see the key as already loaded)).
 */
export function audioKeyFor(file) {
  const parts = String(file ?? '')
    .split('/')
    .filter(Boolean);
  const base = (parts.pop() ?? '').replace(/\.[a-z0-9]+$/i, '');
  const dir = parts.length ? parts[parts.length - 1] : null;
  const safe = `${dir ? dir + '-' : ''}${base}`.replace(/[^a-z0-9_-]+/gi, '-');
  return `vign_au_${safe || 'speech'}`;
}

/** @returns {boolean} the master switch (a config predating vignettes defaults on). */
export function vignettesEnabled(cfg) {
  return cfg?.enabled !== false;
}

/**
 * The speaker's entry (characters.<from>) or null (a line from an unknown
 * speaker makes its vignette unplayable — the window has no face to put
 * on it).
 */
export function charEntry(cfg, from) {
  const chars = cfg?.characters;
  if (!chars || typeof chars !== 'object' || from == null) return null;
  const entry = chars[from];
  return entry && typeof entry === 'object' ? entry : null;
}

/**
 * Normalize one line: a clean object, or null when it can't be spoken
 * (with a console warning).
 *
 * Rules:
 *   - from: must name a speaker (the caller checks the character entry —
 *     a faceless line makes the whole scene unplayable);
 *   - text: required (a line with no words is noise);
 *   - audio: an optional speech clip (a text-only line is a valid line).
 */
export function normalizeLine(raw) {
  if (!raw || typeof raw !== 'object') return null;
  const from = String(raw.from ?? '').trim();
  if (!from) {
    console.warn('[vignettes] a line has no speaker — dropped');
    return null;
  }
  const text = String(raw.text ?? '').trim();
  if (!text) {
    console.warn(`[vignettes] a line from "${from}" has no text — dropped`);
    return null;
  }
  const audio = String(raw.audio ?? '').trim();
  return { from, text, audio: audio || null };
}

/**
 * Normalize one vignette entry: returns a clean object, or null when the
 * scene can't be shown (with a console warning — the rest of the roster
 * still plays).
 *
 * Rules:
 *   - id: required (the played ledger + the quest's 'vignettePlayed'
 *     witness both key off it);
 *   - location: a non-empty string, lowercased (the world slot that
 *     triggers it — 'bar', 'shop', …);
 *   - lines: at least ONE playable line with a known speaker (a half
 *     scene is worse than no scene — one bad line drops the whole
 *     vignette, warned per line);
 *   - quest: optional (no gate = the scene plays on every visit); when
 *     present it must name a non-empty quest id;
 *   - step: the gate's step index (default 0, clamped to >= 0);
 *   - effects: the story beat the DONE press runs (a plain object —
 *     normalizeEffects keeps the safe entries: cargoHold = a positive
 *     bay count; the run's ship starts with cargoHold 0 (data/ship.json)
 *     and the scene's lines are the truth — Carol's crew builds the bays).
 *     GameScene.onVignetteComplete applies it, BEFORE the scene's quest
 *     package handoff (the hold must fit the package);
 *   - once defaults true (a scene plays once per run; `once: false`
 *     re-arms on every visit — the author's repeat).
 *
 * @param {object} raw the config entry (data/vignettes.json → vignettes[])
 * @param {object} [cfg] the vignettes config section (for the characters
 *   table — the line speaker check; plain JSON in the dev tests)
 */
export function normalizeVignette(raw, cfg) {
  if (!raw || typeof raw !== 'object') return null;
  const id = String(raw.id ?? '').trim();
  if (!id) {
    console.warn('[vignettes] a scene has no id — dropped');
    return null;
  }
  const location = String(raw.location ?? '').trim().toLowerCase();
  if (!location) {
    console.warn(`[vignettes] "${id}" has no location — dropped`);
    return null;
  }
  const quest = String(raw.quest ?? '').trim();
  const step = Math.max(0, Math.round(Number(raw.step) || 0));
  const rawLines = Array.isArray(raw.lines) ? raw.lines : [];
  if (rawLines.length === 0) {
    console.warn(`[vignettes] "${id}" has no lines — dropped`);
    return null;
  }
  const lines = [];
  for (const rl of rawLines) {
    const line = normalizeLine(rl);
    if (!line) return null; // one bad line drops the whole scene (warned above)
    if (!charEntry(cfg, line.from)) {
      console.warn(`[vignettes] "${id}" has a line for unknown speaker "${line.from}" — dropped`);
      return null;
    }
    lines.push(line);
  }
  return {
    id,
    location,
    quest: quest || null,
    step: quest ? step : null,
    once: raw.once !== false,
    effects: normalizeEffects(raw.effects),
    lines,
  };
}

/**
 * The scene's story effects (data/vignettes.json → vignettes[].effects) —
 * the beat the DONE press runs BEFORE the location resumes. Pure data:
 * the model keeps the safe entries, GameScene.onVignetteComplete applies
 * them.
 *
 *   cargoHold — the ship's unlocked cargo bays (a positive integer; the
 *               run's ship starts with 0 — data/ship.json — and the
 *               application is MAX-wins, never a downgrade).
 *
 * @returns {object|null} the clean effects, or null when none survived
 */
export function normalizeEffects(raw) {
  if (!raw || typeof raw !== 'object') return null;
  const out = {};
  const hold = Number(raw.cargoHold);
  if (Number.isFinite(hold) && hold > 0) out.cargoHold = Math.floor(hold);
  if (Object.keys(out).length === 0) return null;
  return out;
}

/**
 * The playable roster: the normalized vignettes in config order, minus
 * the unplayable ones (warned per id). The characters table rides in
 * `cfg.characters` (data/vignettes.json).
 * @returns {Array<object>}
 */
export function listVignettes(cfg) {
  const list = Array.isArray(cfg?.vignettes) ? cfg.vignettes : [];
  const out = [];
  const seen = new Set();
  for (const raw of list) {
    if (typeof raw === 'string' || raw == null) continue; // $comment strings, etc.
    const vig = normalizeVignette(raw, cfg);
    if (!vig) continue;
    if (seen.has(vig.id)) {
      console.warn(`[vignettes] duplicate id "${vig.id}" — the first entry wins`);
      continue;
    }
    seen.add(vig.id);
    out.push(vig);
  }
  return out;
}

/**
 * The roster's scenes bound to a location, in config order.
 * @param {string} location the world slot id ('bar', 'shop', … — case-insensitive)
 * @returns {Array<object>} the normalized vignettes
 */
export function vignettesForLocation(cfg, location) {
  const name = String(location ?? '').trim().toLowerCase();
  if (!name) return [];
  return listVignettes(cfg).filter((v) => v.location === name);
}

/**
 * Is the scene playable NOW? Pure against a state snapshot the scene
 * builds (the hub adds the run's played ledger; the scene supplies the
 * gate's facts from the sleeping GameScene):
 *
 *   state = {
 *     played: Set,            the run's already-played ids (registry 'vignettesPlayed')
 *     gate: null | {          null = no gate (an ungated scene) / the scene
 *       granted: boolean,     couldn't read the ledger — a gated scene
 *       claimed: boolean,     then stays UNAVAILABLE (a gate it can't
 *       stepExists: boolean,  verify must not open a scene)
 *       stepDone: boolean,
 *     },
 *   }
 *
 * Available = not already played (for `once` scenes) AND (no gate, or
 * the gate is held: the quest is granted, unclaimed, its step exists and
 * is still open).
 *
 * @returns {boolean}
 */
export function vignetteAvailable(vig, state = {}) {
  if (!vig) return false;
  const played = state.played instanceof Set ? state.played : new Set();
  if (vig.once && played.has(vig.id)) return false;
  if (!vig.quest) return true; // ungated — the location plays it (once not played)
  const gate = state.gate;
  if (!gate || typeof gate !== 'object') return false; // gated + unreadable → unavailable
  return (
    gate.granted === true &&
    gate.claimed !== true &&
    gate.stepExists === true &&
    gate.stepDone !== true
  );
}

/**
 * The line's deferred-load spec. The character clip is keyed BY CHARACTER
 * (every Carol line shares one cached clip — her planet cut); the speech
 * clip BY FILE (a clip reused across lines loads once).
 *
 * @returns {{video: {key:string,url:string}|null, audio: {key:string,url:string}|null}}
 */
export function lineAssets(cfg, line) {
  const entry = charEntry(cfg, line.from);
  const videoUrl = String(entry?.video ?? '').trim() || videoUrlFor(line.from);
  const audioUrl = String(line?.audio ?? '').trim();
  return {
    video: { key: videoKeyFor(line.from), url: videoUrl },
    audio: audioUrl ? { key: audioKeyFor(audioUrl), url: audioUrl } : null,
  };
}

/**
 * The vignette's full deferred-load spec (the hub's one load pass): every
 * distinct character clip + speech file its lines need, deduped by cache
 * key (a two-beat Carol scene fetches her clip once).
 *
 * @returns {{videos: Array<{key:string,url:string}>, audios: Array<{key:string,url:string}>}}
 */
export function vignetteAssets(cfg, vig) {
  const videos = new Map();
  const audios = new Map();
  for (const line of vig.lines ?? []) {
    const a = lineAssets(cfg, line);
    if (a.video) videos.set(a.video.key, a.video);
    if (a.audio) audios.set(a.audio.key, a.audio);
  }
  return { videos: [...videos.values()], audios: [...audios.values()] };
}