/* ═════ 语音播报:my.createInnerAudioContext 播放远程 MP3 ═════
 * 文案/文件名契约:docs/语音播报内容设计文档_V1.0.md(A 步骤引导 / B 姿态提示 / C 流程音)
 * 播放策略与 H5 一致:单通道;流程音排队顺序播不互截;姿态提示同条 4s 去重、不打断流程音;
 * 资源远程化:{ASSET_BASE}voice/<id>.mp3;播放失败跳过,不阻断拍照。 */

var api = require('./api.js');

// A/B/C 三类清单(与 H5 app.js VOICE 常量一致)
var VOICE = {
  step: ['step1-front', 'step2-rightface', 'step3-leftface'],           // A. 步骤引导
  hint: {                                                               // B. 姿态提示(手动快门模式下基本不用,保留契约)
    '未检测到人脸': 'hint-noface', '请靠近一点': 'hint-near', '请远一点': 'hint-far',
    '请正对屏幕': 'hint-front', '请向左转头': 'hint-turn-left', '请向右转头': 'hint-turn-right',
    '保持不动': 'hint-hold'
  },
  countdown: 'countdown-321', shot: 'shot-done',                        // C. 拍摄与流程
  analyzing: 'analyzing', fail: 'analyze-fail'
};

var DEDUPE_MS = 4000; // 同条提示 4s 内不重复播

var audio = null;        // At most one live context; stopped contexts are never reused.
var lastAt = {};         // id → 上次开播时间(去重)
var cur = null;          // { id, kind:'flow'|'hint', audio }
var queue = [];          // 排队中的流程音
var pendingHint = null;  // 流程音期间挂起的姿态提示(只留最新)
var waiters = [];        // afterCurrent 回调:全部播报收尾后执行
var status = { version: 'VOICE-20261102-04', stage: 'idle', operation: 'none', errorType: 'none', id: '', code: 'NONE', category: 'none', reason: 'none',
  attempts: 0, canPlayEvents: 0, playEvents: 0, errorEvents: 0 };

function trace(stage, id, error) {
  status.stage = stage; status.id = id || '';
  if (error) {
    status.errorEvents++;
    status.errorType = /^(TypeError|ReferenceError|RangeError|Error)$/.test(error.name || '') ? error.name : 'NativeError';
    var code = error.errCode !== undefined ? error.errCode : error.errorCode !== undefined ? error.errorCode : error.error;
    status.code = typeof code === 'number' || typeof code === 'string' && /^[A-Za-z0-9_-]{1,32}$/.test(code) ? String(code) : 'UNAVAILABLE';
    var message = String(error.message || error.errorMessage || error.errMsg || '');
    status.reason = /appxDomain/i.test(message) ? 'APPX_DOMAIN_CONTEXT' : /white.?list|域名.*(允许|合法|白名单)|domain.*(allow|denied|invalid)/i.test(message) ? 'DOMAIN_REJECTED' :
      /TypeError|undefined|null/i.test(message) ? 'JS_CONTEXT_ERROR' : /not.support|unsupported|不支持/i.test(message) ? 'API_UNSUPPORTED' : 'UNCLASSIFIED';
    status.category = /domain|whitelist|域名/i.test(message) ? 'domain' : /permission|权限/i.test(message) ? 'permission' :
      /format|codec|decode|格式/i.test(message) ? 'decode' : /network|timeout|网络/i.test(message) ? 'network' :
      /unsupported|not.support|不支持/i.test(message) ? 'unsupported' : 'unknown';
  }
  // Fixed public clip IDs and numeric error codes only; never log returned
  // objects, media URLs, account identifiers, raw images or authorization data.
  try { if (typeof console !== 'undefined' && typeof console.info === 'function') console.info('[voice] ' + status.version +
    ' stage=' + stage + '; operation=' + status.operation + '; errorType=' + status.errorType + '; id=' + status.id + '; code=' + status.code + '; category=' + status.category + '; reason=' + status.reason); } catch (_) {}
}

function init() {
  if (audio) return;
  if (typeof my === 'undefined' || typeof my.createInnerAudioContext !== 'function') { trace('unavailable', '', { error: 'API_MISSING' }); return; }
  status.operation = 'create';
  try { audio = my.createInnerAudioContext(); } catch (error) { trace('create_failed', '', error); return; }
  if (!audio) return;
  // Hosts differ in writable properties. An unsupported property must never
  // prevent playback or escape into the camera page.
  try { audio.autoplay = false; } catch (_) {}
  try { audio.loop = false; } catch (_) {}
  try { audio.volume = 1; } catch (_) {}
  // Taobao's audio specification explicitly does not support obeyMuteSwitch.
}

function ensure() { if (!audio) init(); }

function playable(id) { return typeof id === 'string' && /^[a-z0-9-]+$/.test(id); }

function release(context, stop) {
  if (!context) return;
  if (audio === context) audio = null;
  if (stop) { try { if (typeof context.stop === 'function') context.stop(); } catch (_) {} }
  try { if (typeof context.destroy === 'function') context.destroy(); } catch (_) {}
}

function finish(record) {
  // Late ended/error notifications from an interrupted clip cannot finish the
  // current clip or drain its queue.
  if (cur !== record) return;
  cur = null; release(record.audio, false); drain();
}

function start(id, kind) {
  stopCur();
  ensure();
  if (!audio) { drain(); return; }
  lastAt[id] = Date.now();
  var context = audio, record = { id: id, kind: kind, audio: context, assigned: false, ready: false, requested: false };
  cur = record;
  status.attempts++; status.code = 'NONE'; status.category = 'none'; status.reason = 'none'; status.errorType = 'none'; trace('loading', id);
  function failed(error) { if (cur !== record) return; trace('error', id, error || { error: 'UNKNOWN' }); finish(record); }
  function requestPlay() {
    if (cur !== record || !record.assigned || !record.ready || record.requested) return;
    record.requested = true; status.operation = 'play'; trace('play_requested', id);
    try { var result = context.play(); if (result && typeof result.catch === 'function') result.catch(failed); }
    catch (error) { failed(error); }
  }
  try {
    status.operation = 'listen_ended';
    context.onEnded(function () { if (cur === record) trace('ended', id); finish(record); });
    status.operation = 'listen_error';
    context.onError(failed);
    status.operation = 'listen_play';
    if (typeof context.onPlay === 'function') context.onPlay(function () {
      if (cur !== record) return;
      record.requested = true; status.playEvents++; trace('playing', id);
    });
    var readyEvent = typeof context.onCanPlay === 'function' ? context.onCanPlay : context.onCanplay;
    status.operation = 'listen_canplay';
    if (typeof readyEvent === 'function') readyEvent.call(context, function () {
      if (cur !== record) return;
      record.ready = true; status.canPlayEvents++; trace('canplay', id); requestPlay();
    });
    else record.ready = true;
    status.operation = 'set_source';
    context.src = api.assetUrl('voice/' + id + '.mp3');
    record.assigned = true; requestPlay();
  } catch (error) {
    failed(error);
  }
}

function stopCur() {
  if (!cur) return;
  var record = cur; cur = null;
  release(record.audio, true);
}

function drain() {
  cur = null;
  if (queue.length) { start(queue.shift(), 'flow'); return; }
  if (pendingHint) { var h = pendingHint; pendingHint = null; start(h, 'hint'); return; }
  var w = waiters;
  waiters = [];
  w.forEach(function (fn) { fn(); });
}

function busyWithFlow() { return (cur && cur.kind === 'flow') || queue.length > 0; }

/**
 * 播报一条语音
 * @param {string} id 文件名(去 .mp3)
 * @param {object} [opts] hint:姿态提示(4s 去重);cut:打断在播与排队(失败提示用)
 */
function play(id, opts) {
  opts = opts || {};
  if (!playable(id)) return;
  if (opts.hint) {
    if (Object.prototype.hasOwnProperty.call(lastAt, id) && Date.now() - lastAt[id] < DEDUPE_MS) return;
    if (busyWithFlow()) { pendingHint = id; return; }
    start(id, 'hint');
    return;
  }
  if (opts.cut) { queue = []; pendingHint = null; stopCur(); start(id, 'flow'); return; }
  if (busyWithFlow()) { if (queue.indexOf(id) < 0) queue.push(id); return; }
  start(id, 'flow');
}

function dropHint() { pendingHint = null; } // 换步/提示清空:挂起的旧提示作废

// 流程切走:作废排队/挂起/等待;hard 连在播一并掐断(退出拍照页),否则让在播自然收尾(出报告)
function stop(hard) {
  queue = [];
  pendingHint = null;
  waiters = [];
  if (hard) { stopCur(); if (audio) release(audio, true); }
}

// 全部播报(含排队与挂起)自然收尾后执行 cb;空闲则立即执行
function afterCurrent(cb) {
  if (!cur && !queue.length && !pendingHint) { cb(); return; }
  waiters.push(cb);
}

module.exports = {
  VOICE: VOICE,
  init: init,
  play: play,
  dropHint: dropHint,
  stop: stop,
  afterCurrent: afterCurrent,
  diagnostics: function () { return Object.assign({}, status); }
};