/*******朗读开始********/

(function() {
  var changeState = function(o, old, n) {
    o.setAttribute("data-state", n);
    var clazz = o.getAttribute("class");
    if (clazz && clazz.length) {
      clazz = clazz.indexOf(old) >= 0
      ? clazz.replace(new RegExp(old, "gi"), n)
      : clazz + " " + n;
    } else {
      clazz = n;
    }
    o.setAttribute("class", clazz);
  };

  function newAudio(src, onended) {
    var audio = document.createElement("audio");
    audio.src = src;
    audio.preload = "auto";
    audio.onended = onended;
    audio.loop = false;
    return audio;
  }

  function V() {
    this.token = null;
    this.index = 0;
    this.playing = false;
    this.onend = null;

    this.srcs = [];

    this.audio = null;
    this.audio2 = null;
  }

  V.prototype = {
    start: function() {
      this.index = 0;
      this.playing = true;
      if (!this.audio) {
        this.audio = newAudio(this.srcs[0], this.next.bind(this));
        this.audio.load();
      } else {
        this.audio.src = this.srcs[0];
        this.audio.load();
      }
      if (this.srcs.length > 1) {
        if (!this.audio2) {
          this.audio2 = newAudio(this.srcs[1], this.next.bind(this));
          this.audio2.load();
        } else {
          this.audio2.src = this.srcs[1];
          this.audio2.load();
        }
      }
      this.audio.play();
    },
    resume: function() {
      if (this.playing) {
        this.audio.play();
      } else {
        this.start();
      }
    },
    pause: function() {
      if (this.playing) {
        this.audio.pause();
      }
    },
    next: function() {
      this.index++;
      while (this.index < this.srcs.length && !this.srcs[this.index] ) {
        // skip deleted
        this.index++;
      }
      if (this.index >= this.srcs.length) {
        this.playing = false;
        if (typeof this.onend === "function") this.onend();
        return;
      }
      var tmp = this.audio;
      this.audio = this.audio2;
      this.audio2 = tmp;
      if (this.srcs.length > this.index + 1) {
        this.audio2.src = this.srcs[this.index+1];
        this.audio2.load();
      }
      if (this.audio.duration > 0) {
        this.audio.play();
      } else {
        this.audio.src = "";
        this.audio.load();
        this.srcs[this.index] = undefined;
        this.next();
      }
    },
    onEnd: function(callback) {
      this.onend = callback;
    },
    init: function(text, callback) {
      var self = this;
      self.getToken(function(token) {
        self.index = 0;
        self.playing = false;
        var texts = text.match(/.{0,1000}/g);
        texts.forEach(function(t) {
          if (!t.length) return;
          self.srcs[self.srcs.length] = "http://tsn.baidu.com/text2audio?tok="
          + token + "&lan=zh&cuid=test&ctp=1&spd=5&pit=5&vol=8&per=0&tex="
          + encodeURIComponent(t);
        });
        self.start();
        self.audio.onloadeddata = function() {
          callback();
          self.audio.onloadeddata = undefined;
        }
      });
      return self;
    },

    getToken: function (callback) {
      var self = this;
      if (self.token) callback(self.token);
      else {
        var req = new XMLHttpRequest();
        req.addEventListener('load', function() {
          self.token = req.responseText;
          callback(self.token);
        });
        req.open("GET", "http://hanwen360.com/v");
        req.send();
      }
    },

    play: function(text) {
      var self = this;
      self.init(text, function() {
        self.start();
      });
    },

    ui: function(text) {
      var v = this;
      var con = document.createElement("div");
      con.setAttribute("id", "vui-con");
      var c = document.createElement("div");
      con.appendChild(c);
      c.setAttribute("id", "vui");
      // var state = "init";
      c.setAttribute("data-state", "init");
      c.addEventListener("click", function() {
        var old = c.getAttribute("data-state");
        var state;
        if (old === "init") {
          state = "loading";
          changeState(c, "init", "loading");
          v.init(text, function() {
            changeState(c, "loading", "playing");
          }).onEnd(function() {
            changeState(c, "playing", "stopped");
          });
        } else if (old === "playing") {
          state = "paused";
          v.pause();
          changeState(c, old, state);
        } else if (old === "paused") {
          state = "playing";
          v.resume();
          changeState(c, old, state);
        } else if (old === "stopped") {
          state = "playing";
          v.start();
          changeState(c, old, state);
        }
      });
      return con;
    }

  };
  window.V = V;
})();

$(document).ready(function() {
  var postTitle = $(".post-title");
  if (!postTitle.length) return;
  var text = postTitle.text() + "。" + $(".spider").text();
  if (!text.length) return;
  text = text.replace(/[ —]*/g, "").replace(/\n+/g, "。");
  var v = new V();
  postTitle.append(v.ui(text));
});

/*******朗读结束********/