// ==UserScript==
// @name         line-sticker-downloader
// @namespace    https://github.com/xingoxu/line-sticker-downloader
// @version      0.1.2
// @description  A line sticker downloader
// @author       xingoxu
// @match        https://store.line.me/stickershop/product/*
// @grant        none
// @downloadURL https://update.greasyfork.icu/scripts/21738/line-sticker-downloader.user.js
// @updateURL https://update.greasyfork.icu/scripts/21738/line-sticker-downloader.meta.js
// ==/UserScript==
(function($) {
  'use strict';
  var buttonHtml=`
  <a class="MdBtn01 mdBtn01" id="line-sticker-downloader-button" style="
    position: fixed;
    z-index: 9999;
    right: 30px;
    bottom: 0;
    ">
    <span class="mdBtn01Inner">
      <span class="mdBtn01Txt">Download</span>
    </span>
  </a>
  `;

  (function initFileSaver() {
    /* FileSaver.js
     * A saveAs() FileSaver implementation.
     * 1.3.2
     * 2016-06-16 18:25:19
     *
     * By Eli Grey, http://eligrey.com
     * License: MIT
     *   See https://github.com/eligrey/FileSaver.js/blob/master/LICENSE.md
     */

    /*global self */
    /*jslint bitwise: true, indent: 4, laxbreak: true, laxcomma: true, smarttabs: true, plusplus: true */

    /*! @source http://purl.eligrey.com/github/FileSaver.js/blob/master/FileSaver.js */

    var saveAs = saveAs || (function(view) {
      "use strict";
      // IE <10 is explicitly unsupported
      if (typeof view === "undefined" || typeof navigator !== "undefined" && /MSIE [1-9]\./.test(navigator.userAgent)) {
        return;
      }
      var
          doc = view.document
          // only get URL when necessary in case Blob.js hasn't overridden it yet
        , get_URL = function() {
          return view.URL || view.webkitURL || view;
        }
        , save_link = doc.createElementNS("http://www.w3.org/1999/xhtml", "a")
        , can_use_save_link = "download" in save_link
        , click = function(node) {
          var event = new MouseEvent("click");
          node.dispatchEvent(event);
        }
        , is_safari = /constructor/i.test(view.HTMLElement)
        , is_chrome_ios =/CriOS\/[\d]+/.test(navigator.userAgent)
        , throw_outside = function(ex) {
          (view.setImmediate || view.setTimeout)(function() {
            throw ex;
          }, 0);
        }
        , force_saveable_type = "application/octet-stream"
        // the Blob API is fundamentally broken as there is no "downloadfinished" event to subscribe to
        , arbitrary_revoke_timeout = 1000 * 40 // in ms
        , revoke = function(file) {
          var revoker = function() {
            if (typeof file === "string") { // file is an object URL
              get_URL().revokeObjectURL(file);
            } else { // file is a File
              file.remove();
            }
          };
          setTimeout(revoker, arbitrary_revoke_timeout);
        }
        , dispatch = function(filesaver, event_types, event) {
          event_types = [].concat(event_types);
          var i = event_types.length;
          while (i--) {
            var listener = filesaver["on" + event_types[i]];
            if (typeof listener === "function") {
              try {
                listener.call(filesaver, event || filesaver);
              } catch (ex) {
                throw_outside(ex);
              }
            }
          }
        }
        , auto_bom = function(blob) {
          // prepend BOM for UTF-8 XML and text/* types (including HTML)
          // note: your browser will automatically convert UTF-16 U+FEFF to EF BB BF
          if (/^\s*(?:text\/\S*|application\/xml|\S*\/\S*\+xml)\s*;.*charset\s*=\s*utf-8/i.test(blob.type)) {
            return new Blob([String.fromCharCode(0xFEFF), blob], {type: blob.type});
          }
          return blob;
        }
        , FileSaver = function(blob, name, no_auto_bom) {
          if (!no_auto_bom) {
            blob = auto_bom(blob);
          }
          // First try a.download, then web filesystem, then object URLs
          var
              filesaver = this
            , type = blob.type
            , force = type === force_saveable_type
            , object_url
            , dispatch_all = function() {
              dispatch(filesaver, "writestart progress write writeend".split(" "));
            }
            // on any filesys errors revert to saving with object URLs
            , fs_error = function() {
              if ((is_chrome_ios || (force && is_safari)) && view.FileReader) {
                // Safari doesn't allow downloading of blob urls
                var reader = new FileReader();
                reader.onloadend = function() {
                  var url = is_chrome_ios ? reader.result : reader.result.replace(/^data:[^;]*;/, 'data:attachment/file;');
                  var popup = view.open(url, '_blank');
                  if(!popup) view.location.href = url;
                  url=undefined; // release reference before dispatching
                  filesaver.readyState = filesaver.DONE;
                  dispatch_all();
                };
                reader.readAsDataURL(blob);
                filesaver.readyState = filesaver.INIT;
                return;
              }
              // don't create more object URLs than needed
              if (!object_url) {
                object_url = get_URL().createObjectURL(blob);
              }
              if (force) {
                view.location.href = object_url;
              } else {
                var opened = view.open(object_url, "_blank");
                if (!opened) {
                  // Apple does not allow window.open, see https://developer.apple.com/library/safari/documentation/Tools/Conceptual/SafariExtensionGuide/WorkingwithWindowsandTabs/WorkingwithWindowsandTabs.html
                  view.location.href = object_url;
                }
              }
              filesaver.readyState = filesaver.DONE;
              dispatch_all();
              revoke(object_url);
            }
          ;
          filesaver.readyState = filesaver.INIT;

          if (can_use_save_link) {
            object_url = get_URL().createObjectURL(blob);
            setTimeout(function() {
              save_link.href = object_url;
              save_link.download = name;
              click(save_link);
              dispatch_all();
              revoke(object_url);
              filesaver.readyState = filesaver.DONE;
            });
            return;
          }

          fs_error();
        }
        , FS_proto = FileSaver.prototype
        , saveAs = function(blob, name, no_auto_bom) {
          return new FileSaver(blob, name || blob.name || "download", no_auto_bom);
        }
      ;
      // IE 10+ (native saveAs)
      if (typeof navigator !== "undefined" && navigator.msSaveOrOpenBlob) {
        return function(blob, name, no_auto_bom) {
          name = name || blob.name || "download";

          if (!no_auto_bom) {
            blob = auto_bom(blob);
          }
          return navigator.msSaveOrOpenBlob(blob, name);
        };
      }

      FS_proto.abort = function(){};
      FS_proto.readyState = FS_proto.INIT = 0;
      FS_proto.WRITING = 1;
      FS_proto.DONE = 2;

      FS_proto.error =
      FS_proto.onwritestart =
      FS_proto.onprogress =
      FS_proto.onwrite =
      FS_proto.onabort =
      FS_proto.onerror =
      FS_proto.onwriteend =
        null;

      return saveAs;
    }(
         typeof self !== "undefined" && self
      || typeof window !== "undefined" && window
      || this.content
    ));
    // `self` is undefined in Firefox for Android content script context
    // while `this` is nsIContentFrameMessageManager
    // with an attribute `content` that corresponds to the window

    window.saveAs = saveAs;
  })();

  function getURL() {
    console.log('Get URLing...');

    var firstAndLastNode = Array.prototype.slice.call($('ul.FnSticker_animation_list_img li:first-child span,ul.FnSticker_animation_list_img li:last-child span'));
    var imageURL = ""; //url前缀
    firstAndLastNode.forEach(function(value, index, array) {
      var backgroundImage = value.style.backgroundImage,
        lastIndex = backgroundImage.lastIndexOf('/');
      imageURL = backgroundImage.substring(backgroundImage.indexOf('http'), lastIndex + 1);
      firstAndLastNode[index] = backgroundImage.substring(lastIndex + 1, backgroundImage.lastIndexOf('.'));
    });

    if(firstAndLastNode.length<=1){
      console.log('No Matched Nodes...Exiting...');
      return;
    }

    return {
      first: Number.parseInt(firstAndLastNode[0]),
      last: Number.parseInt(firstAndLastNode[1]),
      url: imageURL
    };
  }

  function download(url,callback) {
    var xhr = new XMLHttpRequest();
    xhr.onreadystatechange = function() {
      if (this.readyState == 4 && this.status == 200) {
        //this.response is what you're looking for
        console.log('Got the Blob!');
        callback(this.response);
      }
    };
    xhr.open('GET', url);
    xhr.responseType = 'blob';
    xhr.send();
  }
  var urls=getURL();
  if(!urls) {
    return;
  }

  //is Downloading
  var isDownloading = false;

  //appendButton
  $('body').prepend(buttonHtml);

  //attachClickHandler
  $('#line-sticker-downloader-button').click(function(event) {
    if (isDownloading) return;
    var $button = $(this);
    //show Downloading...
    isDownloading = true;
    $button.find('.mdBtn01Txt').text('Downloading...');

    (Promise.resolve(urls))
    .then(function(ids) {
        'use strict';
        if (ids.first > ids.last) {
          let temp = first;
          first = last;
          last = temp;
        }

        console.log('Downloading...');

        var promiseArray=[];
        for (var i = ids.first; i <= ids.last; i++) {
          (function(i) {
            var promise=(new Promise(function(resolve, reject) {
              download(ids.url + i + '.png', function(blob) {
                resolve(blob);
              });
            }))
            .then(function(blob) {
                console.log('Saving...');
                saveAs(blob,i + '.png');
              })
            .catch(function(err) {
              console.log(err);
            });

            promiseArray.push(promise);
          })(i);
        }
        return Promise.all(promiseArray);
      })
    .then(function() {
      $button.find('.mdBtn01Txt').text('Complete!');
      setTimeout(function() {
        $button.find('.mdBtn01Txt').text('Download');
      }, 5000);
    })
    .catch(function(err) {
      $button.find('.mdBtn01Txt').text('Error!');
      console.log(err);
    })
    .then(function() {
      isDownloading = false;
    });
  });
})(jQuery);