/* eslint-disable func-names, space-before-function-paren, no-template-curly-in-string, comma-dangle, object-shorthand, quotes, dot-notation, no-else-return, one-var, no-var, no-underscore-dangle, one-var-declaration-per-line, no-param-reassign, no-useless-escape, prefer-template, consistent-return, wrap-iife, prefer-arrow-callback, camelcase, no-unused-vars, no-useless-return, vars-on-top, max-len */

import emojiMap from 'emojis/digests.json';
import emojiAliases from 'emojis/aliases.json';
import { glEmojiTag } from '~/behaviors/gl_emoji';
import glRegexp from '~/lib/utils/regexp';

// Creates the variables for setting up GFM auto-completion
window.gl = window.gl || {};

function sanitize(str) {
  return str.replace(/<(?:.|\n)*?>/gm, '');
}

window.gl.GfmAutoComplete = {
  dataSources: {},
  defaultLoadingData: ['loading'],
  cachedData: {},
  isLoadingData: {},
  atTypeMap: {
    ':': 'emojis',
    '@': 'members',
    '#': 'issues',
    '!': 'mergeRequests',
    '~': 'labels',
    '%': 'milestones',
    '/': 'commands'
  },
  // Emoji
  Emoji: {
    templateFunction: function(name) {
      return `<li>
        ${name} ${glEmojiTag(name)}
      </li>
      `;
    }
  },
  // Team Members
  Members: {
    template: '<li>${avatarTag} ${username} <small>${title}</small></li>'
  },
  Labels: {
    template: '<li><span class="dropdown-label-box" style="background: ${color}"></span> ${title}</li>'
  },
  // Issues and MergeRequests
  Issues: {
    template: '<li><small>${id}</small> ${title}</li>'
  },
  // Milestones
  Milestones: {
    template: '<li>${title}</li>'
  },
  Loading: {
    template: '<li style="pointer-events: none;"><i class="fa fa-spinner fa-spin"></i> Loading...</li>'
  },
  DefaultOptions: {
    sorter: function(query, items, searchKey) {
      this.setting.highlightFirst = this.setting.alwaysHighlightFirst || query.length > 0;
      if (gl.GfmAutoComplete.isLoading(items)) {
        this.setting.highlightFirst = false;
        return items;
      }
      return $.fn.atwho["default"].callbacks.sorter(query, items, searchKey);
    },
    filter: function(query, data, searchKey) {
      if (gl.GfmAutoComplete.isLoading(data)) {
        gl.GfmAutoComplete.fetchData(this.$inputor, this.at);
        return data;
      } else {
        return $.fn.atwho["default"].callbacks.filter(query, data, searchKey);
      }
    },
    beforeInsert: function(value) {
      if (value && !this.setting.skipSpecialCharacterTest) {
        var withoutAt = value.substring(1);
        if (withoutAt && /[^\w\d]/.test(withoutAt)) value = value.charAt() + '"' + withoutAt + '"';
      }
      return value;
    },
    matcher: function (flag, subtext) {
      // The below is taken from At.js source
      // Tweaked to commands to start without a space only if char before is a non-word character
      // https://github.com/ichord/At.js
      var _a, _y, regexp, match, atSymbolsWithBar, atSymbolsWithoutBar;
      atSymbolsWithBar = Object.keys(this.app.controllers).join('|');
      atSymbolsWithoutBar = Object.keys(this.app.controllers).join('');
      subtext = subtext.split(/\s+/g).pop();
      flag = flag.replace(/[\-\[\]\/\{\}\(\)\*\+\?\.\\\^\$\|]/g, "\\$&");

      _a = decodeURI("%C3%80");
      _y = decodeURI("%C3%BF");

      regexp = new RegExp("^(?:\\B|[^a-zA-Z0-9_" + atSymbolsWithoutBar + "]|\\s)" + flag + "(?!" + atSymbolsWithBar + ")((?:[A-Za-z" + _a + "-" + _y + "0-9_\'\.\+\-]|[^\\x00-\\x7a])*)$", 'gi');

      match = regexp.exec(subtext);

      if (match) {
        return match[1];
      } else {
        return null;
      }
    }
  },
  setup: function(input, enableMap = {
    emojis: true,
    members: true,
    issues: true,
    milestones: true,
    mergeRequests: true,
    labels: true
  }) {
    // Add GFM auto-completion to all input fields, that accept GFM input.
    this.input = input || $('.js-gfm-input');
    this.enableMap = enableMap;
    this.setupLifecycle();
  },
  setupLifecycle() {
    this.input.each((i, input) => {
      const $input = $(input);
      $input.off('focus.setupAtWho').on('focus.setupAtWho', this.setupAtWho.bind(this, $input));
      // This triggers at.js again
      // Needed for slash commands with suffixes (ex: /label ~)
      $input.on('inserted-commands.atwho', $input.trigger.bind($input, 'keyup'));
    });
  },

  setupAtWho: function($input) {
    if (this.enableMap.emojis) this.setupEmoji($input);
    if (this.enableMap.members) this.setupMembers($input);
    if (this.enableMap.issues) this.setupIssues($input);
    if (this.enableMap.milestones) this.setupMilestones($input);
    if (this.enableMap.mergeRequests) this.setupMergeRequests($input);
    if (this.enableMap.labels) this.setupLabels($input);

    // We don't instantiate the slash commands autocomplete for note and issue/MR edit forms
    $input.filter('[data-supports-slash-commands="true"]').atwho({
      at: '/',
      alias: 'commands',
      searchKey: 'search',
      skipSpecialCharacterTest: true,
      data: this.defaultLoadingData,
      displayTpl: function(value) {
        if (this.isLoading(value)) return this.Loading.template;
        var tpl = '<li>/${name}';
        if (value.aliases.length > 0) {
          tpl += ' <small>(or /<%- aliases.join(", /") %>)</small>';
        }
        if (value.params.length > 0) {
          tpl += ' <small><%- params.join(" ") %></small>';
        }
        if (value.description !== '') {
          tpl += '<small class="description"><i><%- description %></i></small>';
        }
        tpl += '</li>';
        return _.template(tpl)(value);
      }.bind(this),
      insertTpl: function(value) {
        var tpl = "/${name} ";
        var reference_prefix = null;
        if (value.params.length > 0) {
          reference_prefix = value.params[0][0];
          if (/^[@%~]/.test(reference_prefix)) {
            tpl += '<%- reference_prefix %>';
          }
        }
        return _.template(tpl)({ reference_prefix: reference_prefix });
      },
      suffix: '',
      callbacks: {
        sorter: this.DefaultOptions.sorter,
        filter: this.DefaultOptions.filter,
        beforeInsert: this.DefaultOptions.beforeInsert,
        beforeSave: function(commands) {
          if (gl.GfmAutoComplete.isLoading(commands)) return commands;
          return $.map(commands, function(c) {
            var search = c.name;
            if (c.aliases.length > 0) {
              search = search + " " + c.aliases.join(" ");
            }
            return {
              name: c.name,
              aliases: c.aliases,
              params: c.params,
              description: c.description,
              search: search
            };
          });
        },
        matcher: function(flag, subtext, should_startWithSpace, acceptSpaceBar) {
          var regexp = /(?:^|\n)\/([A-Za-z_]*)$/gi;
          var match = regexp.exec(subtext);
          if (match) {
            return match[1];
          } else {
            return null;
          }
        }
      }
    });
    return;
  },

  setupEmoji($input) {
    // Emoji
    $input.atwho({
      at: ':',
      displayTpl: function(value) {
        return value && value.name ? this.Emoji.templateFunction(value.name) : this.Loading.template;
      }.bind(this),
      insertTpl: ':${name}:',
      skipSpecialCharacterTest: true,
      data: this.defaultLoadingData,
      callbacks: {
        sorter: this.DefaultOptions.sorter,
        beforeInsert: this.DefaultOptions.beforeInsert,
        filter: this.DefaultOptions.filter,

        matcher: (flag, subtext) => {
          const relevantText = subtext.trim().split(/\s/).pop();
          const regexp = new RegExp(`(?:[^${glRegexp.unicodeLetters}0-9:]|\n|^):([^:]*)$`, 'gi');
          const match = regexp.exec(relevantText);

          return match && match.length ? match[1] : null;
        }
      }
    });
  },

  setupMembers($input) {
    // Team Members
    $input.atwho({
      at: '@',
      displayTpl: function(value) {
        return value.username != null ? this.Members.template : this.Loading.template;
      }.bind(this),
      insertTpl: '${atwho-at}${username}',
      searchKey: 'search',
      alwaysHighlightFirst: true,
      skipSpecialCharacterTest: true,
      data: this.defaultLoadingData,
      callbacks: {
        sorter: this.DefaultOptions.sorter,
        filter: this.DefaultOptions.filter,
        beforeInsert: this.DefaultOptions.beforeInsert,
        matcher: this.DefaultOptions.matcher,
        beforeSave: function(members) {
          return $.map(members, function(m) {
            let title = '';
            if (m.username == null) {
              return m;
            }
            title = m.name;
            if (m.count) {
              title += " (" + m.count + ")";
            }

            const autoCompleteAvatar = m.avatar_url || m.username.charAt(0).toUpperCase();
            const imgAvatar = `<img src="${m.avatar_url}" alt="${m.username}" class="avatar avatar-inline center s26"/>`;
            const txtAvatar = `<div class="avatar center avatar-inline s26">${autoCompleteAvatar}</div>`;

            return {
              username: m.username,
              avatarTag: autoCompleteAvatar.length === 1 ? txtAvatar : imgAvatar,
              title: sanitize(title),
              search: sanitize(m.username + " " + m.name)
            };
          });
        }
      }
    });
  },

  setupIssues($input) {
    $input.atwho({
      at: '#',
      alias: 'issues',
      searchKey: 'search',
      displayTpl: function(value) {
        return value.title != null ? this.Issues.template : this.Loading.template;
      }.bind(this),
      data: this.defaultLoadingData,
      insertTpl: '${atwho-at}${id}',
      callbacks: {
        sorter: this.DefaultOptions.sorter,
        filter: this.DefaultOptions.filter,
        beforeInsert: this.DefaultOptions.beforeInsert,
        matcher: this.DefaultOptions.matcher,
        beforeSave: function(issues) {
          return $.map(issues, function(i) {
            if (i.title == null) {
              return i;
            }
            return {
              id: i.iid,
              title: sanitize(i.title),
              search: i.iid + " " + i.title
            };
          });
        }
      }
    });
  },

  setupMilestones($input) {
    $input.atwho({
      at: '%',
      alias: 'milestones',
      searchKey: 'search',
      insertTpl: '${atwho-at}${title}',
      displayTpl: function(value) {
        return value.title != null ? this.Milestones.template : this.Loading.template;
      }.bind(this),
      data: this.defaultLoadingData,
      callbacks: {
        matcher: this.DefaultOptions.matcher,
        sorter: this.DefaultOptions.sorter,
        beforeInsert: this.DefaultOptions.beforeInsert,
        filter: this.DefaultOptions.filter,
        beforeSave: function(milestones) {
          return $.map(milestones, function(m) {
            if (m.title == null) {
              return m;
            }
            return {
              id: m.iid,
              title: sanitize(m.title),
              search: "" + m.title
            };
          });
        }
      }
    });
  },

  setupMergeRequests($input) {
    $input.atwho({
      at: '!',
      alias: 'mergerequests',
      searchKey: 'search',
      displayTpl: function(value) {
        return value.title != null ? this.Issues.template : this.Loading.template;
      }.bind(this),
      data: this.defaultLoadingData,
      insertTpl: '${atwho-at}${id}',
      callbacks: {
        sorter: this.DefaultOptions.sorter,
        filter: this.DefaultOptions.filter,
        beforeInsert: this.DefaultOptions.beforeInsert,
        matcher: this.DefaultOptions.matcher,
        beforeSave: function(merges) {
          return $.map(merges, function(m) {
            if (m.title == null) {
              return m;
            }
            return {
              id: m.iid,
              title: sanitize(m.title),
              search: m.iid + " " + m.title
            };
          });
        }
      }
    });
  },

  setupLabels($input) {
    $input.atwho({
      at: '~',
      alias: 'labels',
      searchKey: 'search',
      data: this.defaultLoadingData,
      displayTpl: function(value) {
        return this.isLoading(value) ? this.Loading.template : this.Labels.template;
      }.bind(this),
      insertTpl: '${atwho-at}${title}',
      callbacks: {
        matcher: this.DefaultOptions.matcher,
        beforeInsert: this.DefaultOptions.beforeInsert,
        filter: this.DefaultOptions.filter,
        sorter: this.DefaultOptions.sorter,
        beforeSave: function(merges) {
          if (gl.GfmAutoComplete.isLoading(merges)) return merges;
          var sanitizeLabelTitle;
          sanitizeLabelTitle = function(title) {
            if (/[\w\?&]+\s+[\w\?&]+/g.test(title)) {
              return "\"" + (sanitize(title)) + "\"";
            } else {
              return sanitize(title);
            }
          };
          return $.map(merges, function(m) {
            return {
              title: sanitize(m.title),
              color: m.color,
              search: "" + m.title
            };
          });
        }
      }
    });
  },

  fetchData: function($input, at) {
    if (this.isLoadingData[at]) return;
    this.isLoadingData[at] = true;
    if (this.cachedData[at]) {
      this.loadData($input, at, this.cachedData[at]);
    } else if (this.atTypeMap[at] === 'emojis') {
      this.loadData($input, at, Object.keys(emojiMap).concat(Object.keys(emojiAliases)));
    } else {
      $.getJSON(this.dataSources[this.atTypeMap[at]], (data) => {
        this.loadData($input, at, data);
      }).fail(() => { this.isLoadingData[at] = false; });
    }
  },
  loadData: function($input, at, data) {
    this.isLoadingData[at] = false;
    this.cachedData[at] = data;
    $input.atwho('load', at, data);
    // This trigger at.js again
    // otherwise we would be stuck with loading until the user types
    return $input.trigger('keyup');
  },
  isLoading(data) {
    var dataToInspect = data;
    if (data && data.length > 0) {
      dataToInspect = data[0];
    }

    var loadingState = this.defaultLoadingData[0];
    return dataToInspect &&
      (dataToInspect === loadingState || dataToInspect.name === loadingState);
  }
};
