/**
 * @license
 * Copyright (C) 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
(function() {
  'use strict';

  const SUGGESTIONS_LIMIT = 15;
  const REF_PREFIX = 'refs/heads/';

  /**
   * @appliesMixin Gerrit.URLEncodingMixin
   * @extends Polymer.Element
   */
  class GrRepoBranchPicker extends Polymer.mixinBehaviors( [
    Gerrit.URLEncodingBehavior,
  ], Polymer.GestureEventListeners(
      Polymer.LegacyElementMixin(
          Polymer.Element))) {
    static get is() { return 'gr-repo-branch-picker'; }

    static get properties() {
      return {
        repo: {
          type: String,
          notify: true,
          observer: '_repoChanged',
        },
        branch: {
          type: String,
          notify: true,
        },
        _branchDisabled: Boolean,
        _query: {
          type: Function,
          value() {
            return this._getRepoBranchesSuggestions.bind(this);
          },
        },
        _repoQuery: {
          type: Function,
          value() {
            return this._getRepoSuggestions.bind(this);
          },
        },
      };
    }

    /** @override */
    attached() {
      super.attached();
      if (this.repo) {
        this.$.repoInput.setText(this.repo);
      }
    }

    /** @override */
    ready() {
      super.ready();
      this._branchDisabled = !this.repo;
    }

    _getRepoBranchesSuggestions(input) {
      if (!this.repo) { return Promise.resolve([]); }
      if (input.startsWith(REF_PREFIX)) {
        input = input.substring(REF_PREFIX.length);
      }
      return this.$.restAPI.getRepoBranches(input, this.repo, SUGGESTIONS_LIMIT)
          .then(this._branchResponseToSuggestions.bind(this));
    }

    _getRepoSuggestions(input) {
      return this.$.restAPI.getRepos(input, SUGGESTIONS_LIMIT)
          .then(this._repoResponseToSuggestions.bind(this));
    }

    _repoResponseToSuggestions(res) {
      return res.map(repo => {
        return {
          name: repo.name,
          value: this.singleDecodeURL(repo.id),
        };
      });
    }

    _branchResponseToSuggestions(res) {
      return Object.keys(res).map(key => {
        let branch = res[key].ref;
        if (branch.startsWith(REF_PREFIX)) {
          branch = branch.substring(REF_PREFIX.length);
        }
        return {name: branch, value: branch};
      });
    }

    _repoCommitted(e) {
      this.repo = e.detail.value;
    }

    _branchCommitted(e) {
      this.branch = e.detail.value;
    }

    _repoChanged() {
      this.$.branchInput.clear();
      this._branchDisabled = !this.repo;
    }
  }

  customElements.define(GrRepoBranchPicker.is, GrRepoBranchPicker);
})();