// 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.

import m from 'mithril';

import {classNames} from '../base/classnames';
import {raf} from '../core/raf_scheduler';

import {globals} from './globals';
import {taskTracker} from './task_tracker';

export const DISMISSED_PANNING_HINT_KEY = 'dismissedPanningHint';

class Progress implements m.ClassComponent {
  view(_vnode: m.Vnode): m.Children {
    const classes = classNames(this.isLoading() && 'progress-anim');
    return m('.progress', {class: classes});
  }

  private isLoading(): boolean {
    const engine = globals.getCurrentEngine();
    return (
      (engine && !engine.ready) ||
      globals.numQueuedQueries > 0 ||
      taskTracker.hasPendingTasks()
    );
  }
}

class HelpPanningNotification implements m.ClassComponent {
  view() {
    const dismissed = localStorage.getItem(DISMISSED_PANNING_HINT_KEY);
    // Do not show the help notification in embedded mode because local storage
    // does not persist for iFrames. The host is responsible for communicating
    // to users that they can press '?' for help.
    if (
      globals.embeddedMode ||
      dismissed === 'true' ||
      !globals.showPanningHint
    ) {
      return;
    }
    return m(
      '.helpful-hint',
      m(
        '.hint-text',
        'Are you trying to pan? Use the WASD keys or hold shift to click ' +
          "and drag. Press '?' for more help.",
      ),
      m(
        'button.hint-dismiss-button',
        {
          onclick: () => {
            globals.showPanningHint = false;
            localStorage.setItem(DISMISSED_PANNING_HINT_KEY, 'true');
            raf.scheduleFullRedraw();
          },
        },
        'Dismiss',
      ),
    );
  }
}

class TraceErrorIcon implements m.ClassComponent {
  view() {
    if (globals.embeddedMode) return;

    const mode = globals.state.omniboxState.mode;

    const errors = globals.traceErrors;
    if ((!Boolean(errors) && !globals.metricError) || mode === 'COMMAND') {
      return;
    }
    const message = Boolean(errors)
      ? `${errors} import or data loss errors detected.`
      : `Metric error detected.`;
    return m(
      'a.error',
      {href: '#!/info'},
      m(
        'i.material-icons',
        {
          title: message + ` Click for more info.`,
        },
        'announcement',
      ),
    );
  }
}

export interface TopbarAttrs {
  omnibox: m.Children;
}

export class Topbar implements m.ClassComponent<TopbarAttrs> {
  view({attrs}: m.Vnode<TopbarAttrs>) {
    const {omnibox} = attrs;
    return m(
      '.topbar',
      {class: globals.state.sidebarVisible ? '' : 'hide-sidebar'},
      omnibox,
      m(Progress),
      m(HelpPanningNotification),
      m(TraceErrorIcon),
    );
  }
}