// Copyright (C) 2020 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 {exists} from '../../base/utils';
import {ColumnDef, Sorting, ThreadStateExtra} from '../../public/aggregation';
import {AreaSelection} from '../../public/selection';
import {THREAD_STATE_TRACK_KIND} from '../../public/track_kinds';
import {Engine} from '../../trace_processor/engine';
import {NUM, NUM_NULL, STR_NULL} from '../../trace_processor/query_result';
import {AreaSelectionAggregator} from '../../public/selection';
import {translateState} from '../../components/sql_utils/thread_state';
import {TrackDescriptor} from '../../public/track';

export class ThreadStateSelectionAggregator implements AreaSelectionAggregator {
  readonly id = 'thread_state_aggregation';
  private utids?: number[];

  setThreadStateUtids(tracks: ReadonlyArray<TrackDescriptor>) {
    this.utids = [];
    for (const trackInfo of tracks) {
      if (trackInfo?.tags?.kind === THREAD_STATE_TRACK_KIND) {
        exists(trackInfo.tags.utid) && this.utids.push(trackInfo.tags.utid);
      }
    }
  }

  async createAggregateView(engine: Engine, area: AreaSelection) {
    this.setThreadStateUtids(area.tracks);
    if (this.utids === undefined || this.utids.length === 0) return false;

    await engine.query(`
      create or replace perfetto table ${this.id} as
      select
        process.name as process_name,
        process.pid,
        thread.name as thread_name,
        thread.tid,
        tstate.state || ',' || ifnull(tstate.io_wait, 'NULL') as concat_state,
        sum(tstate.dur) AS total_dur,
        sum(tstate.dur) / count() as avg_dur,
        count() as occurrences
      from thread_state tstate
      join thread using (utid)
      left join process using (upid)
      where
        utid in (${this.utids})
        and ts + dur > ${area.start}
        and ts < ${area.end}
      group by utid, concat_state
    `);
    return true;
  }

  async getExtra(
    engine: Engine,
    area: AreaSelection,
  ): Promise<ThreadStateExtra | void> {
    this.setThreadStateUtids(area.tracks);
    if (this.utids === undefined || this.utids.length === 0) return;

    const query = `
      select
        state,
        io_wait as ioWait,
        sum(dur) as totalDur
      from thread
      join thread_state using (utid)
      where utid in (${this.utids})
        and thread_state.ts + thread_state.dur > ${area.start}
        and thread_state.ts < ${area.end}
      group by state, io_wait
    `;
    const result = await engine.query(query);

    const it = result.iter({
      state: STR_NULL,
      ioWait: NUM_NULL,
      totalDur: NUM,
    });

    let totalMs = 0;
    const values = new Float64Array(result.numRows());
    const states = [];
    for (let i = 0; it.valid(); ++i, it.next()) {
      const state = it.state == null ? undefined : it.state;
      const ioWait = it.ioWait === null ? undefined : it.ioWait > 0;
      states.push(translateState(state, ioWait));
      const ms = it.totalDur / 1000000;
      values[i] = ms;
      totalMs += ms;
    }
    return {
      kind: 'THREAD_STATE',
      states,
      values,
      totalMs,
    };
  }

  getColumnDefinitions(): ColumnDef[] {
    return [
      {
        title: 'Process',
        kind: 'STRING',
        columnConstructor: Uint16Array,
        columnId: 'process_name',
      },
      {
        title: 'PID',
        kind: 'NUMBER',
        columnConstructor: Uint16Array,
        columnId: 'pid',
      },
      {
        title: 'Thread',
        kind: 'STRING',
        columnConstructor: Uint16Array,
        columnId: 'thread_name',
      },
      {
        title: 'TID',
        kind: 'NUMBER',
        columnConstructor: Uint16Array,
        columnId: 'tid',
      },
      {
        title: 'State',
        kind: 'STATE',
        columnConstructor: Uint16Array,
        columnId: 'concat_state',
      },
      {
        title: 'Wall duration (ms)',
        kind: 'TIMESTAMP_NS',
        columnConstructor: Float64Array,
        columnId: 'total_dur',
        sum: true,
      },
      {
        title: 'Avg Wall duration (ms)',
        kind: 'TIMESTAMP_NS',
        columnConstructor: Float64Array,
        columnId: 'avg_dur',
      },
      {
        title: 'Occurrences',
        kind: 'NUMBER',
        columnConstructor: Uint16Array,
        columnId: 'occurrences',
        sum: true,
      },
    ];
  }

  getTabName() {
    return 'Thread States';
  }

  getDefaultSorting(): Sorting {
    return {column: 'total_dur', direction: 'DESC'};
  }
}