// Copyright (C) 2024 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 {TrackContext} from '../public/track';
import {
  CustomSqlTableDefConfig,
  CustomSqlTableSliceTrack,
} from './tracks/custom_sql_table_slice_track';
import {
  SliceColumns,
  SqlDataSource,
} from '../public/lib/debug_tracks/debug_tracks';
import {uuidv4Sql} from '../base/uuid';
import {
  ARG_PREFIX,
  DebugSliceDetailsPanel,
} from '../public/lib/debug_tracks/details_tab';
import {createPerfettoTable} from '../trace_processor/sql_utils';
import {Trace} from '../public/trace';
import {TrackEventSelection} from '../public/selection';

export interface SimpleSliceTrackConfig {
  data: SqlDataSource;
  columns: SliceColumns;
  argColumns: string[];
}

export class SimpleSliceTrack extends CustomSqlTableSliceTrack {
  private config: SimpleSliceTrackConfig;
  public readonly sqlTableName: string;

  constructor(trace: Trace, ctx: TrackContext, config: SimpleSliceTrackConfig) {
    super({
      trace,
      uri: ctx.trackUri,
    });

    this.config = config;
    this.sqlTableName = `__simple_slice_${uuidv4Sql(ctx.trackUri)}`;
  }

  async getSqlDataSource(): Promise<CustomSqlTableDefConfig> {
    const table = await createPerfettoTable(
      this.engine,
      this.sqlTableName,
      this.createTableQuery(
        this.config.data,
        this.config.columns,
        this.config.argColumns,
      ),
    );
    return {
      sqlTableName: this.sqlTableName,
      disposable: table,
    };
  }

  private createTableQuery(
    data: SqlDataSource,
    sliceColumns: SliceColumns,
    argColumns: string[],
  ): string {
    // If the view has clashing names (e.g. "name" coming from joining two
    // different tables, we will see names like "name_1", "name_2", but they
    // won't be addressable from the SQL. So we explicitly name them through a
    // list of columns passed to CTE.
    const dataColumns =
      data.columns !== undefined ? `(${data.columns.join(', ')})` : '';

    // TODO(altimin): Support removing this table when the track is closed.
    const dur = sliceColumns.dur === '0' ? 0 : sliceColumns.dur;
    return `
      with data${dataColumns} as (
        ${data.sqlSource}
      ),
      prepared_data as (
        select
          ${sliceColumns.ts} as ts,
          ifnull(cast(${dur} as int), -1) as dur,
          printf('%s', ${sliceColumns.name}) as name
          ${argColumns.length > 0 ? ',' : ''}
          ${argColumns.map((c) => `${c} as ${ARG_PREFIX}${c}`).join(',\n')}
        from data
      )
      select
        row_number() over (order by ts) as id,
        *
      from prepared_data
      order by ts
    `;
  }

  override detailsPanel({eventId}: TrackEventSelection) {
    return new DebugSliceDetailsPanel(this.trace, this.sqlTableName, eventId);
  }
}