"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.createTestGroups = createTestGroups;
exports.filterForShard = filterForShard;
/**
 * Copyright Microsoft Corporation. All rights reserved.
 *
 * 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 createTestGroups(projectSuite, expectedParallelism) {
  // This function groups tests that can be run together.
  // Tests cannot be run together when:
  // - They belong to different projects - requires different workers.
  // - They have a different repeatEachIndex - requires different workers.
  // - They have a different set of worker fixtures in the pool - requires different workers.
  // - They have a different requireFile - reuses the worker, but runs each requireFile separately.
  // - They belong to a parallel suite.

  // Using the map "workerHash -> requireFile -> group" makes us preserve the natural order
  // of worker hashes and require files for the simple cases.
  const groups = new Map();
  const createGroup = test => {
    return {
      workerHash: test._workerHash,
      requireFile: test._requireFile,
      repeatEachIndex: test.repeatEachIndex,
      projectId: test._projectId,
      tests: []
    };
  };
  for (const test of projectSuite.allTests()) {
    let withWorkerHash = groups.get(test._workerHash);
    if (!withWorkerHash) {
      withWorkerHash = new Map();
      groups.set(test._workerHash, withWorkerHash);
    }
    let withRequireFile = withWorkerHash.get(test._requireFile);
    if (!withRequireFile) {
      withRequireFile = {
        general: createGroup(test),
        parallel: new Map(),
        parallelWithHooks: createGroup(test)
      };
      withWorkerHash.set(test._requireFile, withRequireFile);
    }

    // Note that a parallel suite cannot be inside a serial suite. This is enforced in TestType.
    let insideParallel = false;
    let outerMostSequentialSuite;
    let hasAllHooks = false;
    for (let parent = test.parent; parent; parent = parent.parent) {
      if (parent._parallelMode === 'serial' || parent._parallelMode === 'default') outerMostSequentialSuite = parent;
      insideParallel = insideParallel || parent._parallelMode === 'parallel';
      hasAllHooks = hasAllHooks || parent._hooks.some(hook => hook.type === 'beforeAll' || hook.type === 'afterAll');
    }
    if (insideParallel) {
      if (hasAllHooks && !outerMostSequentialSuite) {
        withRequireFile.parallelWithHooks.tests.push(test);
      } else {
        const key = outerMostSequentialSuite || test;
        let group = withRequireFile.parallel.get(key);
        if (!group) {
          group = createGroup(test);
          withRequireFile.parallel.set(key, group);
        }
        group.tests.push(test);
      }
    } else {
      withRequireFile.general.tests.push(test);
    }
  }
  const result = [];
  for (const withWorkerHash of groups.values()) {
    for (const withRequireFile of withWorkerHash.values()) {
      // Tests without parallel mode should run serially as a single group.
      if (withRequireFile.general.tests.length) result.push(withRequireFile.general);

      // Parallel test groups without beforeAll/afterAll can be run independently.
      result.push(...withRequireFile.parallel.values());

      // Tests with beforeAll/afterAll should try to share workers as much as possible.
      const parallelWithHooksGroupSize = Math.ceil(withRequireFile.parallelWithHooks.tests.length / expectedParallelism);
      let lastGroup;
      for (const test of withRequireFile.parallelWithHooks.tests) {
        if (!lastGroup || lastGroup.tests.length >= parallelWithHooksGroupSize) {
          lastGroup = createGroup(test);
          result.push(lastGroup);
        }
        lastGroup.tests.push(test);
      }
    }
  }
  return result;
}
function filterForShard(shard, testGroups) {
  // Note that sharding works based on test groups.
  // This means parallel files will be sharded by single tests,
  // while non-parallel files will be sharded by the whole file.
  //
  // Shards are still balanced by the number of tests, not files,
  // even in the case of non-paralleled files.

  let shardableTotal = 0;
  for (const group of testGroups) shardableTotal += group.tests.length;

  // Each shard gets some tests.
  const shardSize = Math.floor(shardableTotal / shard.total);
  // First few shards get one more test each.
  const extraOne = shardableTotal - shardSize * shard.total;
  const currentShard = shard.current - 1; // Make it zero-based for calculations.
  const from = shardSize * currentShard + Math.min(extraOne, currentShard);
  const to = from + shardSize + (currentShard < extraOne ? 1 : 0);
  let current = 0;
  const result = new Set();
  for (const group of testGroups) {
    // Any test group goes to the shard that contains the first test of this group.
    // So, this shard gets any group that starts at [from; to)
    if (current >= from && current < to) result.add(group);
    current += group.tests.length;
  }
  return result;
}