// Copyright (c) .NET Foundation. All rights reserved.
// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using Microsoft.Build.Framework;
using Microsoft.Build.Utilities;
using RepoTasks.ProjectModel;
using RepoTasks.Utilities;

namespace RepoTasks
{
    public class AnalyzeBuildGraph : Task, ICancelableTask
    {
        private readonly CancellationTokenSource _cts = new CancellationTokenSource();

        /// <summary>
        /// Repositories that we are building new versions of.
        /// </summary>
        [Required]
        public ITaskItem[] Solutions { get; set; }

        [Required]
        public string Properties { get; set; }

        /// <summary>
        /// New packages we are compiling. Used in the pin tool.
        /// </summary>
        [Output]
        public ITaskItem[] PackagesProduced { get; set; }

        /// <summary>
        /// The order in which to build repositories
        /// </summary>
        [Output]
        public ITaskItem[] RepositoryBuildOrder { get; set; }

        public void Cancel()
        {
            _cts.Cancel();
        }

        public override bool Execute()
        {
            var factory = new SolutionInfoFactory(Log, BuildEngine5);
            var props = MSBuildListSplitter.GetNamedProperties(Properties);

            Log.LogMessage(MessageImportance.High, $"Beginning cross-repo analysis on {Solutions.Length} solutions. Hang tight...");

            var solutions = factory.Create(Solutions, props, _cts.Token);
            Log.LogMessage($"Found {solutions.Count} and {solutions.Sum(p => p.Projects.Count)} projects");

            if (_cts.IsCancellationRequested)
            {
                return false;
            }

            PackagesProduced = solutions
                .Where(s => s.ShouldBuild)
                .SelectMany(p => p.Projects)
                .Where(p => p.IsPackable)
                .Select(p => new TaskItem(p.PackageId, new Hashtable
                {
                    ["Version"] = p.PackageVersion
                }))
                .ToArray();

            return !Log.HasLoggedErrors;
        }
    }
}