// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

#nullable disable

using Microsoft.DotNet.Cli.Utils;
using Microsoft.DotNet.Cli.Utils.Extensions;
using NuGet.Frameworks;
using NuGet.ProjectModel;

namespace Microsoft.DotNet.Cli.CommandFactory.CommandResolution;

public class ProjectDependenciesCommandResolver : ICommandResolver
{
    private const string ProjectDependenciesCommandResolverName = "projectdependenciescommandresolver";

    private readonly IEnvironmentProvider _environment;
    private readonly IPackagedCommandSpecFactory _packagedCommandSpecFactory;

    public ProjectDependenciesCommandResolver(
        IEnvironmentProvider environment,
        IPackagedCommandSpecFactory packagedCommandSpecFactory)
    {
        if (environment == null)
        {
            throw new ArgumentNullException(nameof(environment));
        }

        if (packagedCommandSpecFactory == null)
        {
            throw new ArgumentNullException(nameof(packagedCommandSpecFactory));
        }

        _environment = environment;
        _packagedCommandSpecFactory = packagedCommandSpecFactory;
    }

    public CommandSpec Resolve(CommandResolverArguments commandResolverArguments)
    {
        Reporter.Verbose.WriteLine(string.Format(
            CliStrings.AttemptingToResolve,
            ProjectDependenciesCommandResolverName,
            commandResolverArguments.CommandName));

        if (commandResolverArguments.Framework == null
            || commandResolverArguments.ProjectDirectory == null
            || commandResolverArguments.Configuration == null
            || commandResolverArguments.CommandName == null)
        {
            Reporter.Verbose.WriteLine(string.Format(
                CliStrings.InvalidCommandResolverArguments,
                ProjectDependenciesCommandResolverName));

            return null;
        }

        return ResolveFromProjectDependencies(
                commandResolverArguments.ProjectDirectory,
                commandResolverArguments.Framework,
                commandResolverArguments.Configuration,
                commandResolverArguments.CommandName,
                commandResolverArguments.CommandArguments.OrEmptyIfNull(),
                commandResolverArguments.OutputPath,
                commandResolverArguments.BuildBasePath);
    }

    private CommandSpec ResolveFromProjectDependencies(
        string projectDirectory,
        NuGetFramework framework,
        string configuration,
        string commandName,
        IEnumerable<string> commandArguments,
        string outputPath,
        string buildBasePath)
    {
        var allowedExtensions = GetAllowedCommandExtensionsFromEnvironment(_environment);

        var projectFactory = new ProjectFactory(_environment);
        var project = projectFactory.GetProject(
            projectDirectory,
            framework,
            configuration,
            buildBasePath,
            outputPath);

        if (project == null)
        {
            Reporter.Verbose.WriteLine(string.Format(
                CliStrings.DidNotFindAMatchingProject,
                ProjectDependenciesCommandResolverName,
                projectDirectory));
            return null;
        }

        var depsFilePath = project.DepsJsonPath;

        if (!File.Exists(depsFilePath))
        {
            Reporter.Verbose.WriteLine(string.Format(
                CliStrings.DoesNotExist,
                ProjectDependenciesCommandResolverName,
                depsFilePath));
            return null;
        }

        var runtimeConfigPath = project.RuntimeConfigJsonPath;

        if (!File.Exists(runtimeConfigPath))
        {
            Reporter.Verbose.WriteLine(string.Format(
                CliStrings.DoesNotExist,
                ProjectDependenciesCommandResolverName,
                runtimeConfigPath));
            return null;
        }

        var lockFile = project.GetLockFile();
        var toolLibrary = GetToolLibraryForContext(lockFile, commandName, framework);

        var commandSpec = _packagedCommandSpecFactory.CreateCommandSpecFromLibrary(
                    toolLibrary,
                    commandName,
                    commandArguments,
                    allowedExtensions,
                    lockFile,
                    depsFilePath,
                    runtimeConfigPath);

        commandSpec?.AddEnvironmentVariablesFromProject(project);

        return commandSpec;
    }

    private static LockFileTargetLibrary GetToolLibraryForContext(
        LockFile lockFile, string commandName, NuGetFramework targetFramework)
    {
        var toolLibraries = lockFile.Targets
            .FirstOrDefault(t => t.TargetFramework.GetShortFolderName()
                                  .Equals(targetFramework.GetShortFolderName()))
            ?.Libraries.Where(l => l.Name == commandName ||
                l.RuntimeAssemblies.Any(r => Path.GetFileNameWithoutExtension(r.Path) == commandName)).ToList();

        if (toolLibraries?.Count() > 1)
        {
            throw new InvalidOperationException(string.Format(
                CliStrings.AmbiguousCommandName,
                commandName));
        }

        Reporter.Verbose.WriteLine(string.Format(
            CliStrings.ToolLibraryFound,
            ProjectDependenciesCommandResolverName,
            toolLibraries?.Count() > 0));

        return toolLibraries?.FirstOrDefault();
    }

    private static IEnumerable<string> GetAllowedCommandExtensionsFromEnvironment(IEnvironmentProvider environment)
    {
        var allowedCommandExtensions = new List<string>();
        allowedCommandExtensions.AddRange(environment.ExecutableExtensions);
        allowedCommandExtensions.Add(FileNameSuffixes.DotNet.DynamicLib);

        return allowedCommandExtensions;
    }
}