using System;
using System.IO;
using System.Collections.Generic;
using System.Linq;
using Microsoft.DotNet.ProjectModel;
using Microsoft.DotNet.Cli.Utils;
using NuGet.Frameworks;

namespace Microsoft.DotNet.Tools.DependencyInvoker
{
    public class Program
    {
        public static int Main(string[] args)
        {
            DebugHelper.HandleDebugSwitch(ref args);

            var dotnetParams = new DotnetBaseParams("dotnet-dependency-tool-invoker", "DotNet Dependency Tool Invoker", "Invokes tools declared as NuGet dependencies of a project");
            
            dotnetParams.Parse(args);
            
            if (string.IsNullOrEmpty(dotnetParams.Command))
            {
                Console.WriteLine("A command name must be provided");
                
                return 1;
            }
            
            var projectContexts = 
                CreateProjectContexts(dotnetParams.ProjectPath)
                    .Where(p => dotnetParams.Framework == null ||
                                dotnetParams.Framework.GetShortFolderName()
                                .Equals(p.TargetFramework.GetShortFolderName()));
            
            var commandFactory =
                new ProjectDependenciesCommandFactory(
                    dotnetParams.Framework,
                    dotnetParams.Config,
                    dotnetParams.Output,
                    dotnetParams.BuildBasePath,
                    dotnetParams.ProjectPath);

            var result = 0;
            if(projectContexts.Any())
            {
                result = InvokeDependencyToolForProjectJson(projectContexts, commandFactory, dotnetParams);
            }
            else
            {
                result = InvokeDependencyToolForMSBuild(commandFactory, dotnetParams);
            }

            return result;
        }

        private static int InvokeDependencyToolForMSBuild(
            ProjectDependenciesCommandFactory commandFactory,
            DotnetBaseParams dotnetParams)
        {
            Console.WriteLine($"Invoking '{dotnetParams.Command}' for '{dotnetParams.Framework.GetShortFolderName()}'.");

            return InvokeDependencyTool(commandFactory, dotnetParams, dotnetParams.Framework);
        }

        private static int InvokeDependencyToolForProjectJson(
            IEnumerable<ProjectContext> projectContexts,
            ProjectDependenciesCommandFactory commandFactory,
            DotnetBaseParams dotnetParams)
        {
            foreach (var projectContext in projectContexts)
            {
                Console.WriteLine($"Invoking '{dotnetParams.Command}' for '{projectContext.TargetFramework}'.");

                if (InvokeDependencyTool(commandFactory, dotnetParams, projectContext.TargetFramework) != 0)
                {
                    return 1;
                }
            }

            return 0;
        }

        private static int InvokeDependencyTool(
            ProjectDependenciesCommandFactory commandFactory,
            DotnetBaseParams dotnetParams,
            NuGetFramework framework)
        {
            try
            {
                var exitCode = commandFactory.Create(
                        $"dotnet-{dotnetParams.Command}",
                        dotnetParams.RemainingArguments,
                        framework,
                        dotnetParams.Config)
                    .ForwardStdErr()
                    .ForwardStdOut()
                    .Execute()
                    .ExitCode;

                Console.WriteLine($"Command returned {exitCode}");
            }
            catch (CommandUnknownException)
            {
                Console.WriteLine($"Command not found");
                return 1;
            }

            return 0;
        }

        private static IEnumerable<ProjectContext> CreateProjectContexts(string projectPath = null)
        {
            projectPath = projectPath ?? Directory.GetCurrentDirectory();

            if (!projectPath.EndsWith(Project.FileName))
            {
                projectPath = Path.Combine(projectPath, Project.FileName);
            }

            if (!File.Exists(projectPath))
            {
                return Enumerable.Empty<ProjectContext>();
            }

            return ProjectContext.CreateContextForEachFramework(projectPath);
        }
    }
}