using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.CompilerServices;
using Editor;
using Sandbox;

namespace SboxMcpServer;

public class McpServerWindow : Widget
{
	/// <summary>Resolves a path relative to the library root using the source file location at compile time.</summary>
	private static string GetAssetPath( string folder, string file, [CallerFilePath] string sourceFile = "" )
	{
		var libRoot = Path.GetFullPath( Path.Combine( Path.GetDirectoryName( sourceFile ), ".." ) );
		return Path.Combine( libRoot, folder, file );
	}

	private Label _statusLabel;
	private Label _portLabel;
	private Label _sessionCountLabel;
	private Button _toggleButton;
	private Widget _logCanvas;
	private ToggleSwitch _autoStartToggle;

	private static readonly List<string> _logEntries = new();
	private const int MaxLogEntries = 200;

	[ConVar( "mcp_server_autostart", ConVarFlags.Saved )]
	public static bool AutoStart { get; set; } = true;

	// Open via the Editor menu
	[Menu( "Editor", "MCP/Open MCP Panel" )]
	public static void OpenPanel()
	{
		var win = new McpServerWindow();
		win.Show();
	}

	// Static constructor runs once when the library assembly is loaded by the editor.
	static McpServerWindow()
	{
		if ( AutoStart && !McpServer.IsRunning )
		{
			McpServer.StartServer();
		}
	}

	public McpServerWindow() : base( null )
	{
		WindowTitle = "MCP Server";
		MinimumSize = new Vector2( 500, 400 );

		McpServer.OnServerStateChanged += OnStateChanged;
		McpServer.OnLogMessage += OnLogMessage;

		BuildUI();
		OnStateChanged();
	}

	public override void OnDestroyed()
	{
		McpServer.OnServerStateChanged -= OnStateChanged;
		McpServer.OnLogMessage -= OnLogMessage;
		base.OnDestroyed();
	}

	private void BuildUI()
	{
		var root = Layout.Column();
		root.Margin = 8;
		root.Spacing = 6;

		// ── Logo Header ────────────────────────────────────────────────
		var logo = new Widget();
		try
		{
			// Resolve the logo path from the source file location (Assembly.Location is null in S&box)
			var logoPath = GetAssetPath( "Image", "Logo.jpg" ).Replace( '\\', '/' );
			logo.SetStyles( $"background-image: url('{logoPath}'); background-position: center; background-repeat: no-repeat; min-height: 80px; margin-bottom: 8px;" );
		}
		catch { }
		root.Add( logo );

		// ── Status Row ─────────────────────────────────────────────────
		var statusRow = Layout.Row();
		statusRow.Spacing = 16;

		var statusCol = Layout.Column();
		var statusTitle = new Label( "STATUS" );
		statusTitle.SetStyles( "font-size: 10px; color: #888;" );
		statusCol.Add( statusTitle );
		_statusLabel = new Label( "● Stopped" );
		_statusLabel.SetStyles( "font-size: 15px; font-weight: bold; color: #f87171;" );
		statusCol.Add( _statusLabel );
		statusRow.Add( statusCol );

		var portCol = Layout.Column();
		var portTitle = new Label( "PORT" );
		portTitle.SetStyles( "font-size: 10px; color: #888;" );
		portCol.Add( portTitle );
		_portLabel = new Label( McpServer.Port.ToString() );
		_portLabel.SetStyles( "font-size: 15px; font-weight: bold;" );
		portCol.Add( _portLabel );
		statusRow.Add( portCol );

		var sessionCol = Layout.Column();
		var sessionTitle = new Label( "SESSIONS" );
		sessionTitle.SetStyles( "font-size: 10px; color: #888;" );
		sessionCol.Add( sessionTitle );
		_sessionCountLabel = new Label( "0" );
		_sessionCountLabel.SetStyles( "font-size: 15px; font-weight: bold;" );
		sessionCol.Add( _sessionCountLabel );
		statusRow.Add( sessionCol );

		statusRow.AddStretchCell();

		_toggleButton = new Button( "Start MCP Server", "play_arrow" );
		_toggleButton.Clicked += ToggleServer;
		statusRow.Add( _toggleButton );

		root.Add( statusRow );

		// ── Auto-start Row ─────────────────────────────────────────────
		var autoRow = Layout.Row();
		autoRow.Spacing = 8;
		_autoStartToggle = new ToggleSwitch( "Auto-start MCP Server on editor load" );
		_autoStartToggle.Value = AutoStart;
		_autoStartToggle.ToolTip = $"mcp_server_autostart (default: true). Change takes effect on next editor launch.";
		_autoStartToggle.MouseClick += () =>
		{
			AutoStart = _autoStartToggle.Value;
		};
		autoRow.Add( _autoStartToggle );
		root.Add( autoRow );
		root.AddSeparator();

		// ── Log Header ─────────────────────────────────────────────────
		var logHeader = Layout.Row();
		var logTitle = new Label( "Activity Log" );
		logTitle.SetStyles( "font-weight: bold; font-size: 13px;" );
		logHeader.Add( logTitle );
		logHeader.AddStretchCell();

		var clearBtn = new Button( "", "delete_sweep" );
		clearBtn.ToolTip = "Clear Log";
		clearBtn.FixedWidth = 26;
		clearBtn.FixedHeight = 26;
		clearBtn.Clicked += () => { _logEntries.Clear(); _logCanvas.DestroyChildren(); };
		logHeader.Add( clearBtn );
		root.Add( logHeader );

		// ── Log Area ───────────────────────────────────────────────────
		var scroll = new ScrollArea( null );
		scroll.MinimumHeight = 250;

		_logCanvas = new Widget();
		_logCanvas.Layout = Layout.Column();
		scroll.Canvas = _logCanvas;

		foreach ( var entry in _logEntries )
		{
			AddLogLabel( entry );
		}

		root.Add( scroll, 1 );

		Layout = root;
	}

	private void AddLogLabel( string text )
	{
		var lbl = new Label( text );
		lbl.WordWrap = true;
		
		string color = "#e5e7eb";
		string weight = "normal";

		if ( text.Contains( "[ERROR]" ) )
		{
			color = "#f87171";
			weight = "bold";
		}
		else if ( text.Contains( "] Tool: " ) )
		{
			color = "#60a5fa";
			weight = "bold";
		}
		else if ( text.Contains( "Started" ) || text.Contains( "Created new MCP" ) || text.Contains( "initialized" ) )
		{
			color = "#4ade80";
		}
		else if ( text.Contains( "] Waiting for" ) || text.Contains( "] Resumed on" ) || text.Contains( "Closed MCP" ) || text.Contains( "Stopped" ) )
		{
			color = "#9ca3af";
		}

		lbl.SetStyles( $"font-family: monospace; font-size: 11px; padding: 2px; color: {color}; font-weight: {weight};" );
		_logCanvas.Layout.Add( lbl );
	}

	private void ToggleServer()
	{
		if ( McpServer.IsRunning )
			McpServer.StopServer();
		else
			McpServer.StartServer();
	}

	private void OnStateChanged()
	{
		if ( !IsValid ) return;

		_portLabel.Text = McpServer.Port.ToString();
		_sessionCountLabel.Text = McpServer.SessionCount.ToString();

		if ( McpServer.IsRunning )
		{
			_statusLabel.Text = "● Running";
			_statusLabel.SetStyles( "font-size: 15px; font-weight: bold; color: #4ade80;" );
			_toggleButton.Text = "Stop MCP Server";
		}
		else
		{
			_statusLabel.Text = "● Stopped";
			_statusLabel.SetStyles( "font-size: 15px; font-weight: bold; color: #f87171;" );
			_toggleButton.Text = "Start MCP Server";
		}
	}

	private void OnLogMessage( string message )
	{
		if ( !IsValid ) return;

		var text = $"[{DateTime.Now:HH:mm:ss}] {message}";
		_logEntries.Add( text );

		AddLogLabel( text );

		if ( _logEntries.Count > MaxLogEntries )
		{
			_logEntries.RemoveAt( 0 );
			
			var firstChild = _logCanvas.Children.FirstOrDefault();
			firstChild?.Destroy();
		}
	}
}