using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Drawing.Text;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
using Mesen.GUI.Config;
using Mesen.GUI.Forms;

namespace Mesen.GUI.Debugger
{
	public partial class frmDebugger : BaseForm
	{
		private List<Form> _childForms = new List<Form>();
		private InteropEmu.NotificationListener _notifListener;
		private ctrlDebuggerCode _lastCodeWindow;

		public frmDebugger()
		{
			InitializeComponent();
		}

		protected override void OnLoad(EventArgs e)
		{
 			base.OnLoad(e);

			this.mnuSplitView.Checked = ConfigManager.Config.DebugInfo.SplitView;
			this.mnuPpuPartialDraw.Checked = ConfigManager.Config.DebugInfo.PpuPartialDraw;

			_lastCodeWindow = ctrlDebuggerCode;

			this.ctrlDebuggerCode.SetConfig(ConfigManager.Config.DebugInfo.LeftView);
			this.ctrlDebuggerCodeSplit.SetConfig(ConfigManager.Config.DebugInfo.RightView);

			BreakpointManager.Breakpoints.Clear();
			BreakpointManager.Breakpoints.AddRange(ConfigManager.Config.DebugInfo.Breakpoints);
			BreakpointManager.BreakpointsChanged += BreakpointManager_BreakpointsChanged;
			this.ctrlBreakpoints.RefreshList();
			RefreshBreakpoints();

			this.toolTip.SetToolTip(this.picWatchHelp,
				"Most expressions/operators are accepted (C++ syntax)." + Environment.NewLine +
				"Note: Use the $ prefix to denote hexadecimal values." + Environment.NewLine + Environment.NewLine +
				"A/X/Y/PS/SP: Value of registers" + Environment.NewLine +
				"Irq/Nmi: True if the Irq/Nmi flags are set" + Environment.NewLine +
				"Cycle/Scanline: Current cycle (0-340)/scanline(-1 to 260) of the PPU" + Environment.NewLine +
				"Value: Current value being read/written from/to memory" + Environment.NewLine +
				"[<address>]: Value at address (CPU)" + Environment.NewLine + Environment.NewLine +

				"Examples:" + Environment.NewLine +
				"a == 10 || x == $23" + Environment.NewLine +
				"scanline == 10 && (cycle >= 55 && cycle <= 100)" + Environment.NewLine +
				"x == [$150] || y == [10]" + Environment.NewLine +
				"[[$15] + y]   -> Reads the value at address $15, adds Y to it and reads the value at the resulting address."
			);

			_notifListener = new InteropEmu.NotificationListener();
			_notifListener.OnNotification += _notifListener_OnNotification;

			InteropEmu.DebugInitialize();
			
			//Pause a few frames later to give the debugger a chance to disassemble some code
			InteropEmu.DebugStep(30000);

			UpdateCdlRatios();
			tmrCdlRatios.Start();
		}

		private void UpdateCdlRatios()
		{
			CdlRatios ratios = new CdlRatios();
			InteropEmu.DebugGetCdlRatios(ref ratios);

			lblPrgAnalysisResult.Text = string.Format("{0:0.00}% (Code: {1:0.00}%, Data: {2:0.00}%, Unknown: {3:0.00}%)", ratios.PrgRatio * 100, ratios.CodeRatio * 100, ratios.DataRatio * 100, (1 - ratios.PrgRatio) * 100);
			if(ratios.ChrRatio >= 0) {
				lblChrAnalysisResult.Text = string.Format("{0:0.00}% (Drawn: {1:0.00}%, Read: {2:0.00}%, Unknown: {3:0.00}%)", ratios.ChrRatio * 100, ratios.ChrDrawnRatio * 100, ratios.ChrReadRatio * 100, (1 - ratios.ChrRatio) * 100);
			} else {
				lblChrAnalysisResult.Text = "N/A (CHR RAM)";
			}
		}

		private void _notifListener_OnNotification(InteropEmu.NotificationEventArgs e)
		{
			switch(e.NotificationType) {
				case InteropEmu.ConsoleNotificationType.CodeBreak:
					this.BeginInvoke((MethodInvoker)(() => UpdateDebugger()));
					BreakpointManager.SetBreakpoints();
					InteropEmu.DebugSetFlags(mnuPpuPartialDraw.Checked ? DebuggerFlags.PpuPartialDraw : DebuggerFlags.None);
					break;

				case InteropEmu.ConsoleNotificationType.GameReset:
				case InteropEmu.ConsoleNotificationType.GameLoaded:
					BreakpointManager.SetBreakpoints();
					InteropEmu.DebugStep(1);
					break;
			}
		}

		private bool UpdateSplitView()
		{
			if(mnuSplitView.Checked) {
				tlpTop.ColumnStyles[1].SizeType = SizeType.Percent;
				tlpTop.ColumnStyles[0].Width = 50f;
				tlpTop.ColumnStyles[1].Width = 50f;
				this.MinimumSize = new Size(1250, 650);
			} else {
				tlpTop.ColumnStyles[1].SizeType = SizeType.Absolute;
				tlpTop.ColumnStyles[1].Width = 0f;
				this.MinimumSize = new Size(1000, 650);
			}
			ctrlDebuggerCodeSplit.Visible = mnuSplitView.Checked;
			return mnuSplitView.Checked;
		}

		private void UpdateDebugger()
		{
			if(InteropEmu.DebugIsCodeChanged()) {
				string code = System.Runtime.InteropServices.Marshal.PtrToStringAnsi(InteropEmu.DebugGetCode());
				ctrlDebuggerCode.Code = code;
				ctrlDebuggerCodeSplit.Code = code;
			}

			DebugState state = new DebugState();
			InteropEmu.DebugGetState(ref state);

			if(UpdateSplitView()) {
				ctrlDebuggerCodeSplit.UpdateCode(true);
			} else {
				_lastCodeWindow = ctrlDebuggerCode;
			}

			ctrlDebuggerCode.SelectActiveAddress(state.CPU.DebugPC);
			ctrlDebuggerCodeSplit.SetActiveAddress(state.CPU.DebugPC);
			RefreshBreakpoints();

			ctrlConsoleStatus.UpdateStatus(ref state);
			ctrlWatch.UpdateWatch();
			ctrlCallstack.UpdateCallstack();

			this.BringToFront();
		}

		private void ClearActiveStatement()
		{
			ctrlDebuggerCode.ClearActiveAddress();
			ctrlDebuggerCodeSplit.ClearActiveAddress();
			RefreshBreakpoints();
		}

		private void ToggleBreakpoint(bool toggleEnabled)
		{
			BreakpointManager.ToggleBreakpoint(_lastCodeWindow.GetCurrentLine(), toggleEnabled);
		}
		
		private void RefreshBreakpoints()
		{
			ConfigManager.Config.DebugInfo.Breakpoints = new List<Breakpoint>(BreakpointManager.Breakpoints);
			ConfigManager.ApplyChanges();

			ctrlDebuggerCodeSplit.HighlightBreakpoints();
			ctrlDebuggerCode.HighlightBreakpoints();
		}

		private void OpenChildForm(Form frm)
		{
			this._childForms.Add(frm);
			frm.FormClosed += (obj, args) => {
				this._childForms.Remove((Form)obj);
			};
			frm.Show();
		}

		private void mnuContinue_Click(object sender, EventArgs e)
		{
			ClearActiveStatement();
			InteropEmu.DebugRun();
		}

		private void frmDebugger_FormClosed(object sender, FormClosedEventArgs e)
		{
			InteropEmu.DebugRelease();
		}

		private void mnuToggleBreakpoint_Click(object sender, EventArgs e)
		{
			ToggleBreakpoint(false);
		}

		private void mnuDisableEnableBreakpoint_Click(object sender, EventArgs e)
		{
			ToggleBreakpoint(true);
		}

		private void mnuBreak_Click(object sender, EventArgs e)
		{
			InteropEmu.DebugStep(1);
		}

		private void mnuStepInto_Click(object sender, EventArgs e)
		{
			InteropEmu.DebugStep(1);
		}

		private void mnuStepOut_Click(object sender, EventArgs e)
		{
			InteropEmu.DebugStepOut();
		}
		
		private void mnuStepOver_Click(object sender, EventArgs e)
		{
			InteropEmu.DebugStepOver();
		}


		private void mnuRunPpuCycle_Click(object sender, EventArgs e)
		{
			InteropEmu.DebugPpuStep(1);
		}

		private void mnuRunScanline_Click(object sender, EventArgs e)
		{
			InteropEmu.DebugPpuStep(341);
		}

		private void mnuRunOneFrame_Click(object sender, EventArgs e)
		{
			InteropEmu.DebugPpuStep(89341);
		}

		private void ctrlDebuggerCode_OnWatchAdded(AddressEventArgs args)
		{
			this.ctrlWatch.AddWatch(args.Address);
		}

		private void ctrlDebuggerCode_OnSetNextStatement(AddressEventArgs args)
		{
			UInt16 addr = (UInt16)args.Address;
			InteropEmu.DebugSetNextStatement(addr);
			this.UpdateDebugger();
		}

		private void mnuFind_Click(object sender, EventArgs e)
		{
			_lastCodeWindow.OpenSearchBox();
		}
		
		private void mnuFindNext_Click(object sender, EventArgs e)
		{
			_lastCodeWindow.FindNext();
		}

		private void mnuFindPrev_Click(object sender, EventArgs e)
		{
			_lastCodeWindow.FindPrevious();
		}

		private void mnuSplitView_Click(object sender, EventArgs e)
		{
			ConfigManager.Config.DebugInfo.SplitView = this.mnuSplitView.Checked;
			ConfigManager.ApplyChanges();

			UpdateDebugger();
		}

		private void mnuMemoryViewer_Click(object sender, EventArgs e)
		{
			OpenChildForm(new frmMemoryViewer());
		}

		private void BreakpointManager_BreakpointsChanged(object sender, EventArgs e)
		{
			RefreshBreakpoints();
		}

		private void ctrlDebuggerCode_Enter(object sender, EventArgs e)
		{
			_lastCodeWindow = ctrlDebuggerCode;
		}

		private void ctrlDebuggerCodeSplit_Enter(object sender, EventArgs e)
		{
			_lastCodeWindow = ctrlDebuggerCodeSplit;
		}

		private void mnuGoToAddress_Click(object sender, EventArgs e)
		{
			_lastCodeWindow.GoToAddress();
		}

		private void mnuGoToIrqHandler_Click(object sender, EventArgs e)
		{
			int address = (InteropEmu.DebugGetMemoryValue(0xFFFF) << 8) | InteropEmu.DebugGetMemoryValue(0xFFFE);
			_lastCodeWindow.ScrollToLineNumber(address);
		}

		private void mnuGoToNmiHandler_Click(object sender, EventArgs e)
		{
			int address = (InteropEmu.DebugGetMemoryValue(0xFFFB) << 8) | InteropEmu.DebugGetMemoryValue(0xFFFA);
			_lastCodeWindow.ScrollToLineNumber(address);
		}

		private void mnuGoToResetHandler_Click(object sender, EventArgs e)
		{
			int address = (InteropEmu.DebugGetMemoryValue(0xFFFD) << 8) | InteropEmu.DebugGetMemoryValue(0xFFFC);
			_lastCodeWindow.ScrollToLineNumber(address);
		}

		private void mnuIncreaseFontSize_Click(object sender, EventArgs e)
		{
			_lastCodeWindow.FontSize++;
		}

		private void mnuDecreaseFontSize_Click(object sender, EventArgs e)
		{
			_lastCodeWindow.FontSize--;
		}

		private void mnuResetFontSize_Click(object sender, EventArgs e)
		{
			_lastCodeWindow.FontSize = 13;
		}

		private void mnuClose_Click(object sender, EventArgs e)
		{
			this.Close();
		}

		protected override void OnFormClosed(FormClosedEventArgs e)
		{
			foreach(Form frm in this._childForms.ToArray()) {
				frm.Close();
			}
			base.OnFormClosed(e);
		}

		private void mnuNametableViewer_Click(object sender, EventArgs e)
		{
			OpenChildForm(new frmPpuViewer());
		}

		private void ctrlCallstack_FunctionSelected(object sender, EventArgs e)
		{
			_lastCodeWindow.ScrollToLineNumber((int)sender);
		}

		private void tmrCdlRatios_Tick(object sender, EventArgs e)
		{
			this.UpdateCdlRatios();
		}

		private void mnuLoadCdlFile_Click(object sender, EventArgs e)
		{
			OpenFileDialog ofd = new OpenFileDialog();
			ofd.Filter = "CDL files (*.cdl)|*.cdl";
			if(ofd.ShowDialog() == System.Windows.Forms.DialogResult.OK) {
				if(!InteropEmu.DebugLoadCdlFile(ofd.FileName)) {
					MessageBox.Show("Could not load CDL file.  The file selected file is invalid.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
				}
			}
		}

		private void mnuSaveAsCdlFile_Click(object sender, EventArgs e)
		{
			SaveFileDialog sfd = new SaveFileDialog();
			sfd.Filter = "CDL files (*.cdl)|*.cdl";
			sfd.AddExtension = true;
			if(sfd.ShowDialog() == System.Windows.Forms.DialogResult.OK) {
				if(!InteropEmu.DebugSaveCdlFile(sfd.FileName)) {
					MessageBox.Show("Error while trying to save CDL file.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
				}
			}
		}

		private void mnuResetCdlLog_Click(object sender, EventArgs e)
		{
			InteropEmu.DebugResetCdlLog();
		}

		private void ctrlBreakpoints_BreakpointNavigation(object sender, EventArgs e)
		{
			_lastCodeWindow.ScrollToLineNumber((int)((Breakpoint)sender).Address);
		}

		private void mnuTraceLogger_Click(object sender, EventArgs e)
		{
			new frmTraceLogger().Show();
		}

		private void mnuPpuPartialDraw_Click(object sender, EventArgs e)
		{
			ConfigManager.Config.DebugInfo.PpuPartialDraw = mnuPpuPartialDraw.Checked;
			ConfigManager.ApplyChanges();
		}
	}
}