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

namespace Mesen.GUI.Debugger
{
	public partial class frmTraceLogger : BaseForm
	{
		private int _lineCount;
		private bool _loggingEnabled = false;
		private string _lastFilename;
		private EntityBinder _entityBinder = new EntityBinder();
		private int _previousCycleCount;
		private string _previousTrace;
		private volatile bool _refreshRunning;
		private bool _initialized;

		public frmTraceLogger()
		{
			InitializeComponent();

			DebugInfo debugInfo = ConfigManager.Config.DebugInfo;
			if(!debugInfo.TraceLoggerSize.IsEmpty) {
				this.StartPosition = FormStartPosition.Manual;
				this.Size = debugInfo.TraceLoggerSize;
				this.Location = debugInfo.TraceLoggerLocation;
			}

			txtTraceLog.BaseFont = new Font(debugInfo.TraceFontFamily, debugInfo.TraceFontSize, debugInfo.TraceFontStyle);
			txtTraceLog.TextZoom = debugInfo.TraceTextZoom;

			mnuAutoRefresh.Checked = debugInfo.TraceAutoRefresh;
			_lineCount = debugInfo.TraceLineCount;

			_entityBinder.Entity = debugInfo.TraceLoggerOptions;
			_entityBinder.AddBinding("ShowByteCode", chkShowByteCode);
			_entityBinder.AddBinding("ShowCpuCycles", chkShowCpuCycles);
			_entityBinder.AddBinding("ShowEffectiveAddresses", chkShowEffectiveAddresses);
			_entityBinder.AddBinding("ShowMemoryValues", chkShowMemoryValues);
			_entityBinder.AddBinding("ShowExtraInfo", chkShowExtraInfo);
			_entityBinder.AddBinding("ShowPpuFrames", chkShowFrameCount);
			_entityBinder.AddBinding("ShowPpuCycles", chkShowPpuCycles);
			_entityBinder.AddBinding("ShowPpuScanline", chkShowPpuScanline);
			_entityBinder.AddBinding("ShowRegisters", chkShowRegisters);
			_entityBinder.AddBinding("IndentCode", chkIndentCode);
			_entityBinder.AddBinding("UseLabels", chkUseLabels);
			_entityBinder.AddBinding("ExtendZeroPage", chkExtendZeroPage);
			_entityBinder.AddBinding("UseWindowsEol", chkUseWindowsEol);
			_entityBinder.AddBinding("StatusFormat", cboStatusFlagFormat);
			_entityBinder.AddBinding("OverrideFormat", chkOverrideFormat);
			_entityBinder.UpdateUI();

			this.toolTip.SetToolTip(this.picExpressionWarning, "Condition contains invalid syntax or symbols.");
			this.toolTip.SetToolTip(this.picHelp, "When a condition is given, instructions will only be logged by the trace logger if the condition returns a value not equal to 0 or false." + Environment.NewLine + Environment.NewLine + frmBreakpoint.GetConditionTooltip(false));
			this.toolTip.SetToolTip(this.picFormatHelp,
				"You can customize the trace logger's output by enabling the 'Override' option and altering the format." + Environment.NewLine + Environment.NewLine +
				"The following tags are available: " + Environment.NewLine +
				"[ByteCode]: The byte code for the instruction (1 to 3 bytes)." + Environment.NewLine +
				"[Disassembly]: The disassembly for the current instruction." + Environment.NewLine +
				"[EffectiveAddress]: The effective address used for indirect addressing modes." + Environment.NewLine +
				"[MemoryValue]: The value stored at the memory location referred to by the instruction." + Environment.NewLine +
				"[PC]: Program Counter" + Environment.NewLine +
				"[A]: A register" + Environment.NewLine +
				"[X]: X register" + Environment.NewLine +
				"[Y]: Y register" + Environment.NewLine +
				"[SP]: Stack Pointer" + Environment.NewLine +
				"[P]: Processor Flags" + Environment.NewLine +
				"[Cycle]: The current PPU cycle." + Environment.NewLine +
				"[Scanline]: The current PPU scanline." + Environment.NewLine +
				"[FrameCount]: The current PPU frame." + Environment.NewLine +
				"[CycleCount]: The current CPU cycle (32-bit signed value, resets to 0 at power on)" + Environment.NewLine + Environment.NewLine +
				"You can also specify some options by using a comma. e.g:" + Environment.NewLine +
				"[Cycle,3] will display the cycle and pad out the output to always be 3 characters wide." + Environment.NewLine +
				"[Scanline,h] will display the scanline in hexadecimal." + Environment.NewLine +
				"[Align,50]: Align is a special tag that is useful when trying to align some content. [Align,50] will make the next tag start on column 50."
			);

			this._initialized = true;
		}

		private void InitShortcuts()
		{
			mnuIncreaseFontSize.InitShortcut(this, nameof(DebuggerShortcutsConfig.IncreaseFontSize));
			mnuDecreaseFontSize.InitShortcut(this, nameof(DebuggerShortcutsConfig.DecreaseFontSize));
			mnuResetFontSize.InitShortcut(this, nameof(DebuggerShortcutsConfig.ResetFontSize));
			mnuRefresh.InitShortcut(this, nameof(DebuggerShortcutsConfig.Refresh));
			mnuCopy.InitShortcut(this, nameof(DebuggerShortcutsConfig.Copy));
			mnuSelectAll.InitShortcut(this, nameof(DebuggerShortcutsConfig.SelectAll));
		}

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

			UpdateMenu();
			tmrUpdateLog.Start();
			RefreshLog(true, true);

			InitShortcuts();
		}

		protected override void OnFormClosing(FormClosingEventArgs e)
		{
			tmrUpdateLog.Stop();
			while(_refreshRunning) {
				System.Threading.Thread.Sleep(50);
			}

			base.OnFormClosing(e);

			DebugInfo debugInfo = ConfigManager.Config.DebugInfo;
			debugInfo.TraceAutoRefresh = mnuAutoRefresh.Checked;
			debugInfo.TraceLineCount = _lineCount;
			debugInfo.TraceLoggerSize = this.WindowState != FormWindowState.Normal ? this.RestoreBounds.Size : this.Size;
			debugInfo.TraceLoggerLocation = this.WindowState != FormWindowState.Normal ? this.RestoreBounds.Location : this.Location;

			debugInfo.TraceFontFamily = txtTraceLog.BaseFont.FontFamily.Name;
			debugInfo.TraceFontSize = txtTraceLog.BaseFont.Size;
			debugInfo.TraceFontStyle = txtTraceLog.BaseFont.Style;
			debugInfo.TraceTextZoom = txtTraceLog.TextZoom;

			_entityBinder.UpdateObject();

			ConfigManager.ApplyChanges();

			if(_loggingEnabled) {
				InteropEmu.DebugStopTraceLogger();
			}
		}

		protected void UpdateFormatOptions()
		{
			if(!chkOverrideFormat.Checked) {
				string format = "[PC,h] ";
				if(chkShowByteCode.Checked) {
					format += "[ByteCode,11h] ";
				}
				format += "[Disassembly]";
				int alignValue = 40;
				if(chkShowEffectiveAddresses.Checked) {
					format += "[EffectiveAddress]";
					alignValue += 8;
				}
				if(chkShowMemoryValues.Checked) {
					format += " [MemoryValue,h]";
					alignValue += 6;
				}
				format += "[Align," + alignValue.ToString() + "] ";

				if(chkShowRegisters.Checked) {
					format += "A:[A,h] X:[X,h] Y:[Y,h] ";
					switch(cboStatusFlagFormat.GetEnumValue<StatusFlagFormat>()) {
						case StatusFlagFormat.Hexadecimal: format += "P:[P,h]"; break;
						case StatusFlagFormat.CompactText: format += "P:[P]"; break;
						case StatusFlagFormat.Text: format += "P:[P,8]"; break;
					}
					format += " SP:[SP,h] ";
				}
				if(chkShowPpuCycles.Checked) {
					format += "CYC:[Cycle,3] ";
				}
				if(chkShowPpuScanline.Checked) {
					format += "SL:[Scanline,3] ";
				}
				if(chkShowFrameCount.Checked) {
					format += "FC:[FrameCount] ";
				}
				if(chkShowCpuCycles.Checked) {
					format += "CPU Cycle:[CycleCount]";
				}
				txtFormat.Text = format.Trim();
			}

			txtFormat.ReadOnly = !chkOverrideFormat.Checked;
			chkShowByteCode.Enabled = !chkOverrideFormat.Checked;
			chkShowRegisters.Enabled = !chkOverrideFormat.Checked;
			chkShowPpuCycles.Enabled = !chkOverrideFormat.Checked;
			chkShowPpuScanline.Enabled = !chkOverrideFormat.Checked;
			chkShowFrameCount.Enabled = !chkOverrideFormat.Checked;
			chkShowCpuCycles.Enabled = !chkOverrideFormat.Checked;
			chkShowEffectiveAddresses.Enabled = !chkOverrideFormat.Checked;
			chkShowMemoryValues.Enabled = !chkOverrideFormat.Checked;
			cboStatusFlagFormat.Enabled = !chkOverrideFormat.Checked;

			if(_initialized) {
				RefreshLog(false, true);
			}
		}

		private void SetOptions()
		{
			_entityBinder.UpdateObject();
			TraceLoggerOptions options = (TraceLoggerOptions)_entityBinder.Entity;

			InteropTraceLoggerOptions interopOptions = new InteropTraceLoggerOptions();
			interopOptions.IndentCode = options.IndentCode;
			interopOptions.ShowExtraInfo = options.ShowExtraInfo;
			interopOptions.UseLabels = options.UseLabels;
			interopOptions.UseWindowsEol = options.UseWindowsEol;
			interopOptions.ExtendZeroPage = options.ExtendZeroPage;

			interopOptions.Condition = Encoding.UTF8.GetBytes(txtCondition.Text);
			Array.Resize(ref interopOptions.Condition, 1000);

			interopOptions.Format = Encoding.UTF8.GetBytes(txtFormat.Text.Replace("\t", "\\t"));
			Array.Resize(ref interopOptions.Format, 1000);

			InteropEmu.DebugSetTraceOptions(interopOptions);
		}

		private void btnStartLogging_Click(object sender, EventArgs e)
		{
			using(SaveFileDialog sfd = new SaveFileDialog()) {
				sfd.SetFilter("Trace logs (*.txt)|*.txt");
				sfd.FileName = "Trace - " + InteropEmu.GetRomInfo().GetRomName() + ".txt";
				sfd.InitialDirectory = ConfigManager.DebuggerFolder;
				if(sfd.ShowDialog() == DialogResult.OK) {
					_lastFilename = sfd.FileName;
					SetOptions();
					InteropEmu.DebugStartTraceLogger(sfd.FileName);

					btnStartLogging.Enabled = false;
					btnStopLogging.Enabled = true;
					btnOpenTrace.Enabled = false;

					_loggingEnabled = true;
				}
			}
		}

		private void btnStopLogging_Click(object sender, EventArgs e)
		{
			InteropEmu.DebugStopTraceLogger();
			btnStartLogging.Enabled = true;
			btnStopLogging.Enabled = false;
			btnOpenTrace.Enabled = true;
		}

		private void btnOpenTrace_Click(object sender, EventArgs e)
		{
			try {
				System.Diagnostics.Process.Start(_lastFilename);
			} catch { }
		}

		private void RefreshLog(bool scrollToBottom, bool forceUpdate)
		{
			if(_refreshRunning) {
				return;
			}

			//Make sure labels are up to date
			DebugWorkspaceManager.GetWorkspace();

			_refreshRunning = true;
			SetOptions();
			Task.Run(() => {
				//Update trace log in another thread for performance
				DebugState state = new DebugState();
				InteropEmu.DebugGetState(ref state);
				if(_previousCycleCount != state.CPU.CycleCount || forceUpdate) {
					string newTrace = InteropEmu.DebugGetExecutionTrace((UInt32)_lineCount);
					_previousCycleCount = state.CPU.CycleCount;
					_previousTrace = newTrace;

					int index = 0;
					string line = null;
					Func<bool> readLine = () => {
						if(index < newTrace.Length) {
							int endOfLineIndex = newTrace.IndexOf('\n', index);
							line = newTrace.Substring(index, endOfLineIndex - index);
							index = endOfLineIndex + 1;
							return true;
						} else {
							return false;
						}
					};

					List<int> programCounter = new List<int>(30000);
					List<string> byteCode = new List<string>(30000);
					List<string> lineContent = new List<string>(30000);
					List<int> indent = new List<int>(30000);

					bool showByteCode = false;
					while(readLine()) {
						string[] parts = line.Split('\x1');
						programCounter.Add(Int32.Parse(parts[0], System.Globalization.NumberStyles.HexNumber));
						byteCode.Add(parts[1]);

						string content = parts[2];
						while(true) {
							string str = content.TrimStart();
							if(str.StartsWith(parts[0])) {
								content = str.Substring(4);
							} else if(str.StartsWith(parts[1])) {
								content = str.Substring(11);
								showByteCode = true;
							} else if(str.StartsWith(parts[1].Replace("$", ""))) {
								content = str.Substring(8);
								showByteCode = true;
							} else {
								break;
							}
						}
						lineContent.Add(content);
						indent.Add(0);
					}
					this.BeginInvoke((Action)(() => {
						txtTraceLog.ShowContentNotes = showByteCode;
						txtTraceLog.ShowSingleContentLineNotes = showByteCode;

						txtTraceLog.LineIndentations = indent.ToArray();
						txtTraceLog.LineNumbers = programCounter.ToArray();
						txtTraceLog.TextLineNotes = byteCode.ToArray();
						txtTraceLog.TextLines = lineContent.ToArray();

						if(scrollToBottom) {
							txtTraceLog.ScrollToLineIndex(txtTraceLog.LineCount - 1);
						}
					}));
				}
				_refreshRunning = false;
			});
		}

		private void UpdateMenu()
		{
			mnu30000Lines.Checked = _lineCount == 30000;
			mnu15000Lines.Checked = _lineCount == 15000;
			mnu10000Lines.Checked = _lineCount == 10000;
			mnu5000Lines.Checked = _lineCount == 5000;
			mnu1000Lines.Checked = _lineCount == 1000;
			mnu100Lines.Checked = _lineCount == 100;

			if(_lineCount >= 1000) {
				tmrUpdateLog.Interval = 250;
			} else {
				tmrUpdateLog.Interval = 150;
			}
		}

		private void tmrUpdateLog_Tick(object sender, EventArgs e)
		{
			if(txtCondition.Text.Length > 0) {
				EvalResultType resultType;
				InteropEmu.DebugEvaluateExpression(txtCondition.Text, out resultType, false);
				picExpressionWarning.Visible = (resultType == EvalResultType.Invalid);
			} else {
				picExpressionWarning.Visible = false;
			}

			if(mnuAutoRefresh.Checked) {
				RefreshLog(false, false);
			}
		}

		private void SetLineCount(int count)
		{
			_lineCount = count;
			UpdateMenu();
			RefreshLog(false, true);
		}

		private void mnu30000Lines_Click(object sender, EventArgs e)
		{
			SetLineCount(30000);
		}

		private void mnu15000Lines_Click(object sender, EventArgs e)
		{
			SetLineCount(15000);
		}

		private void mnu10000Lines_Click(object sender, EventArgs e)
		{
			SetLineCount(10000);
		}

		private void mnu5000Lines_Click(object sender, EventArgs e)
		{
			SetLineCount(5000);
		}

		private void mnu1000Lines_Click(object sender, EventArgs e)
		{
			SetLineCount(1000);
		}

		private void mnu100Lines_Click(object sender, EventArgs e)
		{
			SetLineCount(100);
		}

		private void mnuRefresh_Click(object sender, EventArgs e)
		{
			RefreshLog(false, true);
		}

		private void mnuIncreaseFontSize_Click(object sender, EventArgs e)
		{
			txtTraceLog.TextZoom += 10;
		}

		private void mnuDecreaseFontSize_Click(object sender, EventArgs e)
		{
			txtTraceLog.TextZoom -= 10;
		}

		private void mnuResetFontSize_Click(object sender, EventArgs e)
		{
			txtTraceLog.TextZoom = 100;
		}

		private void mnuSelectFont_Click(object sender, EventArgs e)
		{
			txtTraceLog.BaseFont = FontDialogHelper.SelectFont(txtTraceLog.BaseFont);
		}

		private void chkOptions_CheckedChanged(object sender, EventArgs e)
		{
			UpdateFormatOptions();
		}

		private void cboStatusFlagFormat_SelectedIndexChanged(object sender, EventArgs e)
		{
			UpdateFormatOptions();
		}

		private void txtFormat_TextChanged(object sender, EventArgs e)
		{
			if(chkOverrideFormat.Checked) {
				//Only save format string when override flag is set
				((TraceLoggerOptions)_entityBinder.Entity).Format = txtFormat.Text;
			}
		}

		private void chkOverrideFormat_CheckedChanged(object sender, EventArgs e)
		{
			if(chkOverrideFormat.Checked) {
				string format = ((TraceLoggerOptions)_entityBinder.Entity).Format;
				if(string.IsNullOrWhiteSpace(format)) {
					format = txtFormat.Text;
				}
				txtFormat.Text = format;
			}
			UpdateFormatOptions();
		}

		private void mnuCopy_Click(object sender, EventArgs e)
		{
			string[] lines = _previousTrace.Split('\n');
			StringBuilder sb = new StringBuilder();
			for(int i = txtTraceLog.SelectionStart, end = txtTraceLog.SelectionStart + txtTraceLog.SelectionLength; i <= end && i < lines.Length; i++) {
				sb.Append(lines[i]);
			}
			Clipboard.SetText(sb.ToString());

			txtTraceLog.CopySelection(true, true, false);
		}

		private void mnuSelectAll_Click(object sender, EventArgs e)
		{
			txtTraceLog.SelectAll();
		}
	}
}