// Copyright (c) AlphaSierraPapa for the SharpDevelop Team
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy of this
// software and associated documentation files (the "Software"), to deal in the Software
// without restriction, including without limitation the rights to use, copy, modify, merge,
// publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons
// to whom the Software is furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all copies or
// substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
// INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE
// FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Globalization;
using System.IO;
using System.Text.RegularExpressions;

namespace ICSharpCode.NRefactory.Utils
{
	/// <summary>
	/// GraphViz graph.
	/// </summary>
	public sealed class GraphVizGraph
	{
		List<GraphVizNode> nodes = new List<GraphVizNode>();
		List<GraphVizEdge> edges = new List<GraphVizEdge>();
		
		public string rankdir;
		public string Title;
		
		public void AddEdge(GraphVizEdge edge)
		{
			edges.Add(edge);
		}
		
		public void AddNode(GraphVizNode node)
		{
			nodes.Add(node);
		}
		
		public void Save(string fileName)
		{
			using (StreamWriter writer = new StreamWriter(fileName))
				Save(writer);
		}
		
		public void Show()
		{
			Show(null);
		}
		
		public void Show(string name)
		{
			if (name == null)
				name = Title;
			if (name != null)
				foreach (char c in Path.GetInvalidFileNameChars())
					name = name.Replace(c, '-');
			string fileName = name != null ? Path.Combine(Path.GetTempPath(), name) : Path.GetTempFileName();
			Save(fileName + ".gv");
			Process.Start("dot", "\"" + fileName + ".gv\" -Tpng -o \"" + fileName + ".png\"").WaitForExit();
			Process.Start(fileName + ".png");
		}
		
		static string Escape(string text)
		{
			if (Regex.IsMatch(text, @"^[\w\d]+$")) {
				return text;
			} else {
				return "\"" + text.Replace("\\", "\\\\").Replace("\r", "").Replace("\n", "\\n").Replace("\"", "\\\"") + "\"";
			}
		}
		
		static void WriteGraphAttribute(TextWriter writer, string name, string value)
		{
			if (value != null)
				writer.WriteLine("{0}={1};", name, Escape(value));
		}
		
		internal static void WriteAttribute(TextWriter writer, string name, double? value, ref bool isFirst)
		{
			if (value != null) {
				WriteAttribute(writer, name, value.Value.ToString(CultureInfo.InvariantCulture), ref isFirst);
			}
		}
		
		internal static void WriteAttribute(TextWriter writer, string name, bool? value, ref bool isFirst)
		{
			if (value != null) {
				WriteAttribute(writer, name, value.Value ? "true" : "false", ref isFirst);
			}
		}
		
		internal static void WriteAttribute(TextWriter writer, string name, string value, ref bool isFirst)
		{
			if (value != null) {
				if (isFirst)
					isFirst = false;
				else
					writer.Write(',');
				writer.Write("{0}={1}", name, Escape(value));
			}
		}
		
		public void Save(TextWriter writer)
		{
			if (writer == null)
				throw new ArgumentNullException("writer");
			writer.WriteLine("digraph G {");
			writer.WriteLine("node [fontsize = 16];");
			WriteGraphAttribute(writer, "rankdir", rankdir);
			foreach (GraphVizNode node in nodes) {
				node.Save(writer);
			}
			foreach (GraphVizEdge edge in edges) {
				edge.Save(writer);
			}
			writer.WriteLine("}");
		}
	}
	
	public sealed class GraphVizEdge
	{
		public readonly string Source, Target;
		
		/// <summary>edge stroke color</summary>
		public string color;
		/// <summary>use edge to affect node ranking</summary>
		public bool? constraint;
		
		public string label;
		
		public string style;
		
		/// <summary>point size of label</summary>
		public int? fontsize;
		
		public GraphVizEdge(string source, string target)
		{
			if (source == null)
				throw new ArgumentNullException("source");
			if (target == null)
				throw new ArgumentNullException("target");
			this.Source = source;
			this.Target = target;
		}
		
		public GraphVizEdge(int source, int target)
		{
			this.Source = source.ToString(CultureInfo.InvariantCulture);
			this.Target = target.ToString(CultureInfo.InvariantCulture);
		}
		
		public void Save(TextWriter writer)
		{
			writer.Write("{0} -> {1} [", Source, Target);
			bool isFirst = true;
			GraphVizGraph.WriteAttribute(writer, "label", label, ref isFirst);
			GraphVizGraph.WriteAttribute(writer, "style", style, ref isFirst);
			GraphVizGraph.WriteAttribute(writer, "fontsize", fontsize, ref isFirst);
			GraphVizGraph.WriteAttribute(writer, "color", color, ref isFirst);
			GraphVizGraph.WriteAttribute(writer, "constraint", constraint, ref isFirst);
			writer.WriteLine("];");
		}
	}
	
	public sealed class GraphVizNode
	{
		public readonly string ID;
		public string label;
		
		public string labelloc;
		
		/// <summary>point size of label</summary>
		public int? fontsize;
		
		/// <summary>minimum height in inches</summary>
		public double? height;
		
		/// <summary>space around label</summary>
		public string margin;
		
		/// <summary>node shape</summary>
		public string shape;
		
		public GraphVizNode(string id)
		{
			if (id == null)
				throw new ArgumentNullException("id");
			this.ID = id;
		}
		
		public GraphVizNode(int id)
		{
			this.ID = id.ToString(CultureInfo.InvariantCulture);
		}
		
		public void Save(TextWriter writer)
		{
			writer.Write(ID);
			writer.Write(" [");
			bool isFirst = true;
			GraphVizGraph.WriteAttribute(writer, "label", label, ref isFirst);
			GraphVizGraph.WriteAttribute(writer, "labelloc", labelloc, ref isFirst);
			GraphVizGraph.WriteAttribute(writer, "fontsize", fontsize, ref isFirst);
			GraphVizGraph.WriteAttribute(writer, "margin", margin, ref isFirst);
			GraphVizGraph.WriteAttribute(writer, "shape", shape, ref isFirst);
			writer.WriteLine("];");
		}
	}
}