using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Reflection;
using Convention;
using UnityEngine;

namespace Demo.Editor
{
	public static class ProjectCreateHelper
	{
		private static string GetTypename(Type type)
        {
            string result = type.Name;
            if (result.Contains('`'))
				return result[..result.LastIndexOf('`')];
            return result;
        }

        private static void WritePythonStyleFunction(StreamWriter stream, string name, IEnumerable<string> paramList, string description)
        {
            stream.Write($"def {name}({string.Join(',', paramList)}):\n");
			stream.Write($"'''\n{description}\n'''\n...\n\n");
        }

		private static void WriteCPPClassBase(StreamWriter stream, Type currentType)
        {
			string currentTypeName = GetTypename(currentType);
			string baseTypeName = GetTypename(currentType.BaseType);
            if (currentType == typeof(ScriptableObject))
			{
				// 绘制工具宏
				stream.WriteLine("#define __build_in_pragma #");
				stream.WriteLine("#define __build_in_to_text(x) #x");
				stream.WriteLine("#define this");
				// 绘制类定义标识符
				foreach (var asm in AppDomain.CurrentDomain.GetAssemblies())
				{
					foreach (var type in asm.GetTypes())
					{
						// Functions
						if (typeof(ScriptableObject).IsAssignableFrom(type))
						{
							string typeName = GetTypename(type);
                            stream.WriteLine($"#define {typeName} \"{typeName}\"");
						}
					}
				}
				// 绘制Mathf
				foreach (var method in typeof(Mathf).GetMethods())
				{
					stream.WriteLine($"#define {method.Name}({string.Join(',', from param in method.GetParameters() select param.Name)})");
				}
				foreach (var curveType in Enum.GetNames(typeof(MathExtension.EaseCurveType)))
				{
					stream.WriteLine($"#define {curveType}");
				}
				// 绘制RScript关键词
				{
					stream.Write(@"
/*
控制流标签
*/
");
					stream.Write($"#define label(label_name) __build_in_pragma define label_name\n\n");
				}
				{
					stream.Write(@"
/*
控制流, 当pr为真时跳转到指定的label处
*/
");
					stream.Write($"#define goto(pr,label_name)\n\n");
				}
				{
					stream.Write(@"
/*
控制流, 当pr为真时返回上一次调用goto的位置, 栈模式
*/
");
					stream.Write($"#define back(pr)\n\n");
				}
				{
					stream.Write(@"
/*
控制流, 当pr为真时退出当前命名空间
*/
");
					stream.Write($"#define break(pr)\n\n");
				}
				{
					stream.Write(@"
/*
赋名命名空间, 具有名称的命名空间将不会自动运行, 需要使用goto到达
*/
");
					stream.Write($"#define namespace(name)\n\n");
				}
				stream.WriteLine($"struct {currentTypeName}");
				stream.WriteLine("{");
            }
			else
			{
				stream.Write($"#include \"{baseTypeName}.helper.h\"\n\n");
                stream.WriteLine($"struct {currentTypeName}:public {baseTypeName}");
                stream.WriteLine("{");
            }
        }

		private static void WriteCPPStyleFunction(StreamWriter stream, string name, IEnumerable<string> paramList, string description)
		{
			if (name == nameof(ScriptableObject.LoadSubScript))
			{
				stream.Write("/*\n" + description + "\n*/\n");
				stream.Write($"#define {name}({string.Join(',', paramList)}) __build_in_pragma include {paramList.ToArray()[1]}\n\n");
				//stream.Write($"#define {name}({string.Join(',', paramList)})\n\n");
			}
			else
			{
				stream.Write("/*\n" + description + "\n*/\n");
				stream.Write($"#define {name}({string.Join(',', paramList)}) \n\n");
			}
        }

		private static void WriteCPPClassEnd(StreamWriter stream, Type currentType)
		{
			stream.WriteLine("};");
		}


        public static void CreateHelperFiles(string dir, ProjectDefaultFileStyle style = ProjectDefaultFileStyle.CPP)
		{
			var toolDir = new ToolFile(dir);
			if (toolDir.IsDir() == false)
			{
				throw new InvalidOperationException("Not a directory");
			}
            toolDir.MustExistsPath();
			foreach (var asm in AppDomain.CurrentDomain.GetAssemblies())
			{
				foreach (var type in asm.GetTypes())
				{
					// Functions
					if (typeof(ScriptableObject).IsAssignableFrom(type))
					{
						var scriptCalls = (from info in type.GetMembers(BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly)
										   where info is MethodInfo
										   where info.GetCustomAttribute<ScriptableCallAttribute>(false) != null
										   select info as MethodInfo).ToList();
						var typeName = GetTypename(type);
                        string fileHeader = $"{typeName}.helper" + style switch
						{
							ProjectDefaultFileStyle.PY => ",py",
							_ => ".h"
						};
						using var fs = File.AppendText((toolDir | fileHeader).GetFullPath());
						switch (style)
						{
							case ProjectDefaultFileStyle.CPP:
								WriteCPPClassBase(fs, type);
								break;
							case ProjectDefaultFileStyle.PY:
								break;
						}
						foreach (var methodInfo in scriptCalls)
						{
							var data = methodInfo.GetCustomAttribute<ScriptableCallAttribute>(false);
							switch (style)
							{
								case ProjectDefaultFileStyle.PY:
									WritePythonStyleFunction(fs, methodInfo.Name, from param in methodInfo.GetParameters() select param.Name, data.Description);
									break;
								default:
									WriteCPPStyleFunction(fs, methodInfo.Name, from param in methodInfo.GetParameters() select param.Name, data.Description);
									break;
							}
                        }
                        switch (style)
                        {
                            case ProjectDefaultFileStyle.CPP:
                                WriteCPPClassEnd(fs, type);
                                break;
                            case ProjectDefaultFileStyle.PY:
                                break;
                        }
                    }
					// Enums
					if (typeof(Enum).IsAssignableFrom(type)&& type.GetCustomAttribute<ScriptableCallAttribute>(false) != null)
					{
						// TODO
					}
                }
			}
		}
	}
}