using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;
using System.Configuration;
using System.IO;
using System.Runtime.Serialization.Json;
using System.Runtime.Serialization.Formatters;

//this version has been modified to not split each #check into an individual test

namespace Microsoft.Sputnik.Interop.ParserEngine
{
    public static class ES5TestScript
    {
        private static int fileCounter;
        private static StringBuilder negativeTestCases;
        private static string globalScopeFileName = "\\SputnikGlobalScope.js";


        private static string[] templates = {


           ES5TestScript.GetTemplateFile(ResourceClass.BasicTemplate_FileName),
           ES5TestScript.GetTemplateFile(ResourceClass.BasicPrereqTemplate_FileName),
           ES5TestScript.GetTemplateFile(ResourceClass.BasicNegativeTemplate_FileName),
           ES5TestScript.GetTemplateFile(ResourceClass.BasicNegativePrereqTemplate_FileName)
         };

        /// <summary>
        /// Output files counter
        /// </summary>
        public static int OutputFileCounter
        {
            get
            {
                return fileCounter;
            }
            set
            {
                fileCounter = value;
            }
        }
        /// <summary>
        /// Method to save the sputnik scripts in ES5 format
        /// </summary>
        /// <param name="script">SputnikTestScript Object which will have all the details to be written to the file</param>
        /// <param name="destinationPath">Is the destination folder path</param>
        public static void Save(SputnikTestScript script, string root, string destinationPath)
        {
            string destDir = Path.Combine(destinationPath, Path.GetDirectoryName(script.pathFromRoot));
            string buildContent = string.Empty;
            string destFullPath = string.Empty;
            string preCondition = string.IsNullOrEmpty(script.PreConditionCode) ? String.Empty : script.PreConditionCode;
            int templateIndex = string.IsNullOrEmpty(preCondition) ? 0 : 1;
            string body = script.Body;
            if (script.IsNegative)
            {
                templateIndex += 2;
            }
            string template = templates[templateIndex];
            Logger.WriteToLog("=====================================================================================");
            Logger.WriteToLog("Source file={0}\n", script.FullPath);
            Logger.WriteToLog("Destination(s)=");
            if (script.id == "")
            {
                Console.Write(script.Header);
                Console.WriteLine();
            }

            string[] args = { script.Header, script.id, script.path, InsertStringEscapes(script.assertion), InsertStringEscapes(script.description), script.ReplicationCode, body, preCondition, script.InitialComment };
            destFullPath = Path.Combine(destDir, string.Format(@"{0}.js", script.id));

            try
            {
                buildContent = string.Format(template, args);
                string dirPath = Path.GetDirectoryName(destFullPath);
                if (!Directory.Exists(dirPath))
                    Directory.CreateDirectory(dirPath);
                using (TextWriter writeTestCase = File.CreateText(destFullPath))
                {
                    writeTestCase.WriteLine(buildContent);
                    writeTestCase.Flush();
                    writeTestCase.Close();
                    OutputFileCounter++;
                }

                if (script.IsNegative)
                {
                    //Add details in stringbuilder.
                    StringBuilder sb = new StringBuilder();
                    //sb.Append("GlobalScopeTests[script.pathFromRoot.Replace("\\", "/") + "\"]");
                    sb.Append("GlobalScopeTests[\"" + script.id + "\"]");
                    sb.Append("=");
                    string s = GetSerializedSputnikTestScript(new SputnikTestScript()
                                                                    {
                                                                        id = script.id,
                                                                        path = script.path,
                                                                        description = script.description,
                                                                        assertion = script.assertion,
                                                                    });
                    sb.Append(s.Substring(0, s.LastIndexOf('}')) + ",\"negative\":\".\"};");

                    if (negativeTestCases == null)
                    {
                        negativeTestCases = new StringBuilder();
                    }
                    else
                    {
                        negativeTestCases.Append("\n");
                    }
                    negativeTestCases.Append(sb.ToString());
                }

                Logger.WriteToLog(destFullPath);
            }
            catch (ArgumentException ex)
            {
                Logger.WriteToLog(ResourceClass.IOException, ex.Message);
            }
            catch (IOException ex)
            {
                Logger.WriteToLog(ResourceClass.IOException, ex.Message);
            }
            //           }
        }

        /// <summary>
        /// Method to initialize the negative test record.
        /// </summary>
        /// <param name="destination">Is the destination folder path</param>
        public static void InitGlobals(string destination)
        {
            //Insert inital var name in Globals.js file.
            if (!Directory.Exists(destination))
            {
                Directory.CreateDirectory(destination);
            }
            FileStream fs = new FileStream(destination.Remove(destination.LastIndexOf("\\")) + globalScopeFileName, FileMode.Create, FileAccess.Write);
            StreamWriter sw = new StreamWriter(fs);
            sw.Write("this.GlobalScopeTests = this.GlobalScopeTests || new Array();\n");
            sw.Flush();
            sw.Close();
            fs.Close();
        }

        /// <summary>
        /// Method to update the SputnikGlobalScope.js
        /// </summary>
        /// <param name="destination">Is the destination folder path</param>
        public static void UpdateGlobals(string destination)
        {
            //Replace the last comma by closing curly brace and semi-colon.
            File.AppendAllText(destination.Remove(destination.LastIndexOf("\\")) + globalScopeFileName, negativeTestCases.ToString());
            negativeTestCases.Clear();
        }


        private static string GetSerializedSputnikTestScript(SputnikTestScript sputnikTestScript)
        {
            MemoryStream stream = new MemoryStream();
            DataContractJsonSerializer ser = new DataContractJsonSerializer(typeof(SputnikTestScript));
            ser.WriteObject(stream, sputnikTestScript);

            stream.Position = 0;
            StreamReader sr = new StreamReader(stream);

            return sr.ReadToEnd();
        }

        private static string WrapWithEval(string s)
        {
            return InsertStringEscapes(s, true);
        }

        private static string InsertStringEscapes(string s, bool wrapWithEval = false)
        {
            StringReader rdr = new StringReader(s);
            StringWriter wtr = new StringWriter();
            int intChar;
            char nextChar;
            if (wrapWithEval) wtr.Write("eval(\"");
            while (true)
            {
                intChar = rdr.Read();
                if (intChar == -1) break;
                nextChar = Convert.ToChar(intChar);
                switch (nextChar)
                {
                    case '\\':
                    case '\'':
                    case '"':
                        wtr.Write('\\');
                        wtr.Write(nextChar);
                        break;
                    case '\n':
                        wtr.Write("\\n");
                        break;
                    case '\r':
                        wtr.Write("\\r");
                        break;
                    case '\u2028':
                        wtr.Write("\\u2028");
                        break;
                    case '\u2029':
                        wtr.Write("\\u2029");
                        break;
                    default:
                        wtr.Write(nextChar);
                        break;
                }
            }
            if (wrapWithEval) wtr.Write("\")");
            return wtr.ToString();
        }

        /// <summary>
        /// Method to read the templates which are used to generate a ES5 format files.
        /// </summary>
        /// <returns></returns>
        private static string GetTemplateFile(string configSetting)
        {
            string inputTemplatePath = ConfigurationManager.AppSettings[configSetting].ToString();
            return (new StreamReader(inputTemplatePath)).ReadToEnd();
        }
    }
}