using System;
using System.Collections.Generic;
using System.Collections;
using System.Text;
using System.IO;
using MySql.Data.MySqlClient;
using System.Data;

namespace CopyDb
{
  public class Constants
	{
	  public static String IBD_EXTENSION=".ibd";
		public static int COMMAND_TIMEOUT=0;  // no timeout
		public static string CHARACTER_SET="utf8mb4";
		public static string COLLATION="utf8mb4_0900_ai_ci";
	}
  public class Schemas : List<Schema>
	{
	  	public void Display()
		{
		  for(int index=0;index<Count;index++)
			{
			  Console.WriteLine(String.Format("{0}){1}",index+1,this[index].TableName));
			}
		}
	}
  public class Schema
	{						
	  public Schema()
		{
		  SchemaLines=new List<String>();
			HasForeignKey=false;
		}
	  public List<String> SchemaLines{get;set;}
		public String TableName{get;set;}
		public bool HasForeignKey{get;set;}
		public String ForeignKeyTable{get;set;}
		public String ForeignKeyConstraint{get;set;}
	}
// ******************************************************************

  public class Config
  {
    public String Server{get;set;}
    public int Port{get;set;}
    public String Database{get;set;}
		public String User{get;set;}
		public String Password{get;set;}
		public String PathSchemaFileName{get;set;}
		public String PathIbd{get;set;}
		public String Mode{get;set;}
		public String DatabaseDirectory{get;set;}
		public String CharacterSet{get;set;}
		public String Collation{get;set;}
		
		public void Display()
		{
		  Console.WriteLine(String.Format("SERVER:{0}",Server));
		  Console.WriteLine(String.Format("PORT:{0}",Port));
		  Console.WriteLine(String.Format("DATABASE:{0}",Database));
		  Console.WriteLine(String.Format("USER:{0}",User));
		  Console.WriteLine(String.Format("PASSWORD:{0}",Password));
		  Console.WriteLine(String.Format("PATHSCHEMAFILE:{0}",PathSchemaFileName));
		  Console.WriteLine(String.Format("PATHIBD:{0}",PathIbd));
		  Console.WriteLine(String.Format("MODE:{0}",Mode));
		  Console.WriteLine(String.Format("DATABASEDIRECTORY:{0}",DatabaseDirectory));
		  Console.WriteLine(String.Format("CHARACTERSET:{0}",CharacterSet));
		  Console.WriteLine(String.Format("COLLATION:{0}",Collation));
		}
  }
  class Program
  {
    static void Main(string[] args)
    {
      if(1==args.Length)
      {
        Console.WriteLine(String.Format("USAGE: COPYDB /SERVER:{server} /PORT:{port} /ROWCOUNTSONLY:{true|false} /CONVERTCHARSETCOLLATION:{charset@collation} /DATABASE:{databasename} /USER:{username} /PASSWORD:{password} /PATHSCHEMAFILE:{pathschemafilename} /PATHIDB:{pathibdfiles} /MODE:{LIVE|TEST} /DATABASEDIRECTORY:{path}"));
        return;
      }
			PerformImport(args);
		}
		public static void PerformImport(string[] args)
		{
		  String strResult=null;
      CommandArgs commandArgs=new CommandArgs(args);

			Console.WriteLine("*********** C O N F I G ***********");
			Config config=GetConfig(commandArgs);
			config.Display();

			if(!commandArgs.Has("SERVER,PORT,DATABASE,USER,PASSWORD,PATHSCHEMAFILE"))
			{
        Console.WriteLine(String.Format("One or more required parameters are missing.  SERVER,PORT,DATABASE,USER,PASSWORD,PATHSCHEMAFILE"));
        return;
			}

// ************************************************************* S C H E M A *******************************************************
			Schemas schemas=Program.GetSchemas(config);
			if(null==schemas)
			{
			  Console.WriteLine(String.Format("Unable to read schemas"));
				return;
			}
			Console.WriteLine("*********** S C H E M A ***********");
			schemas.Display();

// ***********************************************************  D A T A B A S E ********************************************************
			Console.WriteLine("*********** V E R I F Y I N G  D A T A B A S E  ***********");
			MySqlConnection sqlConnection=null;
			try{	sqlConnection=SqlUtils.CreateMySqlConnection(config.Server,config.Port.ToString(),config.Database,config.User,config.Password);}
			catch(Exception exception)
			{
			  Console.WriteLine(String.Format("Encountered Exception: {0}",exception.ToString()));
				return;
			}
			ConnectionState connectionState=sqlConnection.State;
			if(!connectionState.Equals(ConnectionState.Open))
			{
			  Console.WriteLine(String.Format("Unable to connect to databse {0}",config.Database));
				return;
			}
			Console.WriteLine("Database connection verified.");
// ***************************************************** T A B L E  R O W  C O U N T S***********************************************************
      GetTableRowCounts(schemas, config, sqlConnection);

      if(commandArgs.Has("ROWCOUNTSONLY") && commandArgs.Get<bool>("ROWCOUNTSONLY").Equals(true))
      {
        Console.WriteLine("Exiting because ROWCOUNTSONLY is set to True.");
        return;
      }

// *********************************************************************************************************************************************
// (i.e.) CONVERTCHARSETCOLLATION:utf8mb4@utf8mb4_0900_ai_ci
			if(commandArgs.Has("CONVERTCHARSETCOLLATION"))
			{
				Console.WriteLine("**WARNING** This is a destructive event.  This process will convert tables in {0}",config.Database);
				Console.WriteLine("Please review settings.  Proceed Y/N?");
				strResult=Console.ReadLine();
				if(null==strResult||(!strResult.ToUpper().Equals("Y") && !strResult.ToUpper().Equals("YES")))
				{
					Console.WriteLine("Cancelled");
					return;
				}
			  ConvertSchema(schemas ,config, sqlConnection);	
				GetTableRowCounts(schemas, config, sqlConnection);
			  Console.WriteLine("Done.");
				Console.ReadLine();
				return;
			}

      if(!commandArgs.Has("PATHIBD,MODE,DATABASEDIRECTORY"))
      {
        Console.WriteLine(String.Format("One or more required parameters are missing."));
        return;
      }

			Console.WriteLine("*********** V E R I F Y I N G  I D B F I L E S  ***********");
			if(!VerifyIdbFiles(schemas,config))
			{
			  Console.WriteLine("Unable to verify IDBFiles");
				return;
			}

			if(config.Mode.ToUpper().Equals("TEST"))
			{
			  Console.WriteLine("Mode is TEST.");
				sqlConnection.Close();
				sqlConnection.Dispose();
				return;
			}

		  Console.WriteLine("**WARNING** This is a destructive event.  This process will drop tables in {0}",config.Database);
		  Console.WriteLine("Please review settings.  Proceed Y/N?");
			strResult=Console.ReadLine();
			if(null==strResult||(!strResult.ToUpper().Equals("Y") && !strResult.ToUpper().Equals("YES")))
			{
			  Console.WriteLine("Cancelled");
			  return;
			}

			Console.WriteLine("*********** I M P O R T  ***********");
			foreach(Schema schema in schemas)
			{
			  ImportTable(schema ,config, sqlConnection);
			}
			sqlConnection.Close();
			sqlConnection.Dispose();
			Console.WriteLine("Done.");
      return;
		}
// ********************************************************************************************************************************************************************************
// *************************************************************************** C O N V E R T  C H A R A C T E R   S E T ***********************************************************
// ********************************************************************************************************************************************************************************
		private static void ConvertSchema(Schemas schemas, Config config, MySqlConnection sqlConnection)
		{
			MySqlCommand sqlCommand=null;
			String strSetKeyChecksTrue="SET foreign_key_checks =1;";
			String strSetKeyChecksFalse="SET foreign_key_checks =0;";

		  try
			{
			  Console.WriteLine(String.Format("{0}",strSetKeyChecksFalse));
				sqlCommand = new MySqlCommand(strSetKeyChecksFalse, sqlConnection);               
				sqlCommand.CommandTimeout=Constants.COMMAND_TIMEOUT;
				sqlCommand.ExecuteNonQuery();
				sqlCommand.Dispose();

				foreach(Schema schema in schemas)
				{
					StringBuilder sb=new StringBuilder();
					sb.Append("ALTER TABLE ").Append(schema.TableName).Append(" CONVERT TO CHARACTER SET ").Append(config.CharacterSet).Append(" COLLATE ").Append(config.Collation).Append(" ;");
					String strQuery=sb.ToString();
					Console.WriteLine(String.Format(strQuery));
					sqlCommand = new MySqlCommand(strQuery, sqlConnection);               
					sqlCommand.CommandTimeout=Constants.COMMAND_TIMEOUT;
					sqlCommand.ExecuteNonQuery();
					sqlCommand.Dispose();
					if(!VerifyCharSetCollation(schema.TableName, config, sqlConnection))
					{
					  Console.WriteLine(String.Format("FAILED to change character set / collation on table {0}",schema.TableName));
					}
					else Console.WriteLine(String.Format("VERIFIED"));
				}
			  Console.WriteLine(String.Format("{0}",strSetKeyChecksTrue));
				Console.WriteLine("");
				sqlCommand = new MySqlCommand(strSetKeyChecksTrue, sqlConnection);               
				sqlCommand.CommandTimeout=Constants.COMMAND_TIMEOUT;
				sqlCommand.ExecuteNonQuery();
				sqlCommand.Dispose();

			}
			catch(Exception exception)
			{
			  if(null!=sqlCommand)
				{
				  sqlCommand.Dispose();
					sqlCommand=null;
				}
			  Console.WriteLine("Exception converting character set :{0}",exception.ToString());
	   	}
		}
// ********************************************************************************************************************************************************************************
// *************************************************************************** V E R I F Y  C H A R A C T E R   S E T ***********************************************************
// ********************************************************************************************************************************************************************************
		private static bool VerifyCharSetCollation(String tableName, Config config, MySqlConnection sqlConnection)
		{
			MySqlCommand sqlCommand=null;
			MySqlDataReader sqlReader=null;
			bool verified=true;

		  try
			{
					StringBuilder sb=new StringBuilder();
					sb.Append("SHOW FULL COLUMNS FROM ").Append(tableName).Append(" ;");
					sqlCommand=sqlConnection.CreateCommand();
					sqlCommand.CommandTimeout=Constants.COMMAND_TIMEOUT;
					String strQuery=sb.ToString();
					Console.WriteLine(String.Format(strQuery));
					sqlCommand = new MySqlCommand(strQuery, sqlConnection); 
					sqlReader=sqlCommand.ExecuteReader();
					while(sqlReader.Read())
					{
					  String field=sqlReader.IsDBNull(0)?null:sqlReader.GetString(0);
					  String type=sqlReader.IsDBNull(1)?null:sqlReader.GetString(1).ToLower();
						String collation=sqlReader.IsDBNull(2)?null:sqlReader.GetString(2).ToLower();
						if(!type.StartsWith("varchar"))continue;
						if(!collation.Equals(config.Collation))verified=false;
					}
					sqlReader.Close();
					sqlReader.Dispose();
					sqlCommand.Dispose();
					sqlCommand=null;
					sqlReader=null;
					return verified;
			}
			catch(Exception exception)
			{
			  Console.WriteLine("Exception converting character set :{0}",exception.ToString());
				if(null!=sqlReader)
				{
				  sqlReader.Close();
					sqlReader.Dispose();
				}
			  if(null!=sqlCommand)
				{
				  sqlCommand.Dispose();
					sqlCommand=null;
				}
				return false;
	   	}
		}
// ********************************************************************************************************************************************************************************
// ******************************************************************************** T A B L E  R O W  C O U N T S  ***********************************************************************
// ********************************************************************************************************************************************************************************
		private static void GetTableRowCounts(Schemas schemas, Config config, MySqlConnection sqlConnection)
		{
			MySqlCommand sqlCommand=null;
			MySqlDataReader sqlReader=null;

		  try
			{
			  foreach(Schema schema in schemas)
				{
					StringBuilder sb=new StringBuilder();
					sb.Append("SELECT COUNT(*) FROM ").Append(schema.TableName).Append(" ;");
					sqlCommand=sqlConnection.CreateCommand();
					sqlCommand.CommandTimeout=Constants.COMMAND_TIMEOUT;
					String strQuery=sb.ToString();
					sqlCommand = new MySqlCommand(strQuery, sqlConnection);               
					sqlReader=sqlCommand.ExecuteReader();
					while(sqlReader.Read())
					{
					  int rows=sqlReader.GetInt32(0);
						Console.WriteLine(String.Format("{0},{1}",schema.TableName,Utility.FormatNumber(rows,0,false)));
					}
					sqlReader.Close();
					sqlReader.Dispose();
					sqlCommand.Dispose();
					sqlCommand=null;
					sqlReader=null;
				}
			}
			catch(Exception exception)
			{
			  Console.WriteLine("Exception:{0}",exception.ToString());
				if(null!=sqlReader)
				{
				  sqlReader.Close();
					sqlReader.Dispose();
				}
			  if(null!=sqlCommand)
				{
				  sqlCommand.Dispose();
					sqlCommand=null;
				}
	   	}
		}

// *****************************************************************************************************************************************************
// *************************************************************** I M P O R T  T A B L E **************************************************************
// *****************************************************************************************************************************************************
		private static void ImportTable(Schema schema, Config config,MySqlConnection sqlConnection)
		{
			MySqlTransaction sqlTransaction=null;
			String pathIdbFile=null;
			String pathIdbFileDestination=null;

			try
			{
			  MySqlCommand sqlCommand=null;
				String strQuery=null;
				StringBuilder sb=null;
				pathIdbFile=config.PathIbd+"\\"+schema.TableName+".ibd";
				pathIdbFileDestination=config.DatabaseDirectory+"\\"+schema.TableName+".ibd";
				sqlTransaction=sqlConnection.BeginTransaction(IsolationLevel.RepeatableRead);

				sb=new StringBuilder();
				sb.Append("DROP TABLE IF EXISTS ").Append(schema.TableName).Append(";");
				sqlCommand=sqlConnection.CreateCommand();
				sqlCommand.CommandTimeout=Constants.COMMAND_TIMEOUT;
				strQuery=sb.ToString();
				Console.WriteLine(String.Format(strQuery));
				sqlCommand = new MySqlCommand(strQuery, sqlConnection, sqlTransaction);               
				sqlCommand.ExecuteNonQuery();
				sqlCommand.Dispose();

				sqlCommand=sqlConnection.CreateCommand();
				sqlCommand.CommandTimeout=Constants.COMMAND_TIMEOUT;
				strQuery=Utility.ListToString(schema.SchemaLines,' ');
				Console.WriteLine(String.Format(schema.SchemaLines[0]));
				sqlCommand = new MySqlCommand(strQuery, sqlConnection, sqlTransaction);               
				int result=sqlCommand.ExecuteNonQuery();
				sqlCommand.Dispose();

				sb=new StringBuilder();
				sb.Append("ALTER TABLE ").Append(schema.TableName).Append(" DISCARD TABLESPACE;");
				strQuery=sb.ToString();
				Console.WriteLine(String.Format("{0}",strQuery));
				sqlCommand = new MySqlCommand(strQuery, sqlConnection, sqlTransaction);               
				sqlCommand.CommandTimeout=Constants.COMMAND_TIMEOUT;
				result=sqlCommand.ExecuteNonQuery();
				sqlCommand.Dispose();

				Console.WriteLine(String.Format("Copy file {0} -> {1}",pathIdbFile,pathIdbFileDestination));
				File.Copy(pathIdbFile,pathIdbFileDestination,true);

				sb=new StringBuilder();
				sb.Append("ALTER TABLE ").Append(schema.TableName).Append(" IMPORT TABLESPACE;");
				strQuery=sb.ToString();
				Console.WriteLine(String.Format("{0}",strQuery));
				sqlCommand = new MySqlCommand(strQuery, sqlConnection, sqlTransaction);               
				sqlCommand.CommandTimeout=Constants.COMMAND_TIMEOUT;
				sqlCommand.ExecuteNonQuery();
				sqlCommand.Dispose();

				try
				{
					sb=new StringBuilder();
					sb.Append("ALTER TABLE ").Append(schema.TableName).Append(" CONVERT TO CHARACTER SET ").Append(Constants.CHARACTER_SET).Append(" COLLATE ").Append(Constants.COLLATION).Append(";");
					strQuery=sb.ToString();
					Console.WriteLine(String.Format("{0}",strQuery));
					sqlCommand = new MySqlCommand(strQuery, sqlConnection, sqlTransaction);               
  				  sqlCommand.CommandTimeout=Constants.COMMAND_TIMEOUT;
					sqlCommand.ExecuteNonQuery();
					sqlCommand.Dispose();
				}
				catch(Exception exception)
				{
				  Console.WriteLine("Exception converting character set :{0}",exception.ToString());
				}

        if(schema.HasForeignKey)
				{
					sb=new StringBuilder();
					sb.Append("ALTER TABLE ").Append(schema.TableName).Append(" ADD ").Append(schema.ForeignKeyConstraint).Append(";");
					strQuery=sb.ToString();
					Console.WriteLine(String.Format("{0}",strQuery));
					sqlCommand = new MySqlCommand(strQuery, sqlConnection, sqlTransaction);               
				  sqlCommand.CommandTimeout=Constants.COMMAND_TIMEOUT;
					sqlCommand.ExecuteNonQuery();
					sqlCommand.Dispose();
				}
				sqlTransaction.Commit();
				Console.WriteLine("");
			}
			catch(Exception exception)
			{
				Console.WriteLine(String.Format("Exception:{0}",exception.ToString()));
				try{sqlTransaction.Rollback();}
				catch(Exception rollbackException)
				{
				  Console.WriteLine(String.Format("Rollback exception:{0}",rollbackException.ToString()));
				}
			}
		}
		private static bool VerifyIdbFiles(Schemas schemas,Config config)
		{
		  bool success=true;
		  foreach(Schema schema in schemas)
			{
			  String pathIdbFile=config.PathIbd+"\\"+schema.TableName+Constants.IBD_EXTENSION;;
			  Console.Write(String.Format("{0}",pathIdbFile));
				if(!File.Exists(pathIdbFile))
				{
				  Console.WriteLine("...Not found.");
					success=false;
				}
				Console.WriteLine("...Verified");
			}
			return success;
		}
		private static Schemas GetSchemas(Config config)
		{
		  Schemas schemas=new Schemas();

			try
			{
				FileStream inStream = new FileStream(config.PathSchemaFileName,FileMode.Open);
				StreamReader streamReader=new StreamReader(inStream);
				String strLine=null;

				bool inCreate=false;
				Schema schema=null;
				while(null!=(strLine=streamReader.ReadLine()))
				{
					if(strLine.StartsWith("CREATE TABLE") && !inCreate)
					{
						schema=new Schema();
						schema.TableName=Utility.BetweenString(strLine,"`","`");
						schema.SchemaLines.Add(strLine);
						inCreate=true;
					}
					else if(inCreate)
					{
//						schema.SchemaLines.Add(strLine);
						if(strLine.Contains("FOREIGN KEY"))
						{
//							schema.SchemaLines.Add(strLine);
							schema.ForeignKeyConstraint=strLine;

						  schema.HasForeignKey=true;
							String[] elements=strLine.Split(' ');
							schema.ForeignKeyTable=GetForeignKeyTable(elements);
						}
						else if(strLine.Trim().EndsWith(";"))
						{
//              schema.SchemaLines.Add(") ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci;");
             if(schema.SchemaLines[schema.SchemaLines.Count-1].EndsWith(","))
						 {
						   String line=schema.SchemaLines[schema.SchemaLines.Count-1];
							 line=line.Substring(0,line.Length-1);     // FUNNY
						   schema.SchemaLines[schema.SchemaLines.Count-1]=line;
						 }
							schema.SchemaLines.Add(strLine);
						  inCreate=false;
							schemas.Add(schema);
							schema=null;
					  }
						else
						{
							schema.SchemaLines.Add(strLine);
						}
					}
				}
				streamReader.Close();
				streamReader.Dispose();
				inStream.Close();
				inStream.Dispose();
				OrderSchemas(schemas);
				return schemas;
			}
			catch(Exception exception)
			{
			  Console.WriteLine(String.Format("Exception:{0}",exception.ToString()));
			  return null;
			}
		}
		private static Schemas OrderSchemas(Schemas schemas)
		{
		  for(int index=0;index<schemas.Count;index++)
			{
			  Schema schema=schemas[index];
				if(schema.HasForeignKey)
				{
					int foreignKeyIndex=FindSchemaLocation(schemas,schema.ForeignKeyTable);
					if(-1==foreignKeyIndex)
					{
					  Console.WriteLine(String.Format("Cannot locate schema {0}",schema.ForeignKeyTable));
						return schemas;
					}
					if(index>foreignKeyIndex)continue;
					SwapSchemaPositions(schemas,index,foreignKeyIndex);
					index=-1;
					continue;
				}
			}
			return schemas; 
		}
		private static void SwapSchemaPositions(Schemas schemas,int schemaIndex,int foreignKeySchemaIndex)
		{
		  Schema tempSchema=schemas[schemaIndex];
			schemas[schemaIndex]=schemas[foreignKeySchemaIndex];
			schemas[foreignKeySchemaIndex]=tempSchema;
		}
		private static int FindSchemaLocation(Schemas schemas,String tableName)
		{
		  for(int index=0;index<schemas.Count;index++)
			{
			  if(schemas[index].TableName.Equals(tableName))
				{
				  return index;
				}
			}
			return -1;
		}
		private static String GetForeignKeyTable(String[] elements)
		{
		  String tableName=Utility.GetElementAfter(elements,"REFERENCES");
			tableName=Utility.BetweenString(tableName,"`","`");
			return tableName;
		}

		private static Config GetConfig(CommandArgs commandArgs)
		{
		  Config config=new Config();
			config.Server=commandArgs.Get<String>("SERVER");
			config.Port=commandArgs.Get<int>("PORT");
			config.Database=commandArgs.Get<String>("DATABASE");
			config.User=commandArgs.Get<String>("USER");
			config.Password=commandArgs.Get<String>("PASSWORD");
			config.PathSchemaFileName=commandArgs.Get<String>("PATHSCHEMAFILE");
			config.PathIbd=commandArgs.Get<String>("PATHIBD");
			config.Mode=commandArgs.Get<String>("MODE");
			config.DatabaseDirectory=commandArgs.Get<String>("DATABASEDIRECTORY");
			if(commandArgs.Has("CONVERTCHARSETCOLLATION"))
			{
				String[] charsetcollation=commandArgs.Get<String>("CONVERTCHARSETCOLLATION").Split('@');
				config.CharacterSet=charsetcollation[0];
				config.Collation=charsetcollation[1];
			}
      return config;
		}
  }
}