#include "StdAfx.h"
#include "MainForm.h"

#include "inp.h"
#include "out.h"
#include "lex.h"
#include "code1.h"
#include "expr1.h"
#include "stat1.h"

using namespace System::IO;
using namespace System::Windows;

Prekl::MainForm ^ getMainForm () { return Prekl::MainForm::win; }

namespace Prekl
{
	ref class CompilerException: System::Exception
	{
	   public:
		   CompilerException (String ^ txt) :
			   Exception (txt)
		   { }
	};

	std::string SysToStd (String ^ txt)
	{
		int len = txt->Length;
		char * p = new char [len+1];
		for (int i = 0; i < len; i ++)
			p[i] = char (txt[i]);
		p[len] = 0;
		std::string s (p);
		delete [] p;
		return s;
	}

	String ^ StdToSys (std::string s)
	{
		String ^ txt = gcnew String (s.c_str ());
		return txt;
	}

	String ^ IntToStr (int n)
	{
	   return "" + n;
	}
			
    /* Source Text */
	 
	std::string MainForm::GetInpLine (int line_num)
	{
		String ^ txt = "";
		if (line_num <= inputArea->Lines->Length)
		   txt = inputArea->Lines [line_num-1];
		else
		   txt = "\0";
		return SysToStd (txt);
	}

	std::string MainForm::GetInpText ()
	{
		String ^ txt = inputArea->Text;
		return SysToStd (txt);
	}

	/* Output Text */

	void MainForm::ClearOutLines ()
	{
		outputArea->Clear ();
	}

	void MainForm::ShowOutLine (std::string txt)
	{
		txt = txt;
		outputArea->AppendText (StdToSys (txt) + "\r\n");
	}

	/* Status Bar */

    void MainForm::SetStatus (String  ^txt)
	{
        statusLabel->Text = txt;
	}

	/* Show Error */

    void MainForm::ShowError (std::string txt)
	{
	   CloseInp (); /* uzavri vstup a vystup */
	   CloseOut ();

	   String ^ s = StdToSys (txt);

	   SetStatus ("Line: " + IntToStr (InpLineNum) + " " +
				  "Col: " + IntToStr (InpColNum) + " " +
				  "Error: " + s);

	   inputArea->SelectionStart = InpPos; /* pozice kurzoru ve vstupnim okenku */
	   inputArea->SelectionLength = 1;

	   MessageBox::Show
			 ( s,
               "Error", 
			   MessageBoxButtons::OK,
			   MessageBoxIcon::Error );

	   throw gcnew CompilerException (s); /* skok zpet do funkce Compile */
	}

	/* Compile */

    static bool IsIdent (char * id)
    {
	   return sy==IDENT && 
		      strcmp (IdentVal, id) == 0;
    }

    static void CheckIdent (char * id)
    {
       if (IsIdent (id))
		   NextSymbol ();
	   else
	   {
		   char msg [200] = "Identier expected: ";
		   stradd (msg, sizeof (msg), id);
		   Error (msg);
	   }
    }

	using namespace std;

    void PutString (string txt)
	{
        PutStr ((char *)txt.c_str ());
	}

    static string ReadString ()
    {
		char * result = "";
		if (sy == STR)
		{
			result = StrVal;
			NextSymbol ();
		}
		else Error ("String expected");
		return result;
	}

    static string ReadIdent ()
    {
		char * result = "";
		if (sy == IDENT)
		{
			result = IdentVal;
			NextSymbol ();
		}
		else Error ("Identifier expected");
		return result;
	}

    static string ReadNumber ()
    {
		char * result = "";
		if (sy == NUM)
		{
			result = NumVal;
			NextSymbol ();
		}
		else Error ("(Integer) number expected");
		return result;
	}

	void expr ();

	void simple_expr ()
	{
        Indent ();
		if (sy == IDENT)
          { PutString (ReadIdent ()); PutEol (); }
		else if (sy == NUM)
          { PutString (ReadNumber ()); PutEol (); }
		else if (sy == LPAR)
        {
           // PutStr ("("); PutEol ();
           NextSymbol (); /* preskoc ( */
           expr ();
           CheckSymbol (RPAR); /* ) */
           // PutStr (")"); PutEol ();
        }
		else 
           Error ("Simple expression expected");
        Unindent ();
	}

    /*
	void mul_expr ()
	{
        Indent ();
		simple_expr ();
		while (sy == ASTERISK || sy == SLASH)
		{
            if (sy == ASTERISK) PutStr ("*"); else PutStr ("/");
            PutEol ();
			NextSymbol ();
   		    simple_expr ();
		}
        Unindent ();
	}
    */

	void mul_expr ()
	{
        Indent ();
		simple_expr ();
		if (sy == ASTERISK || sy == SLASH)
		{
            if (sy == ASTERISK) PutStr ("*"); else PutStr ("/");
            PutEol ();
			NextSymbol ();
   		    mul_expr ();
		}
        Unindent ();
	}

	void expr ()
	{
        Indent ();
		mul_expr ();
		while (sy == PLUS || sy == MINUS)
		{
            if (sy == PLUS) PutStr ("+"); else PutStr ("/");
            PutEol ();
			NextSymbol ();
   		    mul_expr ();
		}
        Unindent ();
	}

	void let ()
	{
		CheckIdent ("LET");
		string name = ReadIdent ();
		CheckSymbol (ASSIGN);
        PutString ("LET " + name + " = ");
        PutEol ();
		expr ();
		CheckSymbol (SEMICOLON);
		PutEol ();
	}

	void item ()
	{
		CheckIdent ("ITEM");
		string item_name = ReadString ();
		string command_name = "";
		if (IsIdent ("COMMAND"))
		{
			NextSymbol ();
   	        command_name = ReadIdent ();
		}

		PutStr ("item ");
		PutString (item_name);
		PutStr (" with command ");
		PutString (command_name);
		PutEol ();

		CheckSymbol (SEMICOLON);
	}

	void menu ()
	{
		CheckIdent ("MENU");
		string name = "";
		if (sy == IDENT)
			name = ReadIdent ();
		else if (sy == STR)
			name = ReadString ();

		PutStr ("menu ");
		PutString (name);
		PutEol ();
		Indent ();
		CheckSymbol (LBRACE);
        
        while (sy!=RBRACE)
		{
			if (IsIdent ("MENU")) menu ();
			else if (IsIdent ("ITEM")) item ();
			else Error ("Unknown menu item");
		}

		CheckSymbol (RBRACE);
		Unindent ();
		PutStr ("end of menu");
		PutEol ();
	}

	void MainForm::Compile ()
	{
	   try
	   {
		  OpenInp ();  /* otevri vstupni a vystupni text */
		  OpenOut ();
		  InitLex ();  /* inicializace modulu Lex, precteni prvniho symbolu */
		  init_labels ();

		  while (sy!=EOS)
		  {
			  if (IsIdent ("MENU"))  menu ();
			  else if (IsIdent ("LET")) let ();
			  else Error ("Unknown statement");
		  }

		  CloseInp (); /* uzavri vstupni a vystupni text */
		  CloseOut ();
		  SetStatus ("O.K."); /* stavova radka */

		  outputArea->SelectionStart = 0; /* zobraz zacatek textu */
          outputArea->SelectionLength = 1;
		  outputArea->ScrollToCaret ();
	   }
	   catch (CompilerException ^ e)
	   {
		  /* nic - informace o chybe jiz zobrazila funkce ShowError */
	   }
	}

	/* Read File */

    void MainForm::Read (String ^ file_name)
	{
		try
		{
			StreamReader ^ f = gcnew StreamReader (file_name);
			inputArea->Text = f->ReadToEnd ();
			f->Close ();
		}
		catch (FileNotFoundException ^ e)
		{ 
			SetStatus (e->Message);
		}
		inputArea->DeselectAll ();
	}

	/* Open File */

    void MainForm::openMenuItem_Click (System::Object^  sender, System::EventArgs^  e) 
	{
		if (openFileDialog->ShowDialog () == System::Windows::Forms::DialogResult::OK)
		{
			StreamReader ^ f = gcnew StreamReader (openFileDialog->FileName);
			inputArea->Text = f->ReadToEnd ();
			f->Close ();
   		    inputArea->DeselectAll ();
		}
	}
		 
	/* Save File */

    void MainForm::saveMenuItem_Click (System::Object^  sender, System::EventArgs^  e) 
	{
		if (saveFileDialog->ShowDialog () == Forms::DialogResult::OK)
		{
			StreamWriter ^ f = gcnew StreamWriter (saveFileDialog->FileName);
			f->Write (inputArea->Text);
			f->Close ();
		}
		 
	}

	/* Change Font */

	void MainForm::fontMenuItem_Click(System::Object^  sender, System::EventArgs^  e)
	{
  	    fontDialog->Font = inputArea->Font;
		if (fontDialog->ShowDialog () == Forms::DialogResult::OK)
		{
			inputArea->Font = fontDialog->Font;
			outputArea->Font = fontDialog->Font;
		}
	}

} // end of namespace