--This program reads the data.dat input file. It stores
--the read line characters (one by one) into a character
--variable. It processes line by line of the input file
--until EOF is encountered.

library std;
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
use IEEE.numeric_std.all;
use Std.Standard.all;
--use STD_LOGIC_TEXTIO.ALL;
use std.textio.all;

entity read_file is
    Port ( Clk : in  STD_LOGIC;
           --Rst : in  STD_LOGIC;
           Go : in  STD_LOGIC;
			  filenum : in integer range 7 downto 0;
			  Ain : in  STD_LOGIC_VECTOR (7 downto 0);
           Wr : out  STD_LOGIC;
           A : out  STD_LOGIC_VECTOR (7 downto 0);
           D : out  STD_LOGIC_VECTOR (7 downto 0);
			  Done : out STD_LOGIC);
end read_file;
			  
architecture stimuli of read_file is

	component pulser is
		Port ( Clk : in  STD_LOGIC;
			  D   : in  STD_LOGIC;
           Q   : out  STD_LOGIC);
	end component;

	signal En : STD_LOGIC := '0';
	signal iEn : STD_LOGIC;
	signal A_int : STD_LOGIC_VECTOR (7 downto 0);

begin

	read_input_file: process (Clk,Go,En)
			variable inline:line;
			variable charvar1:character; variable var1 : std_logic_vector (3 downto 0);
			variable charvar2:character; variable var2 : std_logic_vector (3 downto 0);
			variable end_of_line:boolean;
			
			file myfile : text;-- is "InPacket.dat";
			variable myfilename : string (1 to 16);
			variable file_status : file_open_status;
	begin

		case filenum is
			when 1 => myfilename := "InPacket1_R'.dat";
			when 2 => myfilename := "InPacket2_Q_.dat";
			when 3 => myfilename := "InPacket3_P_.dat";
			when others => myfilename := "InPacket4___.dat";
		end case;
	
		if falling_edge(En) then file_close(myfile); end if;
		if rising_edge(Go) then 
			file_open(file_status, myfile, myfilename, read_mode);
			if (file_status=open_ok) then
				En <= '1';
			end if;
		end if;


		if (Go='1') then
			--En <= '1';
			Wr <= '0';
			A_int <= Ain - X"01";

		else
--			A_int <= A_int;
			if (En='1') then
				if endfile(myfile) then
					Wr <= '0';
					En <= '0';
				else
					En <= En;
					if (rising_edge(Clk) and En='1') then
						readline(myfile,inline);
						read(inline,charvar1);
						read(inline,charvar2,end_of_line);
						--end_of_line is EOLN boolean flag
	--					while end_of_line loop
	--						read(inline,charvar,end_of_line);
	--					end loop;
						A_int <= A_int + X"01";
						Wr <= '1';
						--D <= conv_std_logic_vector(character'pos(charvar1),8);
						case charvar1 is
							when '0' => D(7 downto 4) <=   x"0";
							when '1' => D(7 downto 4) <=   x"1";
							when '2' => D(7 downto 4) <=   x"2";
							when '3' => D(7 downto 4) <=   x"3";
							when '4' => D(7 downto 4) <=   x"4";
							when '5' => D(7 downto 4) <=   x"5";
							when '6' => D(7 downto 4) <=   x"6";
							when '7' => D(7 downto 4) <=   x"7";
							when '8' => D(7 downto 4) <=   x"8";
							when '9' => D(7 downto 4) <=   x"9";
							when 'A' => D(7 downto 4) <=   x"A";
							when 'B' => D(7 downto 4) <=   x"B";
							when 'C' => D(7 downto 4) <=   x"C";
							when 'D' => D(7 downto 4) <=   x"D";
							when 'E' => D(7 downto 4) <=   x"E";
							when 'F' => D(7 downto 4) <=   x"F";
							when others => D(7 downto 4) <= x"0";
						end case;
						case charvar2 is
							when '0' => D(3 downto 0) <=   x"0";
							when '1' => D(3 downto 0) <=   x"1";
							when '2' => D(3 downto 0) <=   x"2";
							when '3' => D(3 downto 0) <=   x"3";
							when '4' => D(3 downto 0) <=   x"4";
							when '5' => D(3 downto 0) <=   x"5";
							when '6' => D(3 downto 0) <=   x"6";
							when '7' => D(3 downto 0) <=   x"7";
							when '8' => D(3 downto 0) <=   x"8";
							when '9' => D(3 downto 0) <=   x"9";
							when 'A' => D(3 downto 0) <=   x"A";
							when 'B' => D(3 downto 0) <=   x"B";
							when 'C' => D(3 downto 0) <=   x"C";
							when 'D' => D(3 downto 0) <=   x"D";
							when 'E' => D(3 downto 0) <=   x"E";
							when 'F' => D(3 downto 0) <=   x"F";
							when others => D(3 downto 0) <= x"0";
						end case;
						
					end if;
				end if;
			else
				A_int <= A_int;
			end if;		
		end if;
	end process read_input_file;

	iEn <= not En;
	u1: pulser port map (Clk, iEn, Done);
	A <= A_int;

end stimuli;