-- Interactive Audio Manipulation Processor
--
-- file: audio.vhd
-- status: not compiled
--
-- author: Stephen Tang
--
-- A wrapper entity for the audio functionality. Currently, this entity
-- only converts the onscreen X and Y coordinates of the sound source to
-- a coarser-grained set of coordinates.

library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_arith.all;
use ieee.std_logic_unsigned.all;

library work;
use work.Constants_Pkg.all;

entity audio2 is
  port (
    clock: in std_logic;
    screenX: in std_logic_vector(DISPLAY_X-1 downto 0);
    screenY: in std_logic_vector(DISPLAY_Y-1-4 downto 0);
    locationX: out std_logic_vector(SOURCE_WIDTH-1 downto 0);
    locationY: out std_logic_vector(SOURCE_WIDTH-1 downto 0)
  );
end audio2;

architecture wrapper of audio2 is
begin
  ConvertCoordinates: process(clock)
    variable count1,count2: std_logic_vector(DISPLAY_X-1-4 downto 0);
    variable countA,countB: std_logic_vector(DISPLAY_X-1 downto 0);
    variable val,newLocation: std_logic_vector(SOURCE_WIDTH-1 downto 0);
    variable NoRemainder: std_logic_vector(1 downto 0);
  begin
    if rising_edge(clock) then
      -- convert X value; see end of file for more info
      countB := "0000000000";
      val := "0000";
      NoRemainder := "00";
      for i in 1 to MAX_SOUND loop
        countA := countB;
        countB := countB + X"2B";  -- add 42+1
        val := val + "0001";
	      NoRemainder := NoRemainder + '1';
	      if (NoRemainder = "11") then
	        countB := countB - '1';
	        NoRemainder := "00";
	      end if;
	      if (screenX >= countA) and (screenX < countB) then
	        newLocation := val;
	        i := MAX_SOUND;
	      end if;
      end loop;
      locationX <= newLocation;
      
      -- convert Y value
      count2 := "000000";
      val := "0000";
      for i in 1 to MAX_SOUND loop
        count1 := count2;
        count2 := count2 + X"2";  -- add 32
        val := val + "0001";
	      if (screenY >= count1) and (screenY < count2) then
	        newLocation := val;
	      end if;
      end loop;
      locationY <= newLocation;
    end if;
  end process ConvertCoordinates;
end;