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

package MINE is
  type INTEGER_MATRIX is array (NATURAL RANGE <>, NATURAL RANGE <>) of integer;
  procedure addM (L, R : in INTEGER_MATRIX; RESULT : out INTEGER_MATRIX);
end MINE;
package BODY MINE is
  procedure addM (L, R : in INTEGER_MATRIX; RESULT : out INTEGER_MATRIX) is
    alias new_l : INTEGER_MATRIX(L'LENGTH(1) - 1 downto 0, 
                                 L'LENGTH(2) - 1 downto 0) is L;
    alias new_r : INTEGER_MATRIX(R'LENGTH - 1 downto 0) is R;
  begin
    if (L'LENGTH /= R'LENGTH) then
      report "Ranges of operands are not the same"
      severity WARNING;
    return integer'LEFT;
    end if;
    for I in new_l'RANGE loop
      temp := temp + new_l(I)*new_r(I);
    end loop;
    return TEMP;
  end DOT_PRODUCT;
end MINE;

package body MINE is
  function SEARCH(VECTOR, SUBVECTOR : std_logic_vector) return integer is
    variable POSITION : integer;
    variable FOUND : boolean := FALSE;
  begin
    POSITION := -1;
    if (VECTOR'length < SUBVECTOR'length) then
      report "Incorrect usage of SEARCH function"
      severity error;
      return POSITION;
    end if;
    for I in VECTOR'length - 1 downto SUBVECTOR'length - 1 loop
      if not FOUND then
        if (VECTOR(I downto I - (SUBVECTOR'length -1)) = SUBVECTOR) then
          POSITION := I;
          FOUND := TRUE;
        end if;
      end if;
    end loop;
    return POSITION;
  end SEARCH;
end MINE;


architecture BEHAV of ELEVATOR_CONTROL is
  type STATE_TYPE is (F12, F22, F21, F11);
  signal CURRENT_STATE, NEXT_STATE : STATE_TYPE;
begin
  process (FB1, CALL1, FB2, CALL2, FS1, FS2, DC,
           N1, N2, CURRENT_STATE)
  begin
    if (CURRENT_STATE = F12) then
      if (FS2 = '0') then
        UP <= '1';
        NEXT_STATE <= F12;
      else
        R2 <= '1';
        DO <= '1';
        NEXT_STATE <= F22;
      end if;
    elsif (CURRENT_STATE = F22) then
      NEXT_STATE <= F22;
      if (N2 = '1') then
        R2 <= '1';
        DO <= '1';
      elsif (N1 = '1') then
        if (DC = '1') then
          DOWN <= '1';
          NEXT_STATE <= F21;
        end if;
      end if;
    elsif (CURRENT_STATE = F21) then
      if (FS1 = '1') then
        R1 <= '1';
        DO <= '1';
        NEXT_STATE <= F11;
      else
        DOWN <= '1';
        NEXT_STATE <= F21;
      end if;
    elsif (CURRENT_STATE = F11) then
      NEXT_STATE <= F11;
        if (N1 = '1') then
          R1 <= '1';
          DO <= '1';
        elsif (N2 = '1') then
          if (DC = '1') then
            UP <= '1';
            NEXT_STATE <= F12;
          end if;
        end if;
    end if;
  end process;
  process (CLK)
  begin
    if (CLK = '1' and CLK'event) then
      CURRENT_STATE <= NEXT_STATE;
    end if;
  end process;
end BEHAV;