library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use ieee.numeric_std.all;

entity Main is
    Port ( reset     : in STD_LOGIC;
           clk       : in STD_LOGIC;
           led       : out std_logic_vector (15 downto 0));
end Main;

architecture Behavioral of Main is

signal ledME    : bit_vector (7 downto 0);
signal ledMD    : bit_vector (7 downto 0);
signal count    : unsigned (22 downto 0) := (others=>'0');
signal ledzero  : unsigned (15 downto 0) := "0000000000000000";
signal enable   : std_logic := '0';
signal clk05: std_logic;
type estado is (inicio, frente, direita, esquerda, atras, low_bat);
signal prox_estado, estado_atual : estado := inicio;
signal count_action : unsigned (27 downto 0) := (others=>'0');
signal count_battery : unsigned (6 downto 0) := "0000000";
signal count_passo: integer;


begin

    -- processo de geração de clk

    -- contador de 100 ms e criacao do enable
    process(clk,reset)
    begin
        if reset='1' then
            count <= (others=>'0');
        elsif rising_edge(clk) then
            if count = "10011000100101101000000" then
                enable <= '1';
                count <= (others=>'0');
            else
                enable <= '0';
                count <= count+1;
            end if;
        end if;
    end process;

    -- processo para registrar estado --------------------------------------------------------
    process(clk,reset)
    begin
        if reset='1' then
            estado_atual <= inicio;
        elsif rising_edge(clk) then
            estado_atual <= prox_estado;

        end if;
    end process;

    -- processo para zerar os leds -----------------------------------------------------------


    -- processo da maquina de estados --------------------------------------------------------
    process (estado_atual, clk)
    begin
        case estado_atual is
        when  inicio =>
            ledMe <= (others => '0');
            ledMd <= (others => '0');
            count_passo <= 0;

        when  frente =>
            ledMe <= "00000001";
            ledMd <= "00000001";
            if count_passo = 1 then
                if count_action = "0101111101011110000100000000" then
                    prox_estado <= direita;
                    count_passo <= count_passo + 1;
                else
                    ledMe <= ledMe rol 1;
                    ledMd <= ledMd rol 1;
                end if;
            elsif count_passo= 3 then
                if count_action = "0010111110101111000010000000" then
                   prox_estado <= direita;
                   count_passo <= count_passo + 1;
                else
                    ledMe <= ledMe rol 1;
                    ledMd <= ledMd rol 1;
                end if;
            else
                if count_action = "0010111110101111000010000000" then
                   prox_estado <= esquerda;
                   count_passo <= count_passo + 1;
                else
                   ledMe <= ledMe rol 1;
                   ledMd <= ledMd rol 1;
                end if;
            end if;

        when  direita =>
            ledMe <= "10000000";
            ledMd <= "00000001";
            if count_passo = 2 then
                if count_action = "0101111101011110000100000000" then
                    prox_estado <= frente;
                    count_passo <= count_passo + 1;
                else
                    ledMe <= ledMe ror 1;
                    ledMd <= ledMd rol 1;
                end if;
            else
                if count_action = "0101111101011110000100000000" then
                    prox_estado <= atras;
                    count_passo <= count_passo + 1;
                else
                    ledMe <= ledMe ror 1;
                    ledMd <= ledMd rol 1;
                end if;

            end if;

        when  esquerda =>
            ledMe <= "00000001";
            ledMd <= "10000000";
            if count_passo = 4 then
                if count_action = "0101111101011110000100000000" then
                    prox_estado <= frente;
                    count_passo <= count_passo + 1;
                else
                    ledMe <= ledMe rol 1;
                    ledMd <= ledMd ror 1;
                end if;
            else
                if count_action = "0101111101011110000100000000" then
                    prox_estado <= atras;
                    count_passo <= count_passo + 1;
                else
                    ledMe <= ledMe rol 1;
                    ledMd <= ledMd ror 1;
                end if;
            end if;

        when  atras =>
            ledMe <= "10000000";
            ledMd <= "10000000";
            if count_passo = 7 then
                if count_action = "1000111100001101000110000000" then
                    prox_estado <= esquerda;
                    count_passo <= count_passo + 1;
                else
                    ledMe <= ledMe ror 1;
                    ledMd <= ledMd ror 1;
                end if;
            else
                if count_action = "1011111010111100001000000000" then
                    prox_estado <= low_bat;
                    count_passo <= count_passo + 1;
                else
                    ledMe <= ledMe ror 1;
                    ledMd <= ledMd ror 1;
                end if;
            end if;
        when  low_bat =>
            ledMe <= (others => '0');
            ledMd <= (others => '0');
            if rising_edge(clk05) then
                ledMe <= not ledME;
                ledMd <= not ledMd;
            else
               ledMe <= ledME;
               ledMd <= ledMd;
            end if;
        end case;
    end process;

    led (15 downto 8) <= to_stdlogicvector (ledME);
    led (7 downto 0)  <= to_stdlogicvector (ledMD);

end Behavioral;