`timescale 1ns / 1ps
//////////////////////////////////////////////////////////////////////////////////
// Company: 
// Engineer: 
// 
// Create Date:    11:35:04 11/22/2013 
// Design Name: 
// Module Name:    Run_before_Decoder 
// Project Name: 
// Target Devices: 
// Tool versions: 
// Description: 
//
// Dependencies: 
//
// Revision: 
// Revision 0.01 - File Created
// Additional Comments: 
//
//////////////////////////////////////////////////////////////////////////////////
module run_before_decoder(
	Code,//码字
	Clk,//时钟信号
	Rst,//复位信号
	Sig_start,//触发信号
	Sig_done,//模块完成信号
    Sig_code_fill_done,//码字更新完成信号
    Sig_code_fill,//码字长度不足，发送信号更新Code
	TotalCoeff,//输入TotalCoeff值
	TotalZero,//输入TotalZero值
	RunBefore_code_length,//返回runbefore码字长度
	Level_0,//按从高频到低频顺序输入level
	Level_1,
	Level_2,
	Level_3,
	Level_4,
	Level_5,
	Level_6,
	Level_7,
	Level_8,
	Level_9,
	Level_10,
	Level_11,
	Level_12,
	Level_13,
	Level_14,
	Level_15,
	
	Level_0_de,//输出解码后的4x4块值，从高频到低频。
	Level_1_de,
	Level_2_de,
	Level_3_de,
	Level_4_de,
	Level_5_de,
	Level_6_de,
	Level_7_de,
	Level_8_de,
	Level_9_de,
	Level_10_de,
	Level_11_de,
	Level_12_de,
	Level_13_de,
	Level_14_de,
	Level_15_de,
	//DEBUG
	level_cnt_t,
	CodeLength
	//
    );
    parameter Level_Length = 16;
    input Clk,Rst;
    input Sig_start;
    input Sig_code_fill_done;
    input [63:0]Code;
    input [4:0] TotalCoeff;
    input [3:0] TotalZero;

    input [Level_Length -1:0]Level_0;
    input [Level_Length -1:0]Level_1;
    input [Level_Length -1:0]Level_2;
    input [Level_Length -1:0]Level_3;
    input [Level_Length -1:0]Level_4;
    input [Level_Length -1:0]Level_5;
    input [Level_Length -1:0]Level_6;
    input [Level_Length -1:0]Level_7;
    input [Level_Length -1:0]Level_8;
    input [Level_Length -1:0]Level_9;
    input [Level_Length -1:0]Level_10;
    input [Level_Length -1:0]Level_11;
    input [Level_Length -1:0]Level_12;
    input [Level_Length -1:0]Level_13;
    input [Level_Length -1:0]Level_14;
    input [Level_Length -1:0]Level_15;

    output Sig_done;
    output Sig_code_fill;
    output [7:0]RunBefore_code_length;
    output [Level_Length -1:0]Level_0_de;
    output [Level_Length -1:0]Level_1_de;
    output [Level_Length -1:0]Level_2_de;
    output [Level_Length -1:0]Level_3_de;
    output [Level_Length -1:0]Level_4_de;
    output [Level_Length -1:0]Level_5_de;
    output [Level_Length -1:0]Level_6_de;
    output [Level_Length -1:0]Level_7_de;
    output [Level_Length -1:0]Level_8_de;
    output [Level_Length -1:0]Level_9_de;
    output [Level_Length -1:0]Level_10_de;
    output [Level_Length -1:0]Level_11_de;
    output [Level_Length -1:0]Level_12_de;
    output [Level_Length -1:0]Level_13_de;
    output [Level_Length -1:0]Level_14_de;
    output [Level_Length -1:0]Level_15_de;
    //DEBUG
    output [3:0] level_cnt_t;
    output [3:0] CodeLength;
    //
    wire [Level_Length -1:0]Level_0_de;
    wire [Level_Length -1:0]Level_1_de;
    wire [Level_Length -1:0]Level_2_de;
    wire [Level_Length -1:0]Level_3_de;
    wire [Level_Length -1:0]Level_4_de;
    wire [Level_Length -1:0]Level_5_de;
    wire [Level_Length -1:0]Level_6_de;
    wire [Level_Length -1:0]Level_7_de;
    wire [Level_Length -1:0]Level_8_de;
    wire [Level_Length -1:0]Level_9_de;
    wire [Level_Length -1:0]Level_10_de;
    wire [Level_Length -1:0]Level_11_de;
    wire [Level_Length -1:0]Level_12_de;
    wire [Level_Length -1:0]Level_13_de;
    wire [Level_Length -1:0]Level_14_de;
    wire [Level_Length -1:0]Level_15_de;

    reg [63:0]Code_t;
    reg [7:0] Bound;
    reg Sig_code_fill;
    wire [63:0] Code_spliced;
    wire [63:0] Code;
    reg Sig_done;
    reg [7:0]RunBefore_code_length;
    reg [2:0] cnt;
    //reg [3:0] residue;//=TotalCoeff+TotalZero;
    reg [3:0] level_cnt_t;
    reg [3:0] ZerosLeft;
    wire [3:0] RunBefore;
    reg [3:0] RunBefore_t;
    reg [Level_Length -1:0] Level_value;
    //reg [3:0] Level_num;
    reg Sig_level_write;
    reg Sig_level_clr;
    reg [4:0] TotalCoeff_t;
    wire [3:0] CodeLength;
    
    ZerosLeft_lut zerosLeft_lut (
        .Code(Code_t[15:0]), 
        .ZerosLeft(ZerosLeft), 
        .RunBefore(RunBefore), 
        .CodeLength(CodeLength)
        );
         
    Level_Buffer level_Buffer (
        .Clk(Clk), 
        .Rst(Rst), 
        .Sig_level_write(Sig_level_write), 
        .Sig_level_clr(Sig_level_clr),
        .Level_num(level_cnt_t), 
        .Level_value(Level_value), 
        .Level_0(Level_0_de), 
        .Level_1(Level_1_de), 
        .Level_2(Level_2_de), 
        .Level_3(Level_3_de), 
        .Level_4(Level_4_de), 
        .Level_5(Level_5_de), 
        .Level_6(Level_6_de), 
        .Level_7(Level_7_de), 
        .Level_8(Level_8_de), 
        .Level_9(Level_9_de), 
        .Level_10(Level_10_de), 
        .Level_11(Level_11_de), 
        .Level_12(Level_12_de), 
        .Level_13(Level_13_de), 
        .Level_14(Level_14_de), 
        .Level_15(Level_15_de)
        );
        
    code_splice Code_splice_for_runbefore_decoder (
        .Code_A(Code_t), 
        .Code_B(Code), 
        .Bound(Bound), 
        .Code_spliced(Code_spliced)
        );
        
    always @(posedge Clk or negedge Rst) begin
        if(!Rst) begin
            cnt <= 0;
            Code_t <= 0;
            RunBefore_code_length <=0;
            Sig_done <= 0;
            ZerosLeft <= 0;
            level_cnt_t <= 0;
            Sig_level_write <= 0;
            TotalCoeff_t <= 0;
            RunBefore_t <=0 ;
            Sig_code_fill <= 0;
        end
        else begin
            case(cnt)
            0:begin
                if(Sig_start) begin
                /*
                    Level_0_de <= 0;
                    Level_1_de <= 0;
                    Level_2_de <= 0;
                    Level_3_de <= 0;
                    Level_4_de <= 0;
                    Level_5_de <= 0;
                    Level_6_de <= 0;
                    Level_7_de <= 0;
                    Level_8_de <= 0;
                    Level_9_de <= 0;
                    Level_10_de <= 0;
                    Level_11_de <= 0;
                    Level_12_de <= 0;
                    Level_13_de <= 0;
                    Level_14_de <= 0;
                    Level_15_de <= 0;*/
                    Code_t <= Code;
                    RunBefore_code_length <=0;
                    level_cnt_t <= 16-(TotalCoeff+TotalZero);
                    TotalCoeff_t <= 0;
                    RunBefore_t <= 0;
                    ZerosLeft <= TotalZero;
                    Sig_level_write <= 0;
                    Sig_level_clr <= 1;
                    Sig_done <= 0;
                    Sig_code_fill <= 0;
                    cnt <= 1;
                end
                else begin
                    Sig_level_clr <= 0;
                    Sig_level_write <= 0;
                    cnt<=0;
                end
            end
            1:begin
                //Level_num <= level_cnt;
                Sig_level_write <= 1;
                Sig_level_clr <= 0;
                ZerosLeft <= ZerosLeft-RunBefore_t;
                TotalCoeff_t <= TotalCoeff_t+1;
                if(TotalCoeff_t==0)begin
                    level_cnt_t <= 16-(TotalCoeff+TotalZero);
                end
                else begin
                    level_cnt_t <= level_cnt_t+RunBefore_t+1;
                end	
                cnt <= cnt + 1;
                case(TotalCoeff_t)
                0:begin
                    Level_value <= Level_0;
                end
                1:begin
                    Level_value <= Level_1;
                end
                2:begin
                    Level_value <= Level_2;
                end
                3:begin
                    Level_value <= Level_3;
                end
                4:begin
                    Level_value <= Level_4;
                end
                5:begin
                    Level_value <= Level_5;
                end
                6:begin
                    Level_value <= Level_6;
                end
                7:begin
                    Level_value <= Level_7;
                end
                8:begin
                    Level_value <= Level_8;
                end
                9:begin
                    Level_value <= Level_9;
                end
                10:begin
                    Level_value <= Level_10;
                end
                11:begin
                    Level_value <= Level_11;
                end
                12:begin
                    Level_value <= Level_12;
                end
                13:begin
                    Level_value <= Level_13;
                end
                14:begin
                    Level_value <= Level_14;
                end
                15:begin
                    Level_value <= Level_15;
                end
                endcase
            end
            2:begin
                Sig_level_write <= 0;
                if(ZerosLeft<=0) begin
                    RunBefore_code_length <= RunBefore_code_length;
                    RunBefore_t <= 0;
                    if(TotalCoeff_t==TotalCoeff) begin
                        cnt <= cnt+1;
                        Sig_done <= 1;
                    end	
                    else begin
                        cnt <= 1;
                    end  
                end
                else begin
                    Code_t <= Code_t>>CodeLength;
                    RunBefore_t <= RunBefore;
                    if(TotalCoeff_t==TotalCoeff) begin
                        cnt <= cnt+1;
                        Sig_done <= 1;
                        RunBefore_code_length <= RunBefore_code_length;
                    end
                    else begin
                        cnt <= 1;
                        RunBefore_code_length <= RunBefore_code_length+CodeLength;
                        if((RunBefore_code_length+CodeLength)<=53) begin //runbefore码字最长长度为11,53 = 64 - 11，
                            Bound <= (RunBefore_code_length+CodeLength);
                        end 
                        else begin
                            Sig_code_fill <= 1;
                            cnt <= 3'd4;
                        end
                    end				
                end	 
            end
            3:begin
                Sig_done <= 0;
                cnt <= 0;
            end
            4:begin
                Sig_code_fill <= 0;
                if(Sig_code_fill_done==1'b1) begin
                    Code_t <= Code_spliced;
                    Bound <= 0;
                    cnt <= 1;
                end
                else begin
                    cnt <= 4;
                end
            end
            default:begin
                cnt <= 0;
            end
            endcase
        end
    end

endmodule