`timescale 1ns / 1ps

module generator_tb;

    parameter DATA_WIDTH = 14;
    parameter CLK_PERIOD = 16;

    logic clk;
    logic rst;
    logic start;

    logic [31:0] pulse_width;
    logic [31:0] pulse_period;
    logic [DATA_WIDTH-1:0] pulse_height;
    logic [15:0] pulse_num;

    logic pulse;
    logic [DATA_WIDTH-1:0] pulse_height_out;

    // DUT
    generator #(
        .DATA_WIDTH(DATA_WIDTH)
    ) dut (
        .clk_in(clk),
        .rst(rst),
        .start(start),
        .pulse_width(pulse_width),
        .pulse_period(pulse_period),
        .pulse_height(pulse_height),
        .pulse_num(pulse_num),
        .pulse(pulse),
        .pulse_height_out(pulse_height_out)
    );

    // Clock
    initial begin
        clk = 0;
        forever #(CLK_PERIOD/2) clk = ~clk;
    end

    initial begin
        $display("\n=== GENERATOR TEST ===\n");

        rst = 1;
        start = 0;

        pulse_width  = 0;
        pulse_period = 0;
        pulse_height = 0;
        pulse_num    = 0;

        repeat(5) @(posedge clk);
        rst = 0;

        // --- Test 1 ---
        // 3 clk 1, 5 clk 0,  4 pulses
       repeat(2) @(posedge clk);
        pulse_width  = 3;
        pulse_period = 8;
        pulse_num    = 4;
        pulse_height = 14'h3FF;
        start = 1;

       repeat(1) @(posedge clk);
        start = 0;

        repeat(50) @(posedge clk);

        // --- Test 2 ---
        $display("\n--- SECOND RUN ---\n");

        @(posedge clk);
        pulse_width  = 2;
        pulse_period = 5;
        pulse_num    = 3;
        pulse_height = 14'h155;
        start = 1;

        @(posedge clk);
        start = 0;

        repeat(40) @(posedge clk);
        
         pulse_width  = 3;
        pulse_period = 8;
        pulse_num    = 4;
        pulse_height = 14'h3FF;
        start = 1;

       repeat(1) @(posedge clk);
        start = 0;

        repeat(50) @(posedge clk);

        $display("\n=== TEST FINISHED ===");
        $finish;
    end

    // Display
    always @(posedge clk) begin
        $display("t=%0t | pulse=%0b | height=%h",
                  $time, pulse, pulse_height_out);
    end

endmodule