// S3C Manifold FPGA Implementation
// Derived from Lean: Semantics/S3C.lean
// Target: Gowin GW1NR-9 (Tang Nano 9K)
// Q16.16 fixed-point arithmetic
// Implements genus-3 topological manifold for audio processing

`timescale 1ns / 1ps

`include "s3c_core.v"

// ═══════════════════════════════════════════════════════════════════════════
// S3C 3-Handle Manifold
// Maps audio sample to 3-handle manifold structure
// ═══════════════════════════════════════════════════════════════════════════
module s3c_manifold_handle (
    input  wire [15:0] sample,
    output wire [15:0] handleK,     // Coarse handle (amplitude envelope)
    output wire [15:0] handleA,     // Medium handle (spectral content)
    output wire [15:0] handleB      // Fine handle (phase information)
);
    wire [15:0] k, a, b;
    wire [31:0] mass;
    wire [15:0] width;
    
    s3c_shell_decomposition shell_inst (
        .n(sample),
        .k(k),
        .a(a),
        .b(b),
        .mass(mass),
        .width(width)
    );
    
    assign handleK = k;
    assign handleA = a;
    assign handleB = b;
endmodule

// ═══════════════════════════════════════════════════════════════════════════
// S3C Audio Processing Pipeline
// Complete S3C manifold processing for audio samples
// ═══════════════════════════════════════════════════════════════════════════
module s3c_audio_processor (
    input  wire        clk,
    input  wire        rst_n,
    input  wire [15:0] audio_sample,  // Unsigned 16-bit audio sample
    output reg  [15:0] handleK,
    output reg  [15:0] handleA,
    output reg  [15:0] handleB,
    output reg  [31:0] massResonance,
    output reg  [31:0] mirrorResonance,
    output reg  [31:0] spectralCoupling,
    output reg  [31:0] jScore,
    output reg         emit
);
    // Pipeline Stage 1: Manifold handles
    wire [15:0] handleK_stage1, handleA_stage1, handleB_stage1;
    reg [15:0] handleK_stage1_reg, handleA_stage1_reg, handleB_stage1_reg;
    
    s3c_manifold_handle manifold_inst (
        .sample(audio_sample),
        .handleK(handleK_stage1),
        .handleA(handleA_stage1),
        .handleB(handleB_stage1)
    );
    
    always @(posedge clk or negedge rst_n) begin
        if (!rst_n) begin
            handleK_stage1_reg <= 16'd0;
            handleA_stage1_reg <= 16'd0;
            handleB_stage1_reg <= 16'd0;
        end else begin
            handleK_stage1_reg <= handleK_stage1;
            handleA_stage1_reg <= handleA_stage1;
            handleB_stage1_reg <= handleB_stage1;
        end
    end
    
    // Pipeline Stage 2: Contact detection + J-score
    wire kappaA_stage2, kappaB_stage2, kappaC_stage2;
    wire [31:0] massResonance_stage2, mirrorResonance_stage2, spectralCoupling_stage2, jScore_stage2;
    reg kappaA_stage2_reg, kappaC_stage2_reg;
    reg [31:0] massResonance_stage2_reg, mirrorResonance_stage2_reg, spectralCoupling_stage2_reg, jScore_stage2_reg;
    
    s3c_three_point_contact contact_inst (
        .handleK(handleK_stage1_reg),
        .handleA(handleA_stage1_reg),
        .handleB(handleB_stage1_reg),
        .kappaA(kappaA_stage2),
        .kappaB(kappaB_stage2),
        .kappaC(kappaC_stage2)
    );
    
    s3c_j_score jscore_inst (
        .handleK(handleK_stage1_reg),
        .handleA(handleA_stage1_reg),
        .handleB(handleB_stage1_reg),
        .massResonance(massResonance_stage2),
        .mirrorResonance(mirrorResonance_stage2),
        .spectralCoupling(spectralCoupling_stage2),
        .total(jScore_stage2)
    );
    
    always @(posedge clk or negedge rst_n) begin
        if (!rst_n) begin
            kappaA_stage2_reg <= 1'b0;
            kappaC_stage2_reg <= 1'b0;
            massResonance_stage2_reg <= 32'd0;
            mirrorResonance_stage2_reg <= 32'd0;
            spectralCoupling_stage2_reg <= 32'd0;
            jScore_stage2_reg <= 32'd0;
        end else begin
            kappaA_stage2_reg <= kappaA_stage2;
            kappaC_stage2_reg <= kappaC_stage2;
            massResonance_stage2_reg <= massResonance_stage2;
            mirrorResonance_stage2_reg <= mirrorResonance_stage2;
            spectralCoupling_stage2_reg <= spectralCoupling_stage2;
            jScore_stage2_reg <= jScore_stage2;
        end
    end
    
    // Pipeline Stage 3: Emission gate
    wire emit_stage3;
    
    s3c_emission_gate emission_inst (
        .kappaA(kappaA_stage2_reg),
        .kappaC(kappaC_stage2_reg),
        .jScore(jScore_stage2_reg),
        .emit(emit_stage3)
    );
    
    // Output registers
    always @(posedge clk or negedge rst_n) begin
        if (!rst_n) begin
            handleK <= 16'd0;
            handleA <= 16'd0;
            handleB <= 16'd0;
            massResonance <= 32'd0;
            mirrorResonance <= 32'd0;
            spectralCoupling <= 32'd0;
            jScore <= 32'd0;
            emit <= 1'b0;
        end else begin
            handleK <= handleK_stage1_reg;
            handleA <= handleA_stage1_reg;
            handleB <= handleB_stage1_reg;
            massResonance <= massResonance_stage2_reg;
            mirrorResonance <= mirrorResonance_stage2_reg;
            spectralCoupling <= spectralCoupling_stage2_reg;
            jScore <= jScore_stage2_reg;
            emit <= emit_stage3;
        end
    end
endmodule

// ═══════════════════════════════════════════════════════════════════════════
// S3C Testbench
// ═══════════════════════════════════════════════════════════════════════════
module s3c_audio_processor_tb;
    reg clk;
    reg rst_n;
    reg [15:0] audio_sample;
    
    wire [15:0] handleK;
    wire [15:0] handleA;
    wire [15:0] handleB;
    wire [31:0] massResonance;
    wire [31:0] mirrorResonance;
    wire [31:0] spectralCoupling;
    wire [31:0] jScore;
    wire emit;
    
    // Instantiate DUT
    s3c_audio_processor dut (
        .clk(clk),
        .rst_n(rst_n),
        .audio_sample(audio_sample),
        .handleK(handleK),
        .handleA(handleA),
        .handleB(handleB),
        .massResonance(massResonance),
        .mirrorResonance(mirrorResonance),
        .spectralCoupling(spectralCoupling),
        .jScore(jScore),
        .emit(emit)
    );
    
    // Clock generation
    initial clk = 0;
    always #18.5185 clk = ~clk;  // 27MHz
    
    // Test stimulus
    initial begin
        // Initialize
        rst_n = 0;
        audio_sample = 16'd0;
        
        #100;
        rst_n = 1;
        
        #100;
        
        // Test samples (matching Python test)
        audio_sample = 16'd100;
        #100;
        $display("Sample 100: k=%d, a=%d, b=%d, mass=%d, emit=%b", 
                 handleK, handleA, handleB, massResonance, emit);
        
        audio_sample = 16'd256;
        #100;
        $display("Sample 256: k=%d, a=%d, b=%d, mass=%d, emit=%b", 
                 handleK, handleA, handleB, massResonance, emit);
        
        audio_sample = 16'd1000;
        #100;
        $display("Sample 1000: k=%d, a=%d, b=%d, mass=%d, emit=%b", 
                 handleK, handleA, handleB, massResonance, emit);
        
        audio_sample = 16'd5000;
        #100;
        $display("Sample 5000: k=%d, a=%d, b=%d, mass=%d, emit=%b", 
                 handleK, handleA, handleB, massResonance, emit);
        
        audio_sample = 16'd10000;
        #100;
        $display("Sample 10000: k=%d, a=%d, b=%d, mass=%d, emit=%b", 
                 handleK, handleA, handleB, massResonance, emit);
        
        #100;
        $finish;
    end
endmodule