// Adaptive Fabric Connector - Top Level
// Target: Gowin GW1NR-9 (Tang Nano 9K)
// Ties together Metaprobe sensing, CMYK routing, and GCL/Hachimoji transport

`timescale 1ns / 1ps

module adaptive_fabric_connector (
    input  wire        clk,        // 27MHz from Tang Nano
    input  wire        rst_n,
    
    // USB-UART Bridge (FTDI)
    input  wire        uart_rx,
    output wire        uart_tx,
    
    // Physical Layer Probing
    input  wire        usb_c_mode, // High if Type-C manifold detected
    input  wire        usb4_mode,  // High if USB4 (40Gbps) manifold active
    
    // Status LEDs
    output wire [5:0]  leds        // Visual feedback of CMYK state
);

    // ═══════════════════════════════════════════════════════════════════════════
    // Metaprobe Stress Sensing
    // ═══════════════════════════════════════════════════════════════════════════
    wire [31:0] raw_stress;
    metaprobe_stress_sensor probe_inst (
        .clk(clk),
        .rst_n(rst_n),
        .stress(raw_stress)
    );
    
    // Physical state verification: we lower the effective stress based on link quality.
    // Standard Type-C (10Gbps+) reduces stress by 50%.
    // USB4 (40Gbps+) reduces stress by 75% to indicate ultra-stable settlement.
    assign fabric_stress = usb4_mode  ? (raw_stress >> 2) : 
                          usb_c_mode ? (raw_stress >> 1) : 
                          raw_stress;

    // ═══════════════════════════════════════════════════════════════════════════
    // Topological Residual Tracking
    // ═══════════════════════════════════════════════════════════════════════════
    wire [31:0] topo_residual;
    wire        topo_pulse;
    
    topological_residual_engine topo_inst (
        .clk(clk),
        .rst_n(rst_n),
        .stress_a(usb_c_mode ? 32'h00010000 : 32'h0),
        .stress_b(usb4_mode  ? 32'h00020000 : 32'h0),
        .stress_combined(fabric_stress),
        .residual(topo_residual),
        .pulse(topo_pulse)
    );

    // ═══════════════════════════════════════════════════════════════════════════
    // CMYK Adaptive Routing
    // ═══════════════════════════════════════════════════════════════════════════
    wire [1:0] routing_state;
    wire [31:0] encoder_residual;
    wire       fabric_gate;
    
    cmyk_adaptive_router router_inst (
        .clk(clk),
        .rst_n(rst_n),
        .v_t(32'h00010000),      // Input signal (1.0)
        .m_t(fabric_stress),     // Metaprobe stress from RO array
        .delta_t(topo_residual), // Apply topological residual as stress delta
        .state(routing_state),
        .residual(encoder_residual),
        .gate_open(fabric_gate)
    );

    // ═══════════════════════════════════════════════════════════════════════════
    // Data Transport (UART Passthrough with Gating)
    // ═══════════════════════════════════════════════════════════════════════════
    // In a full implementation, this would handle Hachimoji codon decoding.
    // Here, we gate the UART stream based on the fabric state.
    
    assign uart_tx = fabric_gate ? uart_rx : 1'b1; // Simple echo or gate

    // ═══════════════════════════════════════════════════════════════════════════
    // LED Feedback
    // ═══════════════════════════════════════════════════════════════════════════
    // LED 0-1: CMYK State
    // LED 2: Gate status
    // LED 3-5: Stress level (coarse)
    
    assign leds[1:0] = ~routing_state; // Active low LEDs on Tang Nano
    assign leds[2]   = ~topo_pulse;    // Pulse LED on topological interaction
    assign leds[3]   = ~(fabric_stress > 32'h2000);
    assign leds[4]   = ~(fabric_stress > 32'h6000);
    assign leds[5]   = ~(fabric_stress > 32'hA000);

endmodule