/*
 * Warlock's Stave — Quick FFI Demo Harness
 *
 * Compile:  gcc -o demo demo.c -ldl -Wl,-rpath,./target/release
 * Run:      LD_LIBRARY_PATH=./target/release ./demo
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dlfcn.h>

/* Mirrors the 4 C-FFI functions from libstave_core.so */
typedef void*  (*init_fn)(void);
typedef const char* (*ingest_fn)(void*, const unsigned char*, size_t, unsigned long, unsigned int);
typedef void   (*free_str_fn)(const char*);
typedef void   (*destroy_fn)(void*);

int main(void) {
    printf("=== Warlock's Stave FFI Demo ===\n\n");

    /* --- Load the shared library --- */
    void *lib = dlopen("./target/release/libstave_core.so", RTLD_NOW);
    if (!lib) {
        fprintf(stderr, "dlopen failed: %s\n", dlerror());
        fprintf(stderr, "Run ./build.sh first, then use:\n");
        fprintf(stderr, "  LD_LIBRARY_PATH=./target/release ./demo\n");
        return 1;
    }

    init_fn     init   = (init_fn)    dlsym(lib, "initialize_warlock_stave");
    ingest_fn   ingest = (ingest_fn)  dlsym(lib, "stave_ingest_frame");
    free_str_fn freestr = (free_str_fn)dlsym(lib, "free_stave_string");
    destroy_fn  destroy = (destroy_fn) dlsym(lib, "destroy_warlock_stave");

    if (!init || !ingest || !freestr || !destroy) {
        fprintf(stderr, "dlsym failed: %s\n", dlerror());
        dlclose(lib);
        return 1;
    }

    /* --- Initialize the engine --- */
    void *ctx = init();
    printf("[Engine] Context created: %p\n\n", ctx);

    /*
     * Feed a realistic x86-64 sequence.
     * Each frame: (bytes, length, RIP, EFLAGS)
     *
     * Instructions:
     *   0x7FF0:  48 31 C0          xor rax, rax
     *   0x7FF3:  48 89 C3          mov rbx, rax
     *   0x7FF6:  0F 84 10 00 00 00 je +0x10  (conditional — ZF=1 in EFLAGS)
     *   0x7FFC:  E9 05 00 00 00    jmp +0x5   (unconditional)
     *   0x8001:  48 83 C4 28       add rsp, 0x28
     */
    struct { unsigned char *bytes; size_t len; unsigned long rip; unsigned int eflags; } frames[] = {
        { (unsigned char[]){ 0x48, 0x31, 0xC0 },                    3, 0x7FF0, 0x202 },  /* ZF=1 */
        { (unsigned char[]){ 0x48, 0x89, 0xC3 },                    3, 0x7FF3, 0x202 },
        { (unsigned char[]){ 0x0F, 0x84, 0x10, 0x00, 0x00, 0x00 }, 6, 0x7FF6, 0x246 },  /* ZF=1, SF=1 */
        { (unsigned char[]){ 0xE9, 0x05, 0x00, 0x00, 0x00 },       5, 0x7FFC, 0x246 },
        { (unsigned char[]){ 0x48, 0x83, 0xC4, 0x28 },             4, 0x8001, 0x246 },
    };
    int n = sizeof(frames) / sizeof(frames[0]);

    for (int i = 0; i < n; i++) {
        const char *json = ingest(ctx, frames[i].bytes, frames[i].len,
                                  frames[i].rip, frames[i].eflags);
        printf("[Frame %d] RIP=0x%04lX  bytes=%zu  EFLAGS=0x%X\n",
               i+1, frames[i].rip, frames[i].len, frames[i].eflags);
        printf("  %s\n\n", json);
        freestr(json);
    }

    /* --- Telemetry round-trip: hit the same cell twice --- */
    printf("[Frame 6] Re-visiting RIP=0x7FF0 (heatmap intensity should increase)...\n");
    const char *json = ingest(ctx,
        (unsigned char[]){ 0x48, 0x31, 0xC0 }, 3, 0x7FF0, 0x202);
    printf("  %s\n\n", json);
    freestr(json);

    /* --- Conditional branch with ZF=0 (not-taken path) --- */
    printf("[Frame 7] je with ZF=0 (should report ConditionNotMet)...\n");
    json = ingest(ctx,
        (unsigned char[]){ 0x0F, 0x84, 0x10, 0x00, 0x00, 0x00 }, 6, 0x7FF6, 0x242);
    printf("  %s\n\n", json);
    freestr(json);

    /* --- Dictionary scan: URL pattern in bytes --- */
    printf("[Frame 8] Bytes containing 'http://' (dictionary hit expected)...\n");
    json = ingest(ctx,
        (unsigned char[]){ 0x68, 0x74, 0x74, 0x70, 0x3A, 0x2F, 0x2F }, 7, 0x9000, 0x246);
    printf("  %s\n\n", json);
    freestr(json);

    /* --- Cleanup --- */
    destroy(ctx);
    dlclose(lib);

    printf("=== Done. ===\n");
    return 0;
}