// ============================================================================
// ACE Learning Layer: Runtime parameter setters
// ============================================================================

void hkm_ace_set_drain_threshold(int class_idx, uint32_t threshold) {
    // Validate inputs
    if (class_idx < 0 || class_idx >= TINY_NUM_CLASSES) {
        return;
    }
    if (threshold < 16 || threshold > 2048) {
        return;
    }

    // Set per-class threshold (used by remote free drain logic)
    g_remote_drain_thresh_per_class[class_idx] = (int)threshold;
}
#include "tiny_fc_api.h"
int tiny_fc_room(int class_idx) {
    if (class_idx < 0 || class_idx >= TINY_NUM_CLASSES) return 0;
    TinyFastCache* fc = &g_fast_cache[class_idx];
    // Effective per-class cap comes from g_fast_cap (env-tunable),
    // clamped by the static storage capacity TINY_FASTCACHE_CAP.
    uint16_t eff_cap = g_fast_cap[class_idx];
    if (eff_cap > TINY_FASTCACHE_CAP) eff_cap = TINY_FASTCACHE_CAP;
    int room = (int)eff_cap - fc->top;
    return room > 0 ? room : 0;
}

int tiny_fc_push_bulk(int class_idx, void** arr, int n) {
    if (!arr || n <= 0) return 0;
    if (class_idx < 0 || class_idx >= TINY_NUM_CLASSES) return 0;
    TinyFastCache* fc = &g_fast_cache[class_idx];
    uint16_t eff_cap = g_fast_cap[class_idx];
    if (eff_cap > TINY_FASTCACHE_CAP) eff_cap = TINY_FASTCACHE_CAP;
    int room = (int)eff_cap - fc->top;
    if (room <= 0) return 0;
    int take = n < room ? n : room;
    // Forward fill with light unrolling to reduce branch overhead
    int i = 0;
    for (; i + 3 < take; i += 4) {
        fc->items[fc->top++] = arr[i];
        fc->items[fc->top++] = arr[i + 1];
        fc->items[fc->top++] = arr[i + 2];
        fc->items[fc->top++] = arr[i + 3];
    }
    for (; i < take; i++) {
        fc->items[fc->top++] = arr[i];
    }
    return take;
}

// ========= Tiny Guard (targeted debug; low overhead when disabled) =========
static int g_tiny_guard_enabled = -1;
static int g_tiny_guard_class = 2;
static int g_tiny_guard_limit = 8;
static __thread int g_tiny_guard_seen = 0;

static inline int tiny_guard_enabled_runtime(void) {
    if (__builtin_expect(g_tiny_guard_enabled == -1, 0)) {
        // Enabled via HAKMEM_DEBUG_LEVEL >= 4 (DEBUG level)
        // Legacy: HAKMEM_TINY_GUARD=1 still works for compatibility
        g_tiny_guard_enabled = hak_debug_check_level("HAKMEM_TINY_GUARD", 4);

        // Special-purpose parameters (kept for targeted debugging)
        const char* ec = getenv("HAKMEM_TINY_GUARD_CLASS");
        if (ec && *ec) g_tiny_guard_class = atoi(ec);
        const char* el = getenv("HAKMEM_TINY_GUARD_MAX");
        if (el && *el) g_tiny_guard_limit = atoi(el);
        if (g_tiny_guard_limit <= 0) g_tiny_guard_limit = 8;
    }
    return g_tiny_guard_enabled;
}

int tiny_guard_is_enabled(void) { return tiny_guard_enabled_runtime(); }

static void tiny_guard_dump_bytes(const char* tag, const uint8_t* p, size_t n) {
    fprintf(stderr, "[TGUARD] %s:", tag);
    for (size_t i = 0; i < n; i++) fprintf(stderr, " %02x", p[i]);
    fprintf(stderr, "\n");
}

void tiny_guard_on_alloc(int cls, void* base, void* user, size_t stride) {
    if (!tiny_guard_enabled_runtime() || cls != g_tiny_guard_class) return;
    if (g_tiny_guard_seen++ >= g_tiny_guard_limit) return;
    uint8_t* b = (uint8_t*)base;
    uint8_t* u = (uint8_t*)user;
    fprintf(stderr, "[TGUARD] alloc cls=%d base=%p user=%p stride=%zu hdr=%02x\n",
            cls, base, user, stride, b[0]);
    // 隣接ヘッダ可視化（前後）
    tiny_guard_dump_bytes("around_base", b, (stride >= 8 ? 8 : stride));
    tiny_guard_dump_bytes("next_header", b + stride, 4);
}

void tiny_guard_on_invalid(void* user_ptr, uint8_t hdr) {
    if (!tiny_guard_enabled_runtime()) return;
    if (g_tiny_guard_seen++ >= g_tiny_guard_limit) return;
    uint8_t* u = (uint8_t*)user_ptr;
    fprintf(stderr, "[TGUARD] invalid header at user=%p hdr=%02x prev=%02x next=%02x\n",
            user_ptr, hdr, *(u - 2), *(u));
    tiny_guard_dump_bytes("dump_before", u - 8, 8);
    tiny_guard_dump_bytes("dump_after", u, 8);
}