#define _DEFAULT_SOURCE
#include "audio_compressor.h"
#include "debug_config.h"
#include "mem.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <time.h>

static int tests_run = 0, tests_passed = 0;

#define TEST(expr, msg) do { \
    tests_run++; \
    if (expr) { tests_passed++; } \
    else { fprintf(stderr, "FAIL: %s (%s:%d)\n", msg, __FILE__, __LINE__); } \
} while(0)

/* ── helpers ── */

static void fill_sine(int16_t* buf, size_t n, int freq, int sample_rate) {
    for (size_t i = 0; i < n; i++)
        buf[i] = (int16_t)(14000.0f * sinf(2.0f * (float)M_PI * (float)freq * (float)i / (float)sample_rate));
}

static void fill_silence(int16_t* buf, size_t n) {
    memset(buf, 0, n * sizeof(int16_t));
}

/* ── tests ── */

static void test_create_destroy(void) {
    struct audio_compressor* ac = audio_compressor_create();
    TEST(ac != NULL, "create");
    audio_compressor_configure(ac, &(audio_compressor_config_t){0});
    audio_compressor_reset(ac);
    audio_compressor_destroy(ac);
    /* check no leaks via u_get_allocated_count */
    size_t unfreed = u_get_allocated_count();
    TEST(unfreed == 0, "no leaks after destroy");
    if (unfreed > 0) {
        fprintf(stderr, "  unfreed blocks: %zu\n", unfreed);
        u_report_unfreed_blocks();
    }
}

static void test_disabled_passthrough(void) {
    struct audio_compressor* ac = audio_compressor_create();
    audio_compressor_configure(ac, &(audio_compressor_config_t){0});
    audio_compressor_set_enabled(ac, 0);

    int16_t in[960]; fill_sine(in, 960, 440, 48000);
    audio_compressor_push(ac, in, 960);

    const int16_t* out = audio_compressor_output(ac);
    size_t sz = audio_compressor_output_size(ac);
    TEST(sz == 960, "passthrough size");
    int match = 1;
    for (size_t i = 0; i < sz; i++) { if (out[i] != in[i]) { match = 0; break; } }
    TEST(match, "passthrough data unchanged");

    audio_compressor_destroy(ac);
}

static void test_basic_push_flush(void) {
    struct audio_compressor* ac = audio_compressor_create();
    audio_compressor_config_t cfg = {0};
    cfg.sample_rate = 48000; cfg.channels = 1;
    cfg.block_duration_ms = 20; cfg.lookback_ms = 200; cfg.lookahead_ms = 100;
    cfg.max_gain_db = 30.0f; cfg.rise_rate_per_500ms = 2.0f; cfg.target_level = 0.25f;
    audio_compressor_configure(ac, &cfg);

    int16_t in[960];
    /* push 20 blocks (400ms) — enough to fill lookback+lookahead and flush */
    for (int b = 0; b < 20; b++) {
        fill_sine(in, 960, 440, 48000);
        audio_compressor_push(ac, in, 960);
    }
    audio_compressor_flush(ac);

    const int16_t* out = audio_compressor_output(ac);
    size_t sz = audio_compressor_output_size(ac);
    TEST(sz > 0, "output not empty");
    TEST(sz >= 960 * 10, "output has reasonable size");

    /* check not all silence */
    float sum_sq = 0.0f;
    for (size_t i = 0; i < sz; i++) { float v = (float)out[i] / 32768.0f; sum_sq += v * v; }
    float rms = sqrtf(sum_sq / (float)sz);
    TEST(rms > 0.001f, "output not silence");

    audio_compressor_destroy(ac);
}

static void test_silence_in_silence_out(void) {
    struct audio_compressor* ac = audio_compressor_create();
    audio_compressor_config_t cfg = {0};
    cfg.sample_rate = 48000; cfg.channels = 1;
    cfg.block_duration_ms = 20; cfg.lookback_ms = 200; cfg.lookahead_ms = 100;
    cfg.max_gain_db = 30.0f; cfg.rise_rate_per_500ms = 2.0f; cfg.target_level = 0.25f;
    audio_compressor_configure(ac, &cfg);

    int16_t in[960]; fill_silence(in, 960);
    for (int b = 0; b < 20; b++)
        audio_compressor_push(ac, in, 960);
    audio_compressor_flush(ac);

    const int16_t* out = audio_compressor_output(ac);
    size_t sz = audio_compressor_output_size(ac);
    TEST(sz > 0, "output not empty (silence)");
    /* silence should still be silence (envelope ≈ 0.0001, gain limited) */
    float sum_sq = 0.0f;
    for (size_t i = 0; i < sz; i++) { float v = (float)out[i] / 32768.0f; sum_sq += v * v; }
    float rms = sqrtf(sum_sq / (float)sz);
    TEST(rms < 0.01f, "silence stays near zero");
    audio_compressor_destroy(ac);
}

static void test_reset(void) {
    struct audio_compressor* ac = audio_compressor_create();
    audio_compressor_config_t cfg = {0};
    cfg.sample_rate = 48000; cfg.channels = 1;
    cfg.block_duration_ms = 20; cfg.lookback_ms = 200; cfg.lookahead_ms = 100;
    cfg.max_gain_db = 30.0f; cfg.rise_rate_per_500ms = 2.0f; cfg.target_level = 0.25f;
    audio_compressor_configure(ac, &cfg);

    int16_t in[960];
    fill_sine(in, 960, 440, 48000);
    for (int b = 0; b < 15; b++) audio_compressor_push(ac, in, 960);
    audio_compressor_flush(ac);

    audio_compressor_reset(ac);

    fill_sine(in, 960, 880, 48000);
    for (int b = 0; b < 15; b++) audio_compressor_push(ac, in, 960);
    audio_compressor_flush(ac);

    const int16_t* out = audio_compressor_output(ac);
    size_t sz = audio_compressor_output_size(ac);
    TEST(sz > 960 * 10, "output after reset has data");

    float sum_sq = 0.0f;
    for (size_t i = 0; i < sz; i++) { float v = (float)out[i] / 32768.0f; sum_sq += v * v; }
    float rms = sqrtf(sum_sq / (float)sz);
    TEST(rms > 0.001f, "output after reset not silence");

    audio_compressor_destroy(ac);
}

static void test_stress(void) {
    srand((unsigned)time(NULL));
    for (int cycle = 0; cycle < 200; cycle++) {
        struct audio_compressor* ac = audio_compressor_create();
        audio_compressor_config_t cfg = {0};
        cfg.sample_rate = 48000; cfg.channels = 1;
        cfg.block_duration_ms = 20; cfg.lookback_ms = (rand() % 200) + 50;
        cfg.lookahead_ms = (rand() % 100) + 20;
        cfg.max_gain_db = (float)(rand() % 31);
        cfg.rise_rate_per_500ms = 1.1f + (float)(rand() % 90) / 10.0f;
        cfg.target_level = 0.1f + (float)(rand() % 30) / 100.0f;
        audio_compressor_configure(ac, &cfg);

        int16_t in[960];
        int blocks = (rand() % 30) + 5;
        for (int b = 0; b < blocks; b++) {
            for (int i = 0; i < 960; i++)
                in[i] = (int16_t)((rand() % 28000) - 14000);
            audio_compressor_push(ac, in, 960);
        }
        audio_compressor_flush(ac);

        audio_compressor_reset(ac);
        blocks = (rand() % 10) + 1;
        for (int b = 0; b < blocks; b++) {
            for (int i = 0; i < 960; i++)
                in[i] = (int16_t)((rand() % 2000) - 1000);
            audio_compressor_push(ac, in, 960);
        }
        audio_compressor_flush(ac);

        const int16_t* out = audio_compressor_output(ac);
        size_t sz = audio_compressor_output_size(ac);
        TEST(sz > 0, "stress output not empty");

        audio_compressor_destroy(ac);

        size_t unfreed = u_get_allocated_count();
        TEST(unfreed == 0, "stress no leaks");
        if (unfreed > 0) break;
    }
}

int main(void) {
    debug_set_level(DEBUG_LEVEL_NONE);

    test_create_destroy();
    test_disabled_passthrough();
    test_basic_push_flush();
    test_silence_in_silence_out();
    test_reset();
    test_stress();

    fprintf(stderr, "\n%d/%d tests passed\n", tests_passed, tests_run);
    return tests_passed == tests_run ? 0 : 1;
}