#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <string.h>
#include <stdarg.h>
#include <fcntl.h>
#include <jack/jack.h>
#include <jack/midiport.h>
#include <math.h>
#include <time.h>

/* static variables for passthrough test */
static jack_port_t *passthrough_output_port = NULL;
static jack_port_t *passthrough_input_port = NULL;
static float passthrough_phase = 0.0f;
static float passthrough_freq = 440.0f;
static int passthrough_sample_rate = 0;
static long passthrough_total_samples = 0;
static double passthrough_sum_sq = 0.0;
static volatile int passthrough_done = 0;
static volatile int beep_remaining = 0;
static volatile int bursts = 0;
static volatile int prev_above = 0;
static int continuous_sine = 0;

/* variables for MIDI injection (used by send_jack_note_on) */
static volatile int midi_inject_pending = 0;
static jack_port_t *midi_inject_port = NULL;
static jack_client_t *midi_inject_client = NULL;
static unsigned char midi_inject_note = 0;
static unsigned char midi_inject_velocity = 0;

static void safe_usleep(unsigned int usec) {
    struct timespec ts;
    ts.tv_sec = usec / 1000000;
    ts.tv_nsec = (usec % 1000000) * 1000L;
    nanosleep(&ts, NULL);
}

static int midi_inject_process(jack_nframes_t nframes, void *arg) {
    (void)arg;
    if (!midi_inject_port) return 0;
    void *port_buf = jack_port_get_buffer(midi_inject_port, nframes);
    if (!port_buf) return 0;
    jack_midi_clear_buffer(port_buf);
    if (!midi_inject_pending) return 0;
    jack_midi_data_t *buf = jack_midi_event_reserve(port_buf, 0, 3);
    if (!buf) return 0;
    buf[0] = 0x90;
    buf[1] = midi_inject_note;
    buf[2] = midi_inject_velocity;
    midi_inject_pending = 0;
    return 0;
}

/* Helper: initialise the persistent MIDI client (open and connect) */
static int midi_inject_init(const char *target_port) {
    if (midi_inject_client) return 0; /* already initialised */
    jack_status_t st;
    midi_inject_client = jack_client_open("midi_inject_persistent", JackNoStartServer, &st);
    if (!midi_inject_client) return -1;
    midi_inject_port = jack_port_register(midi_inject_client, "out",
                                          JACK_DEFAULT_MIDI_TYPE,
                                          JackPortIsOutput, 0);
    if (!midi_inject_port) return -1;
    jack_set_process_callback(midi_inject_client, midi_inject_process, NULL);
    if (jack_activate(midi_inject_client) != 0) return -1;
    char src[64];
    snprintf(src, sizeof(src), "midi_inject_persistent:out");
    if (jack_connect(midi_inject_client, src, target_port) != 0) return -1;
    return 0;
}

/* Helper: close the persistent MIDI client */
static void midi_inject_close(void) {
    if (midi_inject_client) {
        jack_deactivate(midi_inject_client);
        jack_client_close(midi_inject_client);
        midi_inject_client = NULL;
        midi_inject_port = NULL;
    }
}

/* The test code uses this callback in two ways:
   - For the audio passthrough test (existing function) it still works.
   - For the loop test we need a version that respects the static variables
     beep_remaining and bursts (declared in test_looper_looping).
   We change the existing function to also handle those globals. */
static int passthrough_process(jack_nframes_t nframes, void *arg) {
    (void)arg;
    jack_default_audio_sample_t *out =
        (jack_default_audio_sample_t *)jack_port_get_buffer(passthrough_output_port, nframes);
    const jack_default_audio_sample_t *in =
        (const jack_default_audio_sample_t *)jack_port_get_buffer(passthrough_input_port, nframes);
    if (!out || !in) return 0;
    float *f_out = (float *)out;
    const float *f_in = (const float *)in;
    for (jack_nframes_t i = 0; i < nframes; i++) {
        /* generate beep while beep_remaining > 0 or continuous sine */
        float out_val;
        if (continuous_sine || beep_remaining > 0) {
            out_val = sinf(passthrough_phase);
            passthrough_phase += 2.0f * (float)M_PI * passthrough_freq / passthrough_sample_rate;
            if (passthrough_phase > 2.0f * M_PI)
                passthrough_phase -= 2.0f * M_PI;
            if (beep_remaining > 0) beep_remaining--;
        } else {
            out_val = 0.0f;
        }
        f_out[i] = out_val;

        /* detect bursts on the input (looper output) */
        float sample = f_in[i];
        int above = (fabsf(sample) > 0.05f);
        if (above && !prev_above) {
            bursts++;
        }
        prev_above = above;

        passthrough_sum_sq += (double)f_in[i] * (double)f_in[i];
        passthrough_total_samples++;
    }
    if (passthrough_total_samples >= passthrough_sample_rate * 2) {
        passthrough_done = 1;
    }
    return 0;
}

/*
 * Integration test for the JACK looper.
 *
 * Uses SIGUSR1 to request the looper to report its current state and exit.
 * Verifies that MIDI note‑on and clock messages produce correct state transitions.
 */

#define STATE_IDLE   0
#define STATE_RECORD 1
#define STATE_LOOPING 2
#define STATE_PAUSED 3

#define WAIT_SECONDS 1

/*
 * Start a fresh instance of the looper, wait for JACK ports to appear,
 * return its PID, or -1 on failure.
 */
static pid_t start_looper(void) {
    pid_t pid = fork();
    if (pid < 0) {
        perror("fork");
        return -1;
    }
    if (pid == 0) {
        /* child: suppress stderr messages */
        close(2);
        open("/dev/null", O_WRONLY);
        execl("./looper", "looper", NULL);
        perror("execl");
        _exit(1);
    }
    printf("Started looper (pid %d)\n", (int)pid);
    sleep(3);  /* wait for JACK ports to register */
    return pid;
}


static int test_audio_pass_through(void) {
    printf("Test: audio pass‑through (connectivity)\n");
    pid_t pid = start_looper();
    if (pid < 0) return 1;
    /* ensure fresh MIDI connection for this test */
    midi_inject_close();
    jack_client_t *client;
    jack_status_t status;
    client = jack_client_open("test_passthrough", JackNoStartServer, &status);
    if (client == NULL) {
        fprintf(stderr, "  SKIP: cannot open JACK client (server not running?)\n");
        kill(pid, SIGTERM);
        waitpid(pid, NULL, 0);
        return 1;
    }
    jack_port_t *output_port = jack_port_register(client, "output",
                           JACK_DEFAULT_AUDIO_TYPE,
                           JackPortIsOutput, 0);
    jack_port_t *input_port = jack_port_register(client, "input",
                           JACK_DEFAULT_AUDIO_TYPE,
                           JackPortIsInput, 0);
    if (!output_port || !input_port) {
        fprintf(stderr, "  FAIL: could not register ports\n");
        jack_client_close(client);
        kill(pid, SIGTERM);
        waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(200000);
    const char *looper_input = "looper:input";
    const char *looper_output = "looper:output";
    char my_output[64], my_input[64];
    snprintf(my_output, sizeof(my_output), "test_passthrough:output");
    snprintf(my_input, sizeof(my_input), "test_passthrough:input");
    if (jack_connect(client, my_output, looper_input) != 0) {
        fprintf(stderr, "  FAIL: cannot connect test_passthrough:output -> looper:input\n");
        jack_client_close(client);
        kill(pid, SIGTERM);
        waitpid(pid, NULL, 0);
        return 1;
    }
    if (jack_connect(client, looper_output, my_input) != 0) {
        fprintf(stderr, "  FAIL: cannot connect looper:output -> test_passthrough:input\n");
        jack_client_close(client);
        kill(pid, SIGTERM);
        waitpid(pid, NULL, 0);
        return 1;
    }
    passthrough_output_port = output_port;
    passthrough_input_port = input_port;
    passthrough_phase = 0.0f;
    passthrough_freq = 440.0f;
    passthrough_sample_rate = jack_get_sample_rate(client);
    passthrough_total_samples = 0;
    passthrough_sum_sq = 0.0;
    passthrough_done = 0;
    continuous_sine = 1;          /* enable continuous tone for this test */
    beep_remaining = 0;           /* not needed */
    jack_set_process_callback(client, passthrough_process, NULL);
    if (jack_activate(client) != 0) {
        fprintf(stderr, "  FAIL: cannot activate client\n");
        jack_client_close(client);
        kill(pid, SIGTERM);
        waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(2200000);
    int saw_input = passthrough_done;
    double rms = passthrough_total_samples > 0 ?
                 sqrt(passthrough_sum_sq / passthrough_total_samples) : 0.0;
    jack_deactivate(client);
    jack_client_close(client);
    kill(pid, SIGTERM);
    waitpid(pid, NULL, 0);
    if (!saw_input) {
        fprintf(stderr, "  FAIL: looper did not produce output (no callback run?)\n");
        return 1;
    }
    if (rms < 0.001) {
        fprintf(stderr, "  FAIL: looper output RMS too small (%.6f)\n", rms);
        return 1;
    }
    printf("  PASS (RMS %.6f)\n", rms);
    return 0;
}


/* Helper: open a transient JACK client, send a MIDI note‑on, close */
static jack_client_t *midi_persistent_client = NULL;
static jack_port_t *midi_persistent_port = NULL;

static int send_jack_note_on(const char *target_port, unsigned char note, unsigned char velocity) {
    /* initialise client on first call (per‑test) */
    if (midi_inject_init(target_port) != 0) return -1;

    midi_inject_note = note;
    midi_inject_velocity = velocity;
    midi_inject_pending = 1;

    /* wait for delivery (process callback clears the flag) */
    for (int attempts = 0; attempts < 100; attempts++) {
        safe_usleep(10000);
        if (!midi_inject_pending) break;
    }
    return 0;
}

/* must be called after all tests */
static void close_persistent_midi(void) {
    if (midi_persistent_client) {
        jack_deactivate(midi_persistent_client);
        jack_client_close(midi_persistent_client);
        midi_persistent_client = NULL;
        midi_persistent_port = NULL;
    }
}

/*
 * Full loop recording test:
 *  1. start looper
 *  2. open JACK test client (audio)
 *  3. send note‑on to move IDLE->RECORD
 *  4. generate a short 440 Hz beep (~0.1 s) while recording
 *  5. send note‑on to move RECORD->LOOPING
 *  6. monitor looper output for the beep being repeated (≥3 times)
 */
static int test_looper_looping(void) {
    printf("Test: loop recording and playback (expect ≥3 repetitions)\n");

    pid_t pid = start_looper();
    if (pid < 0) return 1;

    /* ensure fresh MIDI connection for this test */
    midi_inject_close();

    jack_client_t *client;
    jack_status_t status;
    client = jack_client_open("test_looping", JackNoStartServer, &status);
    if (!client) {
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  SKIP: JACK not running?\n");
        return 1;
    }
    jack_port_t *audio_out = jack_port_register(client, "out",
                           JACK_DEFAULT_AUDIO_TYPE,
                           JackPortIsOutput, 0);
    jack_port_t *audio_in = jack_port_register(client, "in",
                           JACK_DEFAULT_AUDIO_TYPE,
                           JackPortIsInput, 0);
    if (!audio_out || !audio_in) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(200000);               /* wait for ports to appear */
    /* connect test:out -> looper:input, looper:output -> test:in */
    char my_out[64], my_in[64];
    snprintf(my_out, sizeof(my_out), "test_looping:out");
    snprintf(my_in,  sizeof(my_in),  "test_looping:in");
    if (jack_connect(client, my_out, "looper:input") ||
        jack_connect(client, "looper:output", my_in)) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }

    /* first note‑on: IDLE -> RECORD */
    if (send_jack_note_on("looper:control", 1, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(500000);               /* allow state to change (500ms) */

    int sr = jack_get_sample_rate(client);
    continuous_sine = 0;          /* disable continuous tone */
    beep_remaining = (int)(0.1f * sr);   /* 0.1 second beep */
    bursts = 0;
    prev_above = 0;

    passthrough_output_port = audio_out;
    passthrough_input_port = audio_in;
    passthrough_phase = 0.0f;
    passthrough_freq = 440.0f;
    passthrough_sample_rate = sr;
    passthrough_total_samples = 0;
    passthrough_sum_sq = 0.0;
    passthrough_done = 0;

    jack_set_process_callback(client, passthrough_process, NULL);
    if (jack_activate(client)) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }

    safe_usleep(150000);               /* let beep start */

    /* ensure beep is fully captured */
    safe_usleep(800000);   /* 0.8s after start of beep */

    if (send_jack_note_on("looper:control", 1, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }

    /* wait enough time for several loops (4 seconds to be safe) */
    safe_usleep(4000000);

    jack_deactivate(client);
    jack_client_close(client);

    kill(pid, SIGTERM);
    waitpid(pid, NULL, 0);

    int got_bursts = bursts;
    printf("  detected bursts: %d\n", got_bursts);
    if (got_bursts < 3) {
        fprintf(stderr, "  FAIL: expected ≥3 bursts, got %d\n", got_bursts);
        return 1;
    }
    printf("  PASS (at least 3 repetitions)\n");
    return 0;
}

/* test multiple channels */
static int test_multiple_channels(void) {
    printf("Test: dynamic channel creation via MIDI command\n");
    pid_t pid = start_looper();
    if (pid < 0) return 1;

    /* ensure fresh MIDI connection for this test */
    midi_inject_close();

    jack_client_t *client;
    jack_status_t status;
    client = jack_client_open("test_multi", JackNoStartServer, &status);
    if (!client) {
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  SKIP: no JACK\n");
        return 1;
    }

    if (send_jack_note_on("looper:control", 60, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send note 60 failed\n");
        return 1;
    }
    /* wait long enough for the looper's main loop to process the add command
       (it sleeps for 1 second between checks, so 1.5 s is safe) */
    safe_usleep(1500000);

    int found = 0;
    const char **ports = jack_get_ports(client, NULL, JACK_DEFAULT_AUDIO_TYPE, 0);
    if (ports) {
        for (int i = 0; ports[i]; i++) {
            if (strstr(ports[i], "looper:channel1_input")) {
                found = 1;
                break;
            }
        }
        jack_free(ports);
    }
    jack_client_close(client);
    kill(pid, SIGTERM);
    waitpid(pid, NULL, 0);

    if (!found) {
        fprintf(stderr, "  FAIL: channel1_input port not created after add command\n");
        return 1;
    }
    printf("  PASS (channel created)\n");
    return 0;
}

/* test control‑key modifier (note 64 + note 62) */
static int test_control_key_modifier(void) {
    printf("Test: control‑key modifier triggers state transition via note 62\n");
    pid_t pid = start_looper();
    if (pid < 0) return 1;
    /* ensure fresh MIDI connection for this test */
    midi_inject_close();
    jack_client_t *client;
    jack_status_t status;
    client = jack_client_open("test_ctrl_key", JackNoStartServer, &status);
    if (!client) {
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  SKIP: no JACK\n");
        return 1;
    }
    /* connect same as in test_looper_looping but no beep generation */
    jack_port_t *audio_out = jack_port_register(client, "out",
                           JACK_DEFAULT_AUDIO_TYPE,
                           JackPortIsOutput, 0);
    jack_port_t *audio_in = jack_port_register(client, "in",
                           JACK_DEFAULT_AUDIO_TYPE,
                           JackPortIsInput, 0);
    if (!audio_out || !audio_in) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(200000);
    char my_out[64], my_in[64];
    snprintf(my_out, sizeof(my_out), "test_ctrl_key:out");
    snprintf(my_in,  sizeof(my_in),  "test_ctrl_key:in");
    if (jack_connect(client, my_out, "looper:input") ||
        jack_connect(client, "looper:output", my_in)) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    /* First send note 64 (control key) */
    if (send_jack_note_on("looper:control", 64, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send note 64 failed\n");
        return 1;
    }
    safe_usleep(200000);
    /* Now send note 62 (toggle channel 0) */
    if (send_jack_note_on("looper:control", 62, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send note 62 failed\n");
        return 1;
    }
    /* Wait for looper to enter RECORD and detect audio */
    int sr = jack_get_sample_rate(client);
    continuous_sine = 0;
    beep_remaining = (int)(0.1f * sr);   /* 0.1 second beep */
    bursts = 0;
    prev_above = 0;
    passthrough_output_port = audio_out;
    passthrough_input_port = audio_in;
    passthrough_phase = 0.0f;
    passthrough_freq = 440.0f;
    passthrough_sample_rate = sr;
    passthrough_total_samples = 0;
    passthrough_sum_sq = 0.0;
    passthrough_done = 0;
    jack_set_process_callback(client, passthrough_process, NULL);
    if (jack_activate(client)) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(200000);   /* allow beep */
    /* send note 62 again under control key to move RECORD->LOOPING */
    if (send_jack_note_on("looper:control", 64, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: control key re‑send\n");
        return 1;
    }
    safe_usleep(200000);
    if (send_jack_note_on("looper:control", 62, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send note 62 for loop\n");
        return 1;
    }
    safe_usleep(2000000);
    jack_deactivate(client);
    jack_client_close(client);
    kill(pid, SIGTERM);
    waitpid(pid, NULL, 0);
    int got_bursts = bursts;
    printf("  detected bursts: %d\n", got_bursts);
    if (got_bursts < 3) {
        fprintf(stderr, "  FAIL: expected ≥3 bursts, got %d\n", got_bursts);
        return 1;
    }
    printf("  PASS (control‑key modifier works)\n");
    return 0;
}

/* test bind channel */
static int test_bind_channel(void) {
    printf("Test: control‑key bind channel (note 0) and toggle\n");
    pid_t pid = start_looper();
    if (pid < 0) return 1;
    /* ensure fresh MIDI connection for this test */
    midi_inject_close();
    jack_client_t *client;
    jack_status_t status;
    client = jack_client_open("test_bind", JackNoStartServer, &status);
    if (!client) {
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  SKIP: no JACK\n");
        return 1;
    }
    jack_port_t *audio_out = jack_port_register(client, "out",
                           JACK_DEFAULT_AUDIO_TYPE,
                           JackPortIsOutput, 0);
    jack_port_t *audio_in = jack_port_register(client, "in",
                           JACK_DEFAULT_AUDIO_TYPE,
                           JackPortIsInput, 0);
    if (!audio_out || !audio_in) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(200000);
    char my_out[64], my_in[64];
    snprintf(my_out, sizeof(my_out), "test_bind:out");
    snprintf(my_in,  sizeof(my_in),  "test_bind:in");
    if (jack_connect(client, my_out, "looper:input") ||
        jack_connect(client, "looper:output", my_in)) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    /* Send control key + note 0 to bind to channel 0 */
    if (send_jack_note_on("looper:control", 64, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send control key failed\n");
        return 1;
    }
    safe_usleep(200000);
    if (send_jack_note_on("looper:control", 0, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send bind note 0 failed\n");
        return 1;
    }
    safe_usleep(200000);
    /* Now toggle using control+note62 – should toggle channel 0 */
    if (send_jack_note_on("looper:control", 64, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send control key again failed\n");
        return 1;
    }
    safe_usleep(200000);
    if (send_jack_note_on("looper:control", 62, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send toggle note 62 failed\n");
        return 1;
    }
    /* Wait and detect bursts as before */
    int sr = jack_get_sample_rate(client);
    continuous_sine = 0;
    beep_remaining = (int)(0.1f * sr);
    bursts = 0;
    prev_above = 0;
    passthrough_output_port = audio_out;
    passthrough_input_port = audio_in;
    passthrough_phase = 0.0f;
    passthrough_freq = 440.0f;
    passthrough_sample_rate = sr;
    passthrough_total_samples = 0;
    passthrough_sum_sq = 0.0;
    passthrough_done = 0;
    jack_set_process_callback(client, passthrough_process, NULL);
    if (jack_activate(client)) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(200000); /* allow beep */
    /* send control+note62 again to move RECORD->LOOPING */
    if (send_jack_note_on("looper:control", 64, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: control key for loop\n");
        return 1;
    }
    safe_usleep(200000);
    if (send_jack_note_on("looper:control", 62, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: toggle for loop\n");
        return 1;
    }
    safe_usleep(2000000);
    jack_deactivate(client);
    jack_client_close(client);
    kill(pid, SIGTERM);
    waitpid(pid, NULL, 0);
    int got_bursts = bursts;
    printf("  detected bursts: %d\n", got_bursts);
    if (got_bursts < 3) {
        fprintf(stderr, "  FAIL: expected >=3 bursts, got %d\n", got_bursts);
        return 1;
    }
    printf("  PASS (bind and toggle)\n");
    return 0;
}

/* test unbind */
static int test_bind_unbind(void) {
    printf("Test: bind to channel 5, unbind, then toggle default (channel 0)\n");
    pid_t pid = start_looper();
    if (pid < 0) return 1;
    /* ensure fresh MIDI connection for this test */
    midi_inject_close();
    jack_client_t *client;
    jack_status_t status;
    client = jack_client_open("test_unbind", JackNoStartServer, &status);
    if (!client) {
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  SKIP: no JACK\n");
        return 1;
    }
    jack_port_t *audio_out = jack_port_register(client, "out",
                           JACK_DEFAULT_AUDIO_TYPE,
                           JackPortIsOutput, 0);
    jack_port_t *audio_in = jack_port_register(client, "in",
                           JACK_DEFAULT_AUDIO_TYPE,
                           JackPortIsInput, 0);
    if (!audio_out || !audio_in) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(200000);
    char my_out[64], my_in[64];
    snprintf(my_out, sizeof(my_out), "test_unbind:out");
    snprintf(my_in,  sizeof(my_in),  "test_unbind:in");
    if (jack_connect(client, my_out, "looper:input") ||
        jack_connect(client, "looper:output", my_in)) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    /* Bind to channel 5 */
    if (send_jack_note_on("looper:control", 64, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send control key failed\n");
        return 1;
    }
    safe_usleep(200000);
    if (send_jack_note_on("looper:control", 5, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: bind to 5 failed\n");
        return 1;
    }
    safe_usleep(200000);
    /* Unbind (reset to 0) */
    if (send_jack_note_on("looper:control", 64, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: control key for unbind\n");
        return 1;
    }
    safe_usleep(200000);
    if (send_jack_note_on("looper:control", 63, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send unbind note 63 failed\n");
        return 1;
    }
    safe_usleep(200000);
    /* Now toggle with control+62 – should affect channel 0 */
    if (send_jack_note_on("looper:control", 64, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: control key for toggle\n");
        return 1;
    }
    safe_usleep(200000);
    if (send_jack_note_on("looper:control", 62, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: toggle note 62\n");
        return 1;
    }
    /* Wait for beep and loop */
    int sr = jack_get_sample_rate(client);
    continuous_sine = 0;
    beep_remaining = (int)(0.1f * sr);
    bursts = 0;
    prev_above = 0;
    passthrough_output_port = audio_out;
    passthrough_input_port = audio_in;
    passthrough_phase = 0.0f;
    passthrough_freq = 440.0f;
    passthrough_sample_rate = sr;
    passthrough_total_samples = 0;
    passthrough_sum_sq = 0.0;
    passthrough_done = 0;
    jack_set_process_callback(client, passthrough_process, NULL);
    if (jack_activate(client)) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(200000); /* allow beep */
    /* second control+62 -> loop */
    if (send_jack_note_on("looper:control", 64, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: control key for loop\n");
        return 1;
    }
    safe_usleep(200000);
    if (send_jack_note_on("looper:control", 62, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: toggle for loop\n");
        return 1;
    }
    safe_usleep(2000000);
    jack_deactivate(client);
    jack_client_close(client);
    kill(pid, SIGTERM);
    waitpid(pid, NULL, 0);
    int got_bursts = bursts;
    printf("  detected bursts: %d\n", got_bursts);
    if (got_bursts < 3) {
        fprintf(stderr, "  FAIL: expected >=3 bursts, got %d\n", got_bursts);
        return 1;
    }
    printf("  PASS (unbind works, toggle channel 0)\n");
    return 0;
}

/* test remove channel */
static int test_remove_channel(void) {
    printf("Test: dynamic channel removal via MIDI command\n");
    pid_t pid = start_looper();
    if (pid < 0) return 1;
    /* ensure fresh MIDI connection for this test */
    midi_inject_close();
    jack_client_t *client;
    jack_status_t status;
    client = jack_client_open("test_remove", JackNoStartServer, &status);
    if (!client) {
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  SKIP: no JACK\n");
        return 1;
    }
    /* add channel */
    if (send_jack_note_on("looper:control", 60, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send note 60 failed\n");
        return 1;
    }
    safe_usleep(1500000);
    /* verify channel1_input exists */
    const char **ports = jack_get_ports(client, NULL, JACK_DEFAULT_AUDIO_TYPE, 0);
    int found = 0;
    if (ports) {
        for (int i = 0; ports[i]; i++) {
            if (strstr(ports[i], "looper:channel1_input")) {
                found = 1;
                break;
            }
        }
        jack_free(ports);
    }
    if (!found) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: channel1_input not created\n");
        return 1;
    }
    printf("  channel1_input created\n");
    /* remove channel */
    if (send_jack_note_on("looper:control", 61, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: send note 61 failed\n");
        return 1;
    }
    safe_usleep(3000000);
    /* verify channel1_input has disappeared */
    ports = jack_get_ports(client, NULL, JACK_DEFAULT_AUDIO_TYPE, 0);
    int still_found = 0;
    if (ports) {
        for (int i = 0; ports[i]; i++) {
            if (strstr(ports[i], "looper:channel1_input")) {
                still_found = 1;
                break;
            }
        }
        jack_free(ports);
    }
    jack_client_close(client);
    kill(pid, SIGTERM);
    waitpid(pid, NULL, 0);
    if (still_found) {
        fprintf(stderr, "  FAIL: channel1_input not removed after remove command\n");
        return 1;
    }
    printf("  PASS (channel removed)\n");
    return 0;
}

/* ------------------------------------------------------------
 * Helper: generate a simple 440 Hz WAV file for load tests
 * ------------------------------------------------------------ */
static int generate_test_wav(const char *path, unsigned sample_rate, unsigned duration_frames) {
    int fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
    if (fd < 0) return -1;
    unsigned data_bytes = duration_frames * 2;
    unsigned file_size = 44 + data_bytes;
    unsigned char header[44];
    memset(header, 0, 44);
    memcpy(header, "RIFF", 4);
    unsigned chunk_size = file_size - 8;
    header[4] = chunk_size & 0xff; header[5] = (chunk_size>>8)&0xff;
    header[6] = (chunk_size>>16)&0xff; header[7] = (chunk_size>>24)&0xff;
    memcpy(header+8, "WAVE", 4);
    memcpy(header+12, "fmt ", 4);
    header[16]=16; header[17]=0; header[18]=0; header[19]=0;
    header[20]=1; header[21]=0;   /* PCM */
    header[22]=1; header[23]=0;   /* mono */
    header[24]= sample_rate & 0xff; header[25]=(sample_rate>>8)&0xff;
    header[26]=(sample_rate>>16)&0xff; header[27]=(sample_rate>>24)&0xff;
    unsigned br = sample_rate * 2;
    header[28]= br & 0xff; header[29]=(br>>8)&0xff;
    header[30]=(br>>16)&0xff; header[31]=(br>>24)&0xff;
    header[32]=2; header[33]=0;
    header[34]=16; header[35]=0;
    memcpy(header+36, "data", 4);
    header[40]= data_bytes & 0xff; header[41]=(data_bytes>>8)&0xff;
    header[42]=(data_bytes>>16)&0xff; header[43]=(data_bytes>>24)&0xff;
    if (write(fd, header, 44) != 44) { close(fd); return -1; }
    for (unsigned i = 0; i < duration_frames; i++) {
        float sample = sinf(2.0f * (float)M_PI * 440.0f * i / sample_rate);
        int16_t s = (int16_t)(sample * 32767);
        if (write(fd, &s, 2) != 2) { close(fd); return -1; }
    }
    close(fd);
    return 0;
}

/* ------------------------------------------------------------
 * Test: load WAV file (note 70 under control key)
 * ------------------------------------------------------------ */
static int test_wav_load(void) {
    printf("Test: load WAV file into channel 0 and detect playback\n");
    if (generate_test_wav("loop.wav", 48000, 48000) != 0) {
        fprintf(stderr, "  FAIL: could not create test WAV\n");
        return 1;
    }
    pid_t pid = start_looper();
    if (pid < 0) { unlink("loop.wav"); return 1; }
    /* ensure fresh MIDI connection for this test */
    midi_inject_close();
    jack_client_t *client;
    jack_status_t status;
    client = jack_client_open("test_wav_load", JackNoStartServer, &status);
    if (!client) {
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        unlink("loop.wav");
        fprintf(stderr, "  SKIP: no JACK\n");
        return 1;
    }
    jack_port_t *audio_out = jack_port_register(client, "out", JACK_DEFAULT_AUDIO_TYPE, JackPortIsOutput, 0);
    jack_port_t *audio_in = jack_port_register(client, "in", JACK_DEFAULT_AUDIO_TYPE, JackPortIsInput, 0);
    if (!audio_out || !audio_in) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        unlink("loop.wav");
        return 1;
    }
    safe_usleep(200000);
    if (jack_connect(client, "test_wav_load:out", "looper:input") ||
        jack_connect(client, "looper:output", "test_wav_load:in")) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        unlink("loop.wav");
        return 1;
    }
    /* set up passthrough callback before sending load command */
    int sr = jack_get_sample_rate(client);
    continuous_sine = 0;
    beep_remaining = 0;
    bursts = 0;
    prev_above = 0;
    passthrough_output_port = audio_out;
    passthrough_input_port = audio_in;
    passthrough_phase = 0.0f;
    passthrough_freq = 440.0f;
    passthrough_sample_rate = sr;
    passthrough_total_samples = 0;
    passthrough_sum_sq = 0.0;
    passthrough_done = 0;
    jack_set_process_callback(client, passthrough_process, NULL);
    if (jack_activate(client)) {
        jack_deactivate(client);
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        unlink("loop.wav");
        return 1;
    }
    /* send control key + note 70 to trigger load */
    if (send_jack_note_on("looper:control", 64, 127) != 0) {
        jack_deactivate(client);
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        unlink("loop.wav"); return 1;
    }
    safe_usleep(1000000);  /* 1 second to ensure control key is processed */
    if (send_jack_note_on("looper:control", 70, 127) != 0) {
        jack_deactivate(client);
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        unlink("loop.wav"); return 1;
    }
    /* wait for the loop to be fully loaded and playing */
    safe_usleep(3000000);
    /* continue listening for the rest of the time */
    safe_usleep(6000000); /* total 9 seconds after activation */
    jack_deactivate(client);
    jack_client_close(client);
    kill(pid, SIGTERM); waitpid(pid, NULL, 0);
    unlink("loop.wav");
    int got_bursts = bursts;
    double rms = passthrough_total_samples > 0 ?
                 sqrt(passthrough_sum_sq / passthrough_total_samples) : 0.0;
    printf("  detected bursts: %d, RMS: %.6f\n", got_bursts, rms);
    if (got_bursts < 3) {
        fprintf(stderr, "  FAIL: expected ≥3 bursts from loaded loop, got %d, RMS=%.6f\n", got_bursts, rms);
        return 1;
    }
    printf("  PASS (loaded loop plays)\n");
    return 0;
}

/* ------------------------------------------------------------
 * Test: save WAV file (note 71 under control key)
 * ------------------------------------------------------------ */
static int test_wav_save(void) {
    printf("Test: save WAV file from loop\n");
    pid_t pid = start_looper();
    if (pid < 0) return 1;
    /* ensure fresh MIDI connection for this test */
    midi_inject_close();
    jack_client_t *client;
    jack_status_t status;
    client = jack_client_open("test_wav_save", JackNoStartServer, &status);
    if (!client) {
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  SKIP: no JACK\n");
        return 1;
    }
    jack_port_t *audio_out = jack_port_register(client, "out", JACK_DEFAULT_AUDIO_TYPE, JackPortIsOutput, 0);
    jack_port_t *audio_in = jack_port_register(client, "in", JACK_DEFAULT_AUDIO_TYPE, JackPortIsInput, 0);
    if (!audio_out || !audio_in) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(200000);
    if (jack_connect(client, "test_wav_save:out", "looper:input") ||
        jack_connect(client, "looper:output", "test_wav_save:in")) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    /* record a beep: send note 1 (toggle channel 0) */
    if (send_jack_note_on("looper:control", 1, 127) != 0) {
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(200000);
    /* start generating a beep */
    int sr = jack_get_sample_rate(client);
    continuous_sine = 0;
    beep_remaining = (int)(0.5f * sr);
    bursts = 0; prev_above = 0;
    passthrough_output_port = audio_out;
    passthrough_input_port = audio_in;
    passthrough_phase = 0.0f;
    passthrough_freq = 440.0f;
    passthrough_sample_rate = sr;
    passthrough_total_samples = 0;
    passthrough_sum_sq = 0.0;
    passthrough_done = 0;
    jack_set_process_callback(client, passthrough_process, NULL);
    if (jack_activate(client)) {
        jack_deactivate(client);
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(800000);
    /* toggle again to stop recording and start looping */
    if (send_jack_note_on("looper:control", 1, 127) != 0) {
        jack_deactivate(client);
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(500000);
    /* send control key + note 71 to save */
    if (send_jack_note_on("looper:control", 64, 127) != 0) {
        jack_deactivate(client);
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(200000);
    if (send_jack_note_on("looper:control", 71, 127) != 0) {
        jack_deactivate(client);
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        return 1;
    }
    safe_usleep(2000000);
    /* check save.wav exists and has data */
    int fd = open("save.wav", O_RDONLY);
    if (fd < 0) {
        jack_deactivate(client);
        jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: save.wav not created\n");
        return 1;
    }
    unsigned char hdr[44];
    if (read(fd, hdr, 44) != 44) {
        close(fd); unlink("save.wav");
        jack_deactivate(client); jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: short header\n");
        return 1;
    }
    unsigned data_bytes = hdr[40] | (hdr[41]<<8) | (hdr[42]<<16) | (hdr[43]<<24);
    close(fd);
    if (data_bytes == 0) {
        unlink("save.wav");
        jack_deactivate(client); jack_client_close(client);
        kill(pid, SIGTERM); waitpid(pid, NULL, 0);
        fprintf(stderr, "  FAIL: empty save.wav\n");
        return 1;
    }
    printf("  save.wav data size: %u bytes\n", data_bytes);
    unlink("save.wav");
    jack_deactivate(client);
    jack_client_close(client);
    kill(pid, SIGTERM); waitpid(pid, NULL, 0);
    printf("  PASS (save.wav created)\n");
    return 0;
}

int main(void) {
    /* 1. binary must exist */
    if (system("test -x ./looper") != 0) {
        fprintf(stderr, "FATAL: looper binary not found\n");
        return 1;
    }

    /* 2. MIDI transition tests (skipped – no external tools) */

    /* 3. Audio pass‑through test – must work for basic connectivity */
    test_audio_pass_through();

    int failures = 0;

    /* 4. Test that looping feature is now implemented */
    if (test_looper_looping() != 0) {
        fprintf(stderr, "  FAILED\n");
        failures++;
    }

    /* 5. Test multiple dynamic channels */
    if (test_multiple_channels() != 0) {
        fprintf(stderr, "  FAILED\n");
        failures++;
    }

    /* 6. Test control‑key modifier */
    if (test_control_key_modifier() != 0) {
        fprintf(stderr, "  FAILED\n");
        failures++;
    }

    /* 7. Test bind channel */
    if (test_bind_channel() != 0) {
        fprintf(stderr, "  FAILED\n");
        failures++;
    }

    /* 8. Test unbind */
    if (test_bind_unbind() != 0) {
        fprintf(stderr, "  FAILED\n");
        failures++;
    }

    /* 9. Test channel removal */
    if (test_remove_channel() != 0) {
        fprintf(stderr, "  FAILED\n");
        failures++;
    }

    /* 10. Test WAV load */
    if (test_wav_load() != 0) {
        fprintf(stderr, "  FAILED\n");
        failures++;
    }

    /* 11. Test WAV save */
    if (test_wav_save() != 0) {
        fprintf(stderr, "  FAILED\n");
        failures++;
    }

    close_persistent_midi();

    if (failures > 0) {
        fprintf(stderr, "%d test(s) FAILED\n", failures);
        return 1;
    }
    printf("All tests completed successfully.\n");
    return 0;
}