#include "common.h"
#include "miniaudio.h"
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <unistd.h>

#define KEY_LENGTH 256
#define MAX_SOUNDS_PER_KEY 32

struct msg_target {
  FILE *file_handle;
  int sock_fd;
  struct sockaddr *sock_addr;
  ssize_t sock_addr_size;
};

struct ipc_data {
  struct sockaddr_un sa_server, sa_client;
  int sock_fd;
};

struct audio_data {
  ma_engine engine;
};

struct sfx_pool {
  struct sfx_pool_item {
    char key[KEY_LENGTH];
    ma_sound sounds[MAX_SOUNDS_PER_KEY];
    int last_index;

    float volume;
    float pitch_min, pitch_max;
  } *sounds;
  int cap, use;
};

ssize_t send_data(struct msg_target tgt, const void *data, size_t len);
ssize_t send_txt(struct msg_target tgt, const char *fmt, ...);
void execute_command(struct msg_target tgt, const char *command, const char *params);

bool ipc_init(const char *sock_path);
void ipc_loop();

bool audio_init();

void sfx_pool_clear(void);
void sfx_pool_grow(int size);
struct sfx_pool_item *sfx_pool_lookup(const char *key);
struct sfx_pool_item *sfx_pool_find_place_for(const char *key);
struct sfx_pool_item *sfx_pool_load(const char *key, const char *path);

struct ipc_data ipc = { 0 };
struct audio_data audio = { 0 };
struct sfx_pool sounds_pool = { 0, 0, 0 };

int main(int argc, char **argv) {
  sfx_pool_grow(32);
  printf("audio_init()\n");
  if (!audio_init()) {
    return EXIT_FAILURE;
  }

  char *sock_path = DAEMON_SOCKET_PATH;
  if (!ipc_init(sock_path)) {
    unlink(sock_path);
    return EXIT_FAILURE;
  }

  ipc_loop();
  unlink(sock_path);
}

bool ipc_init(const char *sock_path) {
  SOFT_EXPECT(ipc.sock_fd = socket(AF_UNIX, SOCK_DGRAM, 0), > 0, false);

  memset(&ipc.sa_server, 0, sizeof(ipc.sa_server));
  memset(&ipc.sa_client, 0, sizeof(ipc.sa_client));
  ipc.sa_server.sun_family = AF_UNIX;
  strncpy(ipc.sa_server.sun_path, sock_path, sizeof(ipc.sa_server.sun_path) - 1);
  unlink(ipc.sa_server.sun_path);
  SOFT_EXPECT(bind(ipc.sock_fd, (struct sockaddr *)&ipc.sa_server, sizeof(struct sockaddr_un)), >= 0, false);
  return true;
}

void ipc_loop() {
  static char buffer[BUFFER_SIZE];
  ssize_t data_len;
  socklen_t sl_client = sizeof(ipc.sa_client);
  while ((data_len = recvfrom(ipc.sock_fd, buffer, sizeof(buffer) - 1, 0, (struct sockaddr *)&ipc.sa_client, &sl_client)) != -1) {
    buffer[data_len] = '\0';
    struct sockaddr_un *sau_client = &ipc.sa_client;
    char *command = buffer;
    char *params = strchr(command, ' ');
    if (params != NULL) {
      *params = '\0';
      params++;
    }
    execute_command((struct msg_target) { 0, ipc.sock_fd, (struct sockaddr *)&ipc.sa_client, sl_client }, command, params);
    SOFT_EXPECT(sendto(ipc.sock_fd, "OK\n", 4, 0, (struct sockaddr *)&ipc.sa_client, sl_client), == 4,);
    SOFT_EXPECT(sendto(ipc.sock_fd, "", 0, 0, (struct sockaddr *)&ipc.sa_client, sl_client), == 0,);
    sl_client = sizeof(ipc.sa_client);
  }
}

bool audio_init() {
    ma_result result;
    SOFT_EXPECT((result = ma_engine_init(NULL, &audio.engine)), == MA_SUCCESS, false);
    return true;
}

ssize_t send_data(struct msg_target tgt, const void *data, size_t len) {
  ssize_t written;
  if (tgt.file_handle) {
    if ((written = fwrite(data, 1, len, tgt.file_handle)) != len) {
      SOFT_PANIC_FMT("fwrite(ptr=%p, size=%zd, nmemb=%zd, stream=%p) -> %zd",
          data, 1, len, tgt.file_handle, written);
    }
  } else {
    if ((written = sendto(tgt.sock_fd, data, len, 0, tgt.sock_addr, tgt.sock_addr_size)) != len) {
      SOFT_PANIC_FMT("sendto(socket=%d, message=%p, length=%zd, flags=%d, dest_addr=%p, dest_len=%zd) -> %zd",
          tgt.sock_fd, data, len, 0, tgt.sock_addr, tgt.sock_addr_size, written);
    }
  }

  return written;
}

ssize_t send_txt(struct msg_target tgt, const char *fmt, ...) {
  static char txtbuf[BUFFER_SIZE];
  va_list args;
  va_start(args, fmt);
  vsnprintf(txtbuf, BUFFER_SIZE - 1, fmt, args);
  va_end(args);
  return send_data(tgt, txtbuf, strlen(txtbuf) + 1);
}

void execute_command(struct msg_target tgt, const char *command, const char *params) {
  send_txt(tgt, "Received '%s' with '%s'\n", command, params);

  if (0 == strcmp(command, "load")) {
    const char *key = params;
    char *path = strchr(params, ' ');
    *path = '\0';
    path++;
    struct sfx_pool_item *sound = sfx_pool_load(key, path);
    if (sound == NULL) {
      send_txt(tgt, "Load failed\n");
    } else {
      send_txt(tgt, "Loaded as %08x\n", adler32(key, strlen(key)));
    }
  } else if (0 == strcmp(command, "play")) {
    struct sfx_pool_item *sound = sfx_pool_lookup(params);
    if (!sound) {
      send_txt(tgt, "No such sound: '%s'\n", params);
      return;
    }

    ma_sound *sfx = &sound->sounds[(sound->last_index++) % MAX_SOUNDS_PER_KEY];
    ma_sound_set_pitch(sfx, sound->pitch_min);
    ma_sound_set_volume(sfx, sound->volume);
    ma_sound_start(sfx);
  }
}


void sfx_pool_clear() {
  for (int i = 0; i < sounds_pool.cap; i++) {
    if (sounds_pool.sounds[i].key[0]) {
      for (int j = 0; j < MAX_SOUNDS_PER_KEY; j++) {
        ma_sound_uninit(&sounds_pool.sounds[i].sounds[j]);
      }
    }
  }
}

void sfx_pool_grow(int size) {
  if (size <= sounds_pool.cap) return;

  // TODO: move to realloc?
  struct sfx_pool_item *new_items = calloc(size, sizeof(struct sfx_pool_item));
  EXPECT(new_items == NULL, == false);

  int used = 0;
  for (int i = 0; i < sounds_pool.cap; i++) {
    if (sounds_pool.sounds[i].key[0] == '\0') continue;
    uint32_t new_hash = adler32(sounds_pool.sounds[i].key, strlen(sounds_pool.sounds[i].key));
    for (int offset = 0; offset < size; offset++) {
      int index = (new_hash + offset) % size;
      if (new_items[index].key[0] == '\0') {
        memcpy(&new_items[index], &sounds_pool.sounds[i], sizeof(struct sfx_pool_item));
        used++;
        break;
      }
    }
  }

  free(sounds_pool.sounds);
  sounds_pool.use = used;
  sounds_pool.cap = size;
  sounds_pool.sounds = new_items;
}

struct sfx_pool_item *sfx_pool_lookup(const char *key) {
  if (key == NULL) return NULL;
  uint32_t hash = adler32(key, strlen(key));
  for (int offset = 0; offset < sounds_pool.cap; offset++) {
    int index = (hash + offset) % sounds_pool.cap;
    if (0 == strncmp(key, sounds_pool.sounds[index].key, KEY_LENGTH)) {
      return &sounds_pool.sounds[index];
    }
  }
  return NULL;
}

struct sfx_pool_item *sfx_pool_find_place_for(const char *key) {
  uint32_t hash = adler32(key, strlen(key));
  for (int offset = 0; offset < sounds_pool.cap; offset++) {
    int index = (hash + offset) % sounds_pool.cap;
    if (sounds_pool.sounds[index].key[0] == '\0' || 0 == strncmp(sounds_pool.sounds[index].key, key, KEY_LENGTH)) {
      return &sounds_pool.sounds[index];
    }
  }
  return NULL;
}

struct sfx_pool_item *sfx_pool_load(const char *key, const char *path) {
  if (key == NULL || path == NULL) return NULL;

  if (sounds_pool.use / (float)sounds_pool.cap >= 0.75) {
    sfx_pool_grow(sounds_pool.cap + 32);
  }

  struct sfx_pool_item *sound = sfx_pool_find_place_for(key);
  SOFT_EXPECT(sound == NULL, == false, NULL);

  ma_result res;
  SOFT_EXPECT(res = ma_sound_init_from_file(&audio.engine, path, 0, 0, 0, &sound->sounds[0]), == MA_SUCCESS, NULL);

  bool keep_parameters = false;
  if ((keep_parameters = (0 == strncmp(sound->key, key, KEY_LENGTH)))) {
    for (int i = 0; i < MAX_SOUNDS_PER_KEY; i++) {
      ma_sound_uninit(&sound->sounds[i]);
    }
  }

  for (int i = 1; i < MAX_SOUNDS_PER_KEY; i++) {
    SOFT_EXPECT(res = ma_sound_init_copy(&audio.engine, &sound->sounds[0], 0, 0, &sound->sounds[i]), == MA_SUCCESS, NULL);
  }

  if (!keep_parameters) {
    sound->last_index = 0;
    sound->pitch_max = 1.0;
    sound->pitch_min = 1.0;
    sound->volume = 1.0;
  }

  strncpy(sound->key, key, KEY_LENGTH);

  return sound;
}