/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
 * vfetch - neofetch but the ascii part is a video
 *
 * Copyright (C) 2026  Doan Luu Duc Tai
 *
 */

#include "utils.h"
#include <sys/types.h>
#include <errno.h>
#include <ftw.h>
#include <miniaudio.h>
#include <pthread.h>
#include <stdarg.h>
#include <stdatomic.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <termios.h>
#include <time.h>
#include <unistd.h>
#include "config.h"
#include "state.h"

void log_debug(bool debug_flag, const char *format, ...) {
  if (!debug_flag) {
    return;
  }

  va_list args;
  (void)fputs("[DEBUG] ", stderr);
  va_start(args, format);
  (void)vfprintf(stderr, format, args);
  va_end(args);
  (void)fputc('\n', stderr);
  (void)fflush(stderr);
}

void log_verbose(AppState *state,
                 bool verbose_flag,
                 bool debug_flag,
                 const char *format,
                 ...) {
  if (!verbose_flag && !debug_flag) {
    return;
  }

  FILE *const stream = (int)debug_flag ? stderr : stdout;
  if (stream == stdout) {
    (void)pthread_mutex_lock(&state->stdout_mutex);
  }

  va_list args;
  (void)fputs("[VERBOSE] ", stream);
  va_start(args, format);
  (void)vfprintf(stream, format, args);
  va_end(args);
  (void)fputc('\n', stream);
  (void)fflush(stream);

  if (stream == stdout) {
    (void)pthread_mutex_unlock(&state->stdout_mutex);
  }
}

#define K_ERROR_BUFFER_SIZE 256
void log_vfetch_error(VfetchError err, const char *context_msg) {
  const char *err_str = NULL;

  switch (err) {
    case VFETCH_SUCCESS:
    case VFETCH_SUCCESS_EXIT_EARLY:
      return;
    case VFETCH_ERROR_MEMORY_ALLOCATION:
      err_str = "Memory allocation failed";
      break;
    case VFETCH_ERROR_INVALID_ARGUMENT:
      err_str = "Invalid argument provided";
      break;
    case VFETCH_ERROR_FILE_IO:
      err_str = "File I/O error";
      break;
    case VFETCH_ERROR_PIPE_CREATION:
      err_str = "Pipe creation failed";
      break;
    case VFETCH_ERROR_FORK_FAILED:
      err_str = "Fork failed";
      break;
    case VFETCH_ERROR_EXEC_FAILED:
      err_str = "Exec failed";
      break;
    case VFETCH_ERROR_WAITPID_FAILED:
      err_str = "Waitpid failed";
      break;
    case VFETCH_ERROR_COMMAND_FAILED:
      err_str = "Command failed";
      break;
    case VFETCH_ERROR_MKDIR_FAILED:
      err_str = "Failed to create directory";
      break;
    case VFETCH_ERROR_STAT_FAILED:
      err_str = "Failed to stat file";
      break;
    case VFETCH_ERROR_PATH_FAILED:
      err_str = "Failed to resolve path";
      break;
    case VFETCH_ERROR_THREAD_CREATION:
      err_str = "Thread creation failed";
      break;
    case VFETCH_ERROR_MUTEX_INIT:
      err_str = "Mutex initialization failed";
      break;
    case VFETCH_ERROR_MMAP_FAILED:
      err_str = "Mmap failed";
      break;
    case VFETCH_ERROR_VIDEO_OPEN_FAILED:
      err_str = "Could not open video file (MPEG-1 required)";
      break;
    case VFETCH_ERROR_AV_STREAM_INFO:
      err_str = "Could not read video stream info";
      break;
    case VFETCH_ERROR_MA_INIT:
      err_str = "Miniaudio initialization failed";
      break;
    case VFETCH_ERROR_CACHE_INVALID:
      err_str = "Cache is invalid or corrupt";
      break;
    case VFETCH_ERROR_CHAFA_CONFIG:
      err_str = "Chafa configuration failed";
      break;
    default:
      err_str = "Unknown Error";
      break;
  }

  if (context_msg && context_msg[0] != '\0') {
    (void)fprintf(stderr, "ERROR: %s: %s\n", err_str, context_msg);
  } else {
    (void)fprintf(stderr, "ERROR: %s\n", err_str);
  }

  bool is_sys_err =
      (err == VFETCH_ERROR_FILE_IO || err == VFETCH_ERROR_STAT_FAILED ||
       err == VFETCH_ERROR_MKDIR_FAILED || err == VFETCH_ERROR_FORK_FAILED ||
       err == VFETCH_ERROR_MMAP_FAILED) != 0;

  if (is_sys_err && errno != 0) {
    char err_buf[K_ERROR_BUFFER_SIZE] = {0};
    if (strerror_r(errno, err_buf, sizeof(err_buf)) == 0) {
      (void)fprintf(stderr, "       System error: %s\n", err_buf);
    }
  }

  errno = 0;
}
#undef K_ERROR_BUFFER_SIZE

_Noreturn void die(VfetchError err, const char *context_msg) {
  log_vfetch_error(err, context_msg);
  restore_terminal();
  exit(map_vfetch_error_to_exit_code(err));
}

void print_progress(AppState *state, size_t current, size_t total) {
  if (total == 0) {
    return;
  }

  char *status_line =
      g_strdup_printf("\rCaching: %zu / %zu \x1b[K", current, total);

  if (status_line != NULL) {
    (void)pthread_mutex_lock(&state->stdout_mutex);
    (void)fputs(status_line, stdout);
    (void)fflush(stdout);
    (void)pthread_mutex_unlock(&state->stdout_mutex);

    g_free(status_line);
  }
}

#define K_PROGRESS_UPDATE_INTERVAL_NS 100000000L
void *progress_display_thread_func(void *arg) {
  struct timespec req = {0};

  ProgressThreadArgs *progress_args = (ProgressThreadArgs *)arg;
  AppState *state = progress_args->state;
  size_t total_frames = progress_args->total_frames;
  size_t completed_count = 0;

  while (completed_count < total_frames) {
    if (atomic_load_explicit(&state->exit_requested, memory_order_acquire) ||
        atomic_load_explicit(&state->processing_finished,
                             memory_order_acquire)) {
      break;
    }

    completed_count = atomic_load_explicit(&state->ascii_frames_completed,
                                           memory_order_relaxed);
    print_progress(state, completed_count, total_frames);

    req.tv_sec = 0;
    req.tv_nsec = K_PROGRESS_UPDATE_INTERVAL_NS;
    (void)nanosleep(&req, NULL);
  }

  if (!atomic_load_explicit(&state->exit_requested, memory_order_acquire)) {
    print_progress(state, total_frames, total_frames);
  }

  (void)pthread_mutex_lock(&state->stdout_mutex);
  (void)fputc('\n', stdout);
  (void)fflush(stdout);
  (void)pthread_mutex_unlock(&state->stdout_mutex);

  free(progress_args);
  return NULL;
}
#undef K_PROGRESS_UPDATE_INTERVAL_NS

void restore_terminal(void) {
  static bool has_been_restored = false;

  if (has_been_restored || !global_signal_handler_state_ptr) {
    return;
  }
  has_been_restored = true;

  AppState *state = global_signal_handler_state_ptr;
  VfetchArgs *args = state->args;

  (void)pthread_mutex_lock(&state->stdout_mutex);

  (void)fputs("\x1b[0m\x1b[?25h", stdout);

  if (atomic_load_explicit(&state->animation_has_started,
                           memory_order_acquire)) {
    size_t anim_h = (size_t)args->height;
    size_t fetch_h =
        atomic_load_explicit(&state->last_fetch_lines, memory_order_relaxed);

    size_t content_height = (anim_h > fetch_h) ? anim_h : fetch_h;
    size_t final_row = (size_t)args->pad_y + content_height + 1;

    (void)fprintf(stdout, "\x1b[%zu;1H\n", final_row);
  }

  if (atomic_load_explicit(&state->termios_saved, memory_order_acquire)) {
    (void)tcsetattr(STDIN_FILENO, TCSANOW, &state->original_termios);
  }

  (void)fflush(stdout);
  (void)pthread_mutex_unlock(&state->stdout_mutex);
}

void setup_terminal(AppState *state) {
  if (isatty(STDIN_FILENO)) {
    if (tcgetattr(STDIN_FILENO, &state->original_termios) == 0) {
      struct termios raw_termios = {0};

      atomic_store_explicit(&state->termios_saved, true, memory_order_release);

      raw_termios = state->original_termios;
      raw_termios.c_lflag &= (tcflag_t) ~(ECHO | ICANON);
      (void)tcsetattr(STDIN_FILENO, TCSANOW, &raw_termios);
    }
  }
}

void set_cursor_visible(AppState *state, bool visible) {
  atomic_store_explicit(&state->cursor_visible, visible, memory_order_release);
  bool is_visible =
      atomic_load_explicit(&state->cursor_visible, memory_order_acquire);
  if (is_visible) {
    const char *cmd = "\x1b[?25h";
    if (write(STDOUT_FILENO, cmd, strlen(cmd)) < 0) {
      perror("write failed when showing cursor");
    }
  } else {
    const char *cmd = "\x1b[?25l";
    if (write(STDOUT_FILENO, cmd, strlen(cmd)) < 0) {
      perror("write failed when hiding cursor");
    }
  }
}

#define K_ANSI_ESCAPE_BUFFER_PADDING 32
void append_block_to_buffer(char *buffer,
                            size_t buffer_size,
                            size_t *current_len,
                            uint32_t start_x,
                            uint32_t start_y,
                            const char *text_block,
                            size_t text_block_len) {
  const char *block_end = text_block + text_block_len;
  const char *line_start = text_block;
  int line_offset_y = 0;

  while (line_start < block_end) {
    const char *line_end = (const char *)memchr(
        line_start, '\n', (size_t)(block_end - line_start));
    if (line_end == NULL) {
      line_end = block_end;
    }

    size_t line_len = (size_t)(line_end - line_start);

    if (line_len > 0 && line_start[line_len - 1] == '\r') {
      line_len--;
    }

    if (line_len > 0) {
      if (*current_len + line_len + K_ANSI_ESCAPE_BUFFER_PADDING <
          buffer_size) {
        int written = snprintf(buffer + *current_len,
                               buffer_size - *current_len,
                               "\x1b[%u;%uH%.*s",
                               start_y + (uint32_t)line_offset_y,
                               start_x + 1,
                               (int)line_len,
                               line_start);
        if (written > 0) {
          *current_len += (size_t)written;
        }
      }
    }

    line_offset_y++;
    line_start = line_end + 1;
  }
}
#undef K_ANSI_ESCAPE_BUFFER_PADDING

#define K_ANSI_ESCAPE_BUFFER_PADDING 32
void clear_rect_in_buffer(char *buffer,
                          size_t buffer_size,
                          size_t *current_len,
                          const Rect *rect) {
  if (rect->height == 0 || rect->width == 0) {
    return;
  }

  char *clear_line = malloc(rect->width + 1);

  if (!clear_line) {
    (void)fputs("ERROR: Memory allocation failed in clear_rect_in_buffer\n",
                stderr);
    return;
  }

  (void)memset(clear_line, ' ', rect->width);
  clear_line[rect->width] = '\0';

  for (size_t idx = 0; idx < rect->height; idx++) {
    if (*current_len + rect->width + K_ANSI_ESCAPE_BUFFER_PADDING <
        buffer_size) {
      int written = snprintf(buffer + *current_len,
                             buffer_size - *current_len,
                             "\x1b[%u;%uH%s",
                             rect->start_y + (uint32_t)idx,
                             rect->start_x + 1,
                             clear_line);
      if (written > 0) {
        *current_len += (size_t)written;
      }
    }
  }

  free(clear_line);
}
#undef K_ANSI_ESCAPE_BUFFER_PADDING

VfetchError
run_command_fork_output(const gchar *command, gchar **output, bool debug_flag) {
  gchar *stdout_buf = NULL;
  gchar *stderr_buf = NULL;
  gint wait_status = 0;
  GError *gerr = NULL;

  log_debug(debug_flag, "Executing: %s", command);

  if (!g_spawn_command_line_sync(
          command, &stdout_buf, &stderr_buf, &wait_status, &gerr)) {
    log_debug(debug_flag, "GLib spawn failed: %s", gerr->message);
    g_error_free(gerr);
    return VFETCH_ERROR_EXEC_FAILED;
  }

  if (WIFEXITED(wait_status) && WEXITSTATUS(wait_status) != 0) {
    log_debug(
        debug_flag, "Command exited with status %d", WEXITSTATUS(wait_status));
    if (stderr_buf && *stderr_buf) {
      log_debug(debug_flag, "Command Stderr: %s", stderr_buf);
    }
    g_free(stdout_buf);
    g_free(stderr_buf);
    return VFETCH_ERROR_COMMAND_FAILED;
  }

  if (output) {
    if (stderr_buf && *stderr_buf) {
      *output = g_strconcat(stdout_buf, stderr_buf, NULL);
      g_free(stdout_buf);
    } else {
      *output = stdout_buf;
    }
  } else {
    g_free(stdout_buf);
  }

  g_free(stderr_buf);
  return VFETCH_SUCCESS;
}

int unlink_cb(const char *fpath,
              const struct stat *stat_buf,
              int typeflag,
              struct FTW *ftwbuf) {
  (void)stat_buf;
  (void)ftwbuf;
  int result = 0;

  if (typeflag == FTW_DP || typeflag == FTW_D) {
    result = rmdir(fpath);
  } else {
    result = unlink(fpath);
  }

  if (result != 0 && errno != ENOENT) {
    (void)fprintf(stderr,
                  "Warning: Delete failed for '%s': %s\n",
                  fpath,
                  strerror(errno));
  }

  return 0;
}

#define MAX_DFT_OPEN_FDS 64
bool rm_rf(const char *path) {
  if (path == NULL || *path == '\0') {
    return true;
  }

  if (nftw(path, unlink_cb, MAX_DFT_OPEN_FDS, FTW_DEPTH | FTW_PHYS) != 0) {
    if (errno == ENOENT) {
      return true;
    }
    return false;
  }

  return true;
}
#undef MAX_DFT_OPEN_FDS

#define K_MD5_DIGEST_LENGTH 16
void hash_string_to_bytes(const char *str, uint8_t *out_bytes) {
  if (!str) {
    (void)memset(out_bytes, 0, K_MD5_DIGEST_LENGTH);
    return;
  }
  GChecksum *checksum = g_checksum_new(G_CHECKSUM_MD5);
  g_checksum_update(checksum, (const guchar *)str, -1);

  gsize digest_len = K_MD5_DIGEST_LENGTH;
  g_checksum_get_digest(checksum, out_bytes, &digest_len);
  g_checksum_free(checksum);
}
#undef K_MD5_DIGEST_LENGTH

gchar *hash_cache_key(const CacheKey *key) {
  GChecksum *checksum = g_checksum_new(G_CHECKSUM_MD5);
  g_checksum_update(checksum, (const guchar *)key, sizeof(CacheKey));
  gchar *hash_str = g_strdup(g_checksum_get_string(checksum));
  g_checksum_free(checksum);
  return hash_str;
}

int compare_strings_wrapper(gconstpointer first_pointer,
                            gconstpointer second_pointer) {
  return strcmp((const char *)first_pointer, (const char *)second_pointer);
}

gchar *serialize_map_for_hashing(GHashTable *map) {
  if (map == NULL || g_hash_table_size(map) == 0) {
    return g_strdup("");
  }

  GString *builder_object = g_string_new("");

  GList *keys = g_hash_table_get_keys(map);
  keys = g_list_sort(keys, (GCompareFunc)compare_strings_wrapper);

  for (const GList *list_node = keys; list_node != NULL;
       list_node = list_node->next) {
    const char *current_key = (const char *)list_node->data;
    const char *current_val =
        (const char *)g_hash_table_lookup(map, current_key);

    if (current_val != NULL) {
      g_string_append_printf(
          builder_object, "%s=%s;", current_key, current_val);
    }
  }

  g_list_free(keys);
  return g_string_free(builder_object, FALSE);
}

#define K_ALPHA_OPAQUE 0xFF
#define K_HEXADECIMAL_BASE 16
#define K_ALPHA_CHANNEL_SHIFT 8
guint32 parse_hex_color(const char *hex_str) {
  if (hex_str[0] == '#') {
    hex_str++;
  }

  uint32_t color_val = (uint32_t)strtoul(hex_str, NULL, K_HEXADECIMAL_BASE);

  return (color_val << K_ALPHA_CHANNEL_SHIFT) | K_ALPHA_OPAQUE;
}
#undef K_ALPHA_OPAQUE
#undef K_HEXADECIMAL_BASE
#undef K_ALPHA_CHANNEL_SHIFT

size_t count_lines(const gchar *str) {
  if (!str) {
    return 0;
  }

  size_t count = 1;
  for (const gchar *cursor = str; *cursor; cursor++) {
    if (*cursor == '\n') {
      count++;
    }
  }
  return count;
}

void *signal_monitor_thread_func(void *arg) {
  char dummy = '\0';

  AppState *state = (AppState *)arg;
  while (read(global_signal_pipe[0], &dummy, 1) > 0) {
    if (atomic_load_explicit(&state->exit_requested, memory_order_acquire)) {
      continue;
    }
    atomic_store_explicit(&state->exit_requested, true, memory_order_release);

    (void)pthread_mutex_lock(&state->audio_state_mutex);
    bool has_audio = (state->audio_state.device.pContext != NULL);
    (void)pthread_mutex_unlock(&state->audio_state_mutex);

    if (has_audio) {
      ma_device_stop(&state->audio_state.device);
    }
  }

  return NULL;
}

void app_signal_handler(int signum, siginfo_t *info, void *context) {
  (void)signum;
  (void)info;
  (void)context;
  if (global_signal_pipe[1] != -1) {
    char dummy = 's';
    ssize_t bytes_written = write(global_signal_pipe[1], &dummy, 1);
    (void)bytes_written;
  }
}

void app_resize_handler(int signum, siginfo_t *info, void *context) {
  (void)signum;
  (void)info;
  (void)context;
  if (global_signal_handler_state_ptr) {
    atomic_store_explicit(&global_signal_handler_state_ptr->terminal_resized,
                          true,
                          memory_order_release);
  }
}