#ifdef _WIN32
#include <windows.h>
#endif

#include "wota.h"

#define STB_DS_IMPLEMENTATION
#include "stb_ds.h"

#include "cell.h"
#include "cell_internal.h"
#include "cJSON.h"

#define BOOTSTRAP_MACH "internal/bootstrap.mach"
#define BOOTSTRAP_SRC  "internal/bootstrap.cm"
#define CELL_SHOP_DIR ".cell"
#define CELL_CORE_DIR "packages/core"

#include <math.h>
#include <signal.h>
#include <unistd.h>
#include <sys/stat.h>

/* Test suite declarations */
int run_c_test_suite(JSContext *ctx);
static int run_test_suite(size_t heap_size);

cell_rt *root_cell = NULL;
static char *shop_path = NULL;
static char *core_path = NULL;
static JSRuntime *g_runtime = NULL;

// Get the home directory
static const char* get_home_dir(void) {
  const char *home = getenv("HOME");
  if (!home) {
    home = getenv("USERPROFILE"); // Windows fallback
  }
  return home;
}

// Resolve shop_path and core_path
// core: --core flag > CELL_CORE env > derived from shop
// shop: --shop flag > CELL_SHOP env > ~/.cell
int find_cell_shop(const char *shop_override, const char *core_override)
{
  // Resolve shop_path
  if (shop_override) {
    shop_path = strdup(shop_override);
  } else {
    const char *env = getenv("CELL_SHOP");
    if (env) {
      shop_path = strdup(env);
    } else {
      const char *home = get_home_dir();
      if (!home && !core_override && !getenv("CELL_CORE")) {
        printf("ERROR: Could not determine home directory. Set HOME environment variable.\n");
        return 0;
      }
      if (home) {
        size_t path_len = strlen(home) + strlen("/" CELL_SHOP_DIR) + 1;
        shop_path = malloc(path_len);
        if (shop_path)
          snprintf(shop_path, path_len, "%s/" CELL_SHOP_DIR, home);
      }
    }
  }

  // Resolve core_path
  if (core_override) {
    core_path = strdup(core_override);
  } else {
    const char *env = getenv("CELL_CORE");
    if (env) {
      core_path = strdup(env);
    } else if (shop_path) {
      size_t core_len = strlen(shop_path) + strlen("/" CELL_CORE_DIR) + 1;
      core_path = malloc(core_len);
      if (core_path)
        snprintf(core_path, core_len, "%s/" CELL_CORE_DIR, shop_path);
    }
  }

  if (!core_path) {
    printf("ERROR: No core path. Use --core <path> or set CELL_CORE.\n");
    return 0;
  }

  // Check if the core directory exists
  struct stat st;
  if (stat(core_path, &st) != 0 || !S_ISDIR(st.st_mode)) {
    printf("ERROR: Core not found at %s\n", core_path);
    return 0;
  }

  return 1;
}

// Load a file from the core directory
static char* load_core_file(const char *filename, size_t *out_size) {
  if (!core_path) return NULL;

  size_t path_len = strlen(core_path) + 1 + strlen(filename) + 1;
  char *full_path = malloc(path_len);
  if (!full_path) return NULL;

  snprintf(full_path, path_len, "%s/%s", core_path, filename);

  FILE *fh = fopen(full_path, "rb");
  free(full_path);

  if (!fh) return NULL;

  fseek(fh, 0, SEEK_END);
  long file_size = ftell(fh);
  fseek(fh, 0, SEEK_SET);

  char *data = malloc(file_size + 1);
  if (!data) {
    fclose(fh);
    return NULL;
  }

  if (fread(data, 1, file_size, fh) != (size_t)file_size) {
    free(data);
    fclose(fh);
    return NULL;
  }

  fclose(fh);
  data[file_size] = 0;

  if (out_size) *out_size = file_size;
  return data;
}

// Get the core path for use by scripts
const char* cell_get_core_path(void) {
  return core_path;
}

void actor_disrupt(cell_rt *crt)
{
  crt->disrupt = 1;
  if (crt->state != ACTOR_RUNNING)
    actor_free(crt);
}

JSValue js_os_use(JSContext *js);
JSValue js_math_use(JSContext *js);
JSValue js_json_use(JSContext *js);
JSValue js_nota_use(JSContext *js);
JSValue js_wota_use(JSContext *js);

void script_startup(cell_rt *prt)
{
  if (!g_runtime) {
    g_runtime = JS_NewRuntime();
  }
  JSContext *js = JS_NewContext(g_runtime);
  JS_SetInterruptHandler(js, (JSInterruptHandler *)actor_interrupt_cb, prt);

  JS_SetContextOpaque(js, prt);
  prt->context = js;

  /* Register all GCRef fields so the Cheney GC can relocate them. */
  JS_AddGCRef(js, &prt->idx_buffer_ref);
  JS_AddGCRef(js, &prt->on_exception_ref);
  JS_AddGCRef(js, &prt->message_handle_ref);
  JS_AddGCRef(js, &prt->unneeded_ref);
  JS_AddGCRef(js, &prt->actor_sym_ref);
  prt->idx_buffer_ref.val = JS_NULL;
  prt->on_exception_ref.val = JS_NULL;
  prt->message_handle_ref.val = JS_NULL;
  prt->unneeded_ref.val = JS_NULL;
  prt->actor_sym_ref.val = JS_NULL;

  cell_rt *crt = JS_GetContextOpaque(js);
  JS_FreeValue(js, js_blob_use(js));

  // Load pre-compiled bootstrap bytecode (.mach)
  size_t boot_size;
  char *boot_data = load_core_file(BOOTSTRAP_MACH, &boot_size);
  if (!boot_data) {
    printf("ERROR: Could not load bootstrap from %s!\n", core_path);
    return;
  }

  // Create hidden environment
  JSValue hidden_env = JS_NewObject(js);
  JS_SetPropertyStr(js, hidden_env, "os", js_os_use(js));
  JS_SetPropertyStr(js, hidden_env, "json", js_json_use(js));
  JS_SetPropertyStr(js, hidden_env, "nota", js_nota_use(js));
  JS_SetPropertyStr(js, hidden_env, "wota", js_wota_use(js));

  crt->actor_sym_ref.val = JS_NewObject(js);
  JS_SetPropertyStr(js, hidden_env, "actorsym", JS_DupValue(js, crt->actor_sym_ref.val));

  // Always set init (even if null)
  if (crt->init_wota) {
    JS_SetPropertyStr(js, hidden_env, "init", wota2value(js, crt->init_wota));
    free(crt->init_wota);
    crt->init_wota = NULL;
  } else {
    JS_SetPropertyStr(js, hidden_env, "init", JS_NULL);
  }

  // Set args to null for actor spawn (not CLI mode)
  JS_SetPropertyStr(js, hidden_env, "args", JS_NULL);

  if (core_path)
    JS_SetPropertyStr(js, hidden_env, "core_path", JS_NewString(js, core_path));
  JS_SetPropertyStr(js, hidden_env, "shop_path",
    shop_path ? JS_NewString(js, shop_path) : JS_NULL);

  // Stone the environment
  hidden_env = JS_Stone(js, hidden_env);

  // Run through MACH VM
  crt->state = ACTOR_RUNNING;
  JSValue v = JS_RunMachBin(js, (const uint8_t *)boot_data, boot_size, hidden_env);
  free(boot_data);
  uncaught_exception(js, v);
  crt->state = ACTOR_IDLE;
  set_actor_state(crt);
}

static void signal_handler(int sig)
{
  const char *str = NULL;
#ifndef TARGET_PLAYDATE
  switch (sig) {
    case SIGABRT: str = "SIGABRT"; break;
    case SIGFPE:  str = "SIGFPE";  break;
    case SIGILL:  str = "SIGILL";  break;
    case SIGINT:  str = "SIGINT";  break;
    case SIGSEGV: str = "SIGSEGV"; break;
    case SIGTERM: str = "SIGTERM"; break;
  }
#endif
  if (!str) return;

  exit_handler();
}

/* Run the C test suite with minimal runtime setup */
static int run_test_suite(size_t heap_size)
{
  JSRuntime *rt = JS_NewRuntime();
  if (!rt) {
    printf("Failed to create JS runtime\n");
    return 1;
  }

  JSContext *ctx = JS_NewContextWithHeapSize(rt, heap_size);
  if (!ctx) {
    printf("Failed to create JS context\n");
    JS_FreeRuntime(rt);
    return 1;
  }

  int result = run_c_test_suite(ctx);

  JS_FreeContext(ctx);
  JS_FreeRuntime(rt);

  return result;
}

static void print_usage(const char *prog)
{
  printf("Usage: %s [options] <program> [args...]\n\n", prog);
  printf("Run a cell program (.ce actor).\n\n");
  printf("Options:\n");
  printf("  --core <path>              Set core path directly (overrides CELL_CORE)\n");
  printf("  --shop <path>              Set shop path (overrides CELL_SHOP)\n");
  printf("  --test [heap_size]         Run C test suite\n");
  printf("  -h, --help                 Show this help message\n");
  printf("\nEnvironment:\n");
  printf("  CELL_CORE                  Core path (default: <shop>/packages/core)\n");
  printf("  CELL_SHOP                  Shop path (default: ~/.cell)\n");
  printf("\nRecompile after changes:  make\n");
  printf("Bootstrap from scratch:  make bootstrap\n");
}

int cell_init(int argc, char **argv)
{
  /* Check for --help flag */
  if (argc >= 2 && (strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--help") == 0)) {
    print_usage(argv[0]);
    return 0;
  }

  /* Check for --test flag to run C test suite */
  if (argc >= 2 && strcmp(argv[1], "--test") == 0) {
    size_t heap_size = 64 * 1024; /* 64KB default */
    if (argc >= 3) {
      heap_size = strtoull(argv[2], NULL, 0);
      /* Round up to power of 2 for buddy allocator */
      size_t p = 1;
      while (p < heap_size) p <<= 1;
      heap_size = p;
    }
    return run_test_suite(heap_size);
  }

  /* Default: run script through bootstrap pipeline */
  int arg_start = 1;
  const char *shop_override = NULL;
  const char *core_override = NULL;

  // Parse flags (order-independent)
  while (arg_start < argc && argv[arg_start][0] == '-') {
    if (strcmp(argv[arg_start], "--shop") == 0) {
      if (arg_start + 1 >= argc) {
        printf("ERROR: --shop requires a path argument\n");
        return 1;
      }
      shop_override = argv[arg_start + 1];
      arg_start += 2;
    } else if (strcmp(argv[arg_start], "--core") == 0) {
      if (arg_start + 1 >= argc) {
        printf("ERROR: --core requires a path argument\n");
        return 1;
      }
      core_override = argv[arg_start + 1];
      arg_start += 2;
    } else {
      break;
    }
  }

  if (arg_start >= argc) {
    print_usage(argv[0]);
    return 1;
  }

  if (!find_cell_shop(shop_override, core_override)) return 1;

  actor_initialize();

  size_t boot_size;
  char *boot_data = load_core_file(BOOTSTRAP_MACH, &boot_size);
  if (!boot_data) {
    printf("ERROR: Could not load bootstrap from %s\n", core_path);
    return 1;
  }

  g_runtime = JS_NewRuntime();
  if (!g_runtime) {
    printf("Failed to create JS runtime\n");
    free(boot_data);
    return 1;
  }
  JSContext *ctx = JS_NewContextWithHeapSize(g_runtime, 16 * 1024 * 1024);
  if (!ctx) {
    printf("Failed to create JS context\n");
    free(boot_data); JS_FreeRuntime(g_runtime);
    return 1;
  }

  /* Create a cell_rt for the CLI context so JS-C bridge functions work */
  cell_rt *cli_rt = calloc(sizeof(*cli_rt), 1);
  cli_rt->mutex = malloc(sizeof(pthread_mutex_t));
  pthread_mutexattr_t mattr;
  pthread_mutexattr_init(&mattr);
  pthread_mutexattr_settype(&mattr, PTHREAD_MUTEX_RECURSIVE);
  pthread_mutex_init(cli_rt->mutex, &mattr);
  cli_rt->msg_mutex = malloc(sizeof(pthread_mutex_t));
  pthread_mutex_init(cli_rt->msg_mutex, &mattr);
  pthread_mutexattr_destroy(&mattr);

  cli_rt->context = ctx;
  JS_SetContextOpaque(ctx, cli_rt);
  JS_SetInterruptHandler(ctx, (JSInterruptHandler *)actor_interrupt_cb, cli_rt);

  JS_AddGCRef(ctx, &cli_rt->idx_buffer_ref);
  JS_AddGCRef(ctx, &cli_rt->on_exception_ref);
  JS_AddGCRef(ctx, &cli_rt->message_handle_ref);
  JS_AddGCRef(ctx, &cli_rt->unneeded_ref);
  JS_AddGCRef(ctx, &cli_rt->actor_sym_ref);
  cli_rt->idx_buffer_ref.val = JS_NULL;
  cli_rt->on_exception_ref.val = JS_NULL;
  cli_rt->message_handle_ref.val = JS_NULL;
  cli_rt->unneeded_ref.val = JS_NULL;
  cli_rt->actor_sym_ref.val = JS_NewObject(ctx);

  root_cell = cli_rt;

  JS_FreeValue(ctx, js_blob_use(ctx));

  JSValue hidden_env = JS_NewObject(ctx);
  JS_SetPropertyStr(ctx, hidden_env, "os", js_os_use(ctx));
  JS_SetPropertyStr(ctx, hidden_env, "core_path", JS_NewString(ctx, core_path));
  JS_SetPropertyStr(ctx, hidden_env, "shop_path",
    shop_path ? JS_NewString(ctx, shop_path) : JS_NULL);
  /* TODO: remove after next 'make regen' — old bootstrap.mach reads these */
  JS_SetPropertyStr(ctx, hidden_env, "emit_qbe", JS_FALSE);
  JS_SetPropertyStr(ctx, hidden_env, "dump_mach", JS_FALSE);
  JS_SetPropertyStr(ctx, hidden_env, "actorsym", JS_DupValue(ctx, cli_rt->actor_sym_ref.val));
  JS_SetPropertyStr(ctx, hidden_env, "json", js_json_use(ctx));
  JS_SetPropertyStr(ctx, hidden_env, "nota", js_nota_use(ctx));
  JS_SetPropertyStr(ctx, hidden_env, "wota", js_wota_use(ctx));
  JS_SetPropertyStr(ctx, hidden_env, "init", JS_NULL);
  JSValue args_arr = JS_NewArray(ctx);
  for (int i = arg_start; i < argc; i++) {
    JSValue str = JS_NewString(ctx, argv[i]);
    JS_ArrayPush(ctx, &args_arr, str);
  }
  JS_SetPropertyStr(ctx, hidden_env, "args", args_arr);
  hidden_env = JS_Stone(ctx, hidden_env);

  JSValue result = JS_RunMachBin(ctx, (const uint8_t *)boot_data, boot_size, hidden_env);
  free(boot_data);

  int exit_code = 0;
  if (JS_IsException(result)) {
    JS_GetException(ctx);
    exit_code = 1;
  } else if (!JS_IsNull(result)) {
    const char *str = JS_ToCString(ctx, result);
    if (str) {
      printf("%s\n", str);
      JS_FreeCString(ctx, str);
    }
  }

  if (scheduler_actor_count() > 0) {
    scheduler_enable_quiescence();
    actor_loop();
    exit_handler();
    exit(0);
  }

  /* No actors spawned — clean up CLI context */
  JS_DeleteGCRef(ctx, &cli_rt->idx_buffer_ref);
  JS_DeleteGCRef(ctx, &cli_rt->on_exception_ref);
  JS_DeleteGCRef(ctx, &cli_rt->message_handle_ref);
  JS_DeleteGCRef(ctx, &cli_rt->unneeded_ref);
  JS_DeleteGCRef(ctx, &cli_rt->actor_sym_ref);
  JS_SetInterruptHandler(ctx, NULL, NULL);

  pthread_mutex_destroy(cli_rt->mutex);
  free(cli_rt->mutex);
  pthread_mutex_destroy(cli_rt->msg_mutex);
  free(cli_rt->msg_mutex);
  free(cli_rt);
  root_cell = NULL;

  JS_FreeContext(ctx);
  JS_FreeRuntime(g_runtime);
  g_runtime = NULL;

  exit_handler();
  return exit_code;
}

int JS_ArrayLength(JSContext *js, JSValue a)
{
  int64_t len;
  JS_GetLength(js, a, &len);
  return len;
}

int js2bool(JSContext *js, JSValue v) { return JS_ToBool(js,v); }
JSValue bool2js(JSContext *js, int b) { return JS_NewBool(js,b); }

JSValue number2js(JSContext *js, double g) { return JS_NewFloat64(js,g); }
double js2number(JSContext *js, JSValue v) {
  double g;
  JS_ToFloat64(js, &g, v);
  if (isnan(g)) g = 0;
  return g;
}

uint64_t cell_random_fit() {
  uint64_t buf;
  randombytes((uint8_t *)&buf, sizeof(buf));
  return buf >> 11;
}

double cell_random() {
  uint64_t buf = cell_random_fit();
  return (double)buf / 9007199254740992.0;
}

void cell_trace_sethook(cell_hook)
{

}

int uncaught_exception(JSContext *js, JSValue v)
{
  (void)v;
  if (!JS_HasException(js))
    return 1;
  /* Error message and backtrace were already printed to stderr
     by JS_ThrowError2 / print_backtrace. Just clear the flag. */
  JS_GetException(js);
  return 0;
}