#include "../../test.h"
#include "../../vm.h"
#include "devices.h"
#include <SDL2/SDL.h>

#include <stdint.h>
#include <string.h>

#define MAX_SRC_SIZE 16384

static DeviceOps screen_ops = {.open = screen_open,
                               .read = screen_read,
                               .write = screen_write,
                               .close = screen_close,
                               .ioctl = NULL};

static DeviceOps mouse_ops = {.open = mouse_open,
                              .read = mouse_read,
                              .write = mouse_write,
                              .close = mouse_close,
                              .ioctl = NULL};

static DeviceOps keyboard_ops = {.open = keyboard_open,
                                 .read = keyboard_read,
                                 .write = keyboard_write,
                                 .close = keyboard_close,
                                 .ioctl = NULL};

static ScreenDeviceData screen_data = {0};
static MouseDeviceData mouse_data = {0};
static KeyboardDeviceData keyboard_data = {0};

void compileFile(const char *path, VM *vm) {
  FILE *f = fopen(path, "rb");
  if (!f) {
    perror("fopen");
    exit(1);
  }

  static char source[MAX_SRC_SIZE + 1];

  fseek(f, 0, SEEK_END);
  long len = ftell(f);
  fseek(f, 0, SEEK_SET);
  if (len >= MAX_SRC_SIZE) {
    perror("source is larget than buffer");
    exit(1);
  }
  size_t read = fread(source, 1, len, f);
  source[read] = '\0';
  fclose(f);
}

void repl(VM *vm) {
  char line[1024];
  for (;;) {
    printf("> ");

    if (!fgets(line, sizeof(line), stdin)) {
      printf("\n");
      break;
    }
    /* reset the code counter to 0 */
    vm->cp = 0;
    vm->sp = 0;
    vm->pc = 0;
    vm->mp = 0;

    /* assemble(line, vm); */
    while (step_vm(vm))
      ;
  }
  exit(0);
}

enum FlagType {
  FLAG_NONE = 0,
  FLAG_DEV_MODE = 1,
  FLAG_TEST_MODE = 2,
  FLAG_DUMP_ROM = 4,
  FLAG_GUI_MODE = 8,
};

#define MAX_INPUT_FILES 16 /* Adjust based on your system's constraints */

struct CompilerConfig {
  uint32_t flags;
  char *input_files[MAX_INPUT_FILES];
  int input_file_count;
};

int parse_arguments(int argc, char *argv[], struct CompilerConfig *config) {
  int i;

  /* Initialize config */
  config->flags = 0;
  config->input_file_count = 0;

  /* Zero out input files array for safety */
  for (i = 0; i < MAX_INPUT_FILES; i++) {
    config->input_files[i] = NULL;
  }

  for (i = 1; i < argc; i++) {
    if (argv[i][0] == '-') {
      /* Long and short flag handling */
      if (strcmp(argv[i], "-d") == 0 || strcmp(argv[i], "--dev") == 0) {
        config->flags |= FLAG_DEV_MODE;
      } else if (strcmp(argv[i], "-g") == 0 || strcmp(argv[i], "--gui") == 0) {
        config->flags |= FLAG_GUI_MODE;
      } else if (strcmp(argv[i], "-t") == 0 || strcmp(argv[i], "--test") == 0) {
        config->flags |= FLAG_TEST_MODE;
      } else if (strcmp(argv[i], "-o") == 0 ||
                 strcmp(argv[i], "--dump-rom") == 0) {
        config->flags |= FLAG_DUMP_ROM;
      } else {
        fprintf(stderr, "Unknown flag: %s\n", argv[i]);
        return -1;
      }
    } else if (strstr(argv[i], ".ul") != NULL) {
      /* Collect input files */
      if (config->input_file_count >= MAX_INPUT_FILES) {
        fprintf(stderr, "Too many input files. Maximum is %d\n",
                MAX_INPUT_FILES);
        return -1;
      }
      config->input_files[config->input_file_count++] = argv[i];
    }
  }

  return 0;
}

void register_sdl_devices(VM *vm) {
  screen_data.vm = vm;
  screen_data.width = 640;
  screen_data.height = 480;
  screen_data.framebuffer_size = 640 * 480;
  screen_data.framebuffer_pos = vm->mp;
  vm->mp += screen_data.framebuffer_size / 4; /* advance memory pointer */

  vm_register_device(vm, "/dev/screen/0", "screen", &screen_data, &screen_ops);

  mouse_data.x = 0;
  mouse_data.y = 0;
  mouse_data.btn1 = 0;
  mouse_data.btn2 = 0;
  mouse_data.btn3 = 0;
  mouse_data.btn4 = 0;

  vm_register_device(vm, "/dev/mouse/0", "mouse", &mouse_data, &mouse_ops);

  keyboard_data.keys = SDL_GetKeyboardState(&keyboard_data.key_count);

  vm_register_device(vm, "/dev/keyboard/0", "keyboard", &keyboard_data,
                     &keyboard_ops);
}

int main(int argc, char *argv[]) {
  struct CompilerConfig config = {0};

  if (parse_arguments(argc, argv, &config) != 0) {
    fprintf(stderr, "Usage: %s [-d] [-t] [-g] [-o] <file1.ul> [file2.ul] ...\n",
            argv[0]);
    return 64;
  }

  VM vm = {0};
  if (config.input_file_count == 0) {
    repl(&vm);
  } else {
    if (config.flags & FLAG_TEST_MODE) {
      compile_internal_test(config.input_files[0], &vm);
    } else {
      int j;
      for (j = 0; j < config.input_file_count; j++) {
        compileFile(config.input_files[j], &vm);
      }
    }

    if (config.flags & FLAG_DUMP_ROM) {
      FILE *file = fopen("memory_dump.bin", "wb");
      if (!file) {
        perror("Failed to open file");
        return EXIT_FAILURE;
      }

      size_t code_written = fwrite(vm.code, 1, CODE_SIZE, file);
      if (code_written != CODE_SIZE) {
        fprintf(stderr, "Incomplete code write: %zu bytes written out of %u\n",
                code_written, CODE_SIZE);
        fclose(file);
        return EXIT_FAILURE;
      }

      size_t memory_written = fwrite(vm.memory, 1, MEMORY_SIZE, file);
      if (memory_written != MEMORY_SIZE) {
        fprintf(stderr,
                "Incomplete memory write: %zu bytes written out of %u\n",
                memory_written, MEMORY_SIZE);
        fclose(file);
        return EXIT_FAILURE;
      }

      fclose(file);
    }
  }
  bool running = true;

  if (config.flags & FLAG_GUI_MODE) {
    uint32_t i;
    register_sdl_devices(&vm);
    while (running) {
      for (i = 0; i < vm.dc; i++) {
        Device *dev = &vm.devices[i];
        if (strcmp(dev->type, "mouse") == 0) {
          MouseDeviceData *mouse = (MouseDeviceData *)dev->data;
          SDL_PumpEvents();
          SDL_Event event;
          while (SDL_PollEvent(&event)) {
            switch (event.type) {
            case SDL_QUIT:
              running = false;
              break;
            case SDL_MOUSEMOTION:
              mouse->x = event.motion.x;
              mouse->y = event.motion.y;
              break;
            case SDL_MOUSEBUTTONDOWN:
              if (event.button.button == SDL_BUTTON_LEFT)
                mouse->btn1 = 1;
              if (event.button.button == SDL_BUTTON_RIGHT)
                mouse->btn2 = 1;
              if (event.button.button == SDL_BUTTON_MIDDLE)
                mouse->btn3 = 1;
              if (event.button.button == SDL_BUTTON_X1)
                mouse->btn4 = 1;
              break;
            case SDL_MOUSEBUTTONUP:
              if (event.button.button == SDL_BUTTON_LEFT)
                mouse->btn1 = 0;
              if (event.button.button == SDL_BUTTON_RIGHT)
                mouse->btn2 = 0;
              if (event.button.button == SDL_BUTTON_MIDDLE)
                mouse->btn3 = 0;
              if (event.button.button == SDL_BUTTON_X1)
                mouse->btn4 = 0;
              break;
            }
          }
        }
      }

      step_vm(&vm);

      for (i = 0; i < vm.dc; i++) {
        Device *dev = &vm.devices[i];
        if (strcmp(dev->type, "screen") == 0) {
          ScreenDeviceData *screen = (ScreenDeviceData *)dev->data;
          if (screen->texture && screen->renderer) {
            SDL_UpdateTexture(screen->texture, NULL,
                              &vm.memory[screen->framebuffer_pos],
                              screen->width * sizeof(uint32_t));

            SDL_RenderClear(screen->renderer);

            SDL_Rect output_rect;
            SDL_RenderGetViewport(screen->renderer, &output_rect);
            float scale_x = (float)output_rect.w / screen->width;
            float scale_y = (float)output_rect.h / screen->height;
            float scale = SDL_min(scale_x, scale_y);

            SDL_Rect dstrect = {
                (int)((output_rect.w - screen->width * scale) / 2),
                (int)((output_rect.h - screen->height * scale) / 2),
                (int)(screen->width * scale), (int)(screen->height * scale)};

            SDL_RenderCopy(screen->renderer, screen->texture, NULL, &dstrect);
            SDL_RenderPresent(screen->renderer);
          }
          break;
        }
      }
    }
  } else {
    while (running) {
      running = step_vm(&vm);
    }
  }

  return 0;
}