#include "../../compiler.h"
#include "../../vm.h"

#define MAX_SRC_SIZE 16384

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);

  compile(source, vm);
}

static 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;

    compile(line, vm);
    while (step_vm(vm));
  }
  exit(0);
}

int main(int argc, char **argv) {
  VM vm = {0};
  vm.frames_size = FRAMES_SIZE;
  vm.return_stack_size = STACK_SIZE;
  vm.stack_size = STACK_SIZE;
  vm.memory_size = MEMORY_SIZE;

  if (argc == 1) {
    repl(&vm);
  } else if (argc == 2) {
    compileFile(argv[1], &vm);
  } else {
    fprintf(stderr, "Usage: %s <file.zrl>\n", argv[0]);
    return 64;
  }

  bool running = true;
  while (running) {
    running = step_vm(&vm);
  }
  return 0;
}