#include "helpers/function.S"
#include "libs/sdl.S"

#define SCREEN_WIDTH 800
#define SCREEN_HEIGHT 600

// integer-params:  RDI, RSI, RDX, RCX, R8, R9
// caller-saved:    RAX, RCX, RDX, RSI, RDI, R8-R11
// callee-saved:    RBX, RSP, RBP, R12-R15

.section .rodata
  failed_to_create_window:  .string "Window could not be created\nSDL_error: %s\n"
  failed_to_initialize_sdl: .string "SDL could not be initialized\nSDL_error: %s\n"
  greeting:                 .string "Hello, SDL!\n"
  window_title:             .string "snake.s"

.section .text

  function_begin main

    define_local window_handle, 8
    allocate_locals

    // initialize SDL
    mov $SDL_INIT_VIDEO, %rdi
    call SDL_Init@PLT

    // check if initialization was successful
    test %rax, %rax
    jae 1f
      lea failed_to_initialize_sdl(%rip), %rdi
      call _print_sdl_error@PLT
      mov $1, %rax
      function_exit
  1:

    // create a window
    lea window_title(%rip), %rdi
    mov $SDL_WINDOWPOS_UNDEFINED, %rsi
    mov $SDL_WINDOWPOS_UNDEFINED, %rdx
    mov $SCREEN_WIDTH, %rcx
    mov $SCREEN_HEIGHT, %r8
    mov $SDL_WINDOW_SHOWN, %r9
    call SDL_CreateWindow@PLT

    store_local %rax, window_handle

    // check if window creation was successful
    test %rax, %rax
    jne 1f
      lea failed_to_create_window(%rip), %rdi
      call _print_sdl_error@PLT
      mov $1, %rax
      function_exit
  1:

    load_local window_handle, %rdi
    call SDL_DestroyWindow@PLT

    call SDL_Quit@PLT

    lea greeting(%rip), %rdi
    xor %rax, %rax
    call printf@PLT

    xor %rax, %rax

  function_end