// Copyright 2021 David Robillard <d@drobilla.net>
// SPDX-License-Identifier: ISC

// Tests basic OpenGL support

#undef NDEBUG

#include "test_utils.h"

#include "pugl/gl.h"
#include "pugl/pugl.h"

#include <assert.h>
#include <stdbool.h>

typedef struct {
  PuglWorld*      world;
  PuglView*       view;
  PuglTestOptions opts;
  bool            exposed;
} PuglTest;

static void
onConfigure(PuglView* const view, const PuglConfigureEvent* const event)
{
  (void)view;

  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();

  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();

  glViewport(0, 0, (int)event->width, (int)event->height);
}

static void
onExpose(PuglView* const view, const PuglExposeEvent* const event)
{
  (void)view;
  (void)event;

  glClearColor(0.0f, 0.0f, 1.0f, 1.0f);
  glClear(GL_COLOR_BUFFER_BIT);
}

static PuglStatus
onEvent(PuglView* const view, const PuglEvent* const event)
{
  PuglTest* const test = (PuglTest*)puglGetHandle(view);

  if (test->opts.verbose) {
    printEvent(event, "Event: ", true);
  }

  switch (event->type) {
  case PUGL_CONFIGURE:
    onConfigure(view, &event->configure);
    break;

  case PUGL_EXPOSE:
    onExpose(view, &event->expose);
    test->exposed = true;
    break;

  default:
    break;
  }

  return PUGL_SUCCESS;
}

int
main(int argc, char** argv)
{
  PuglWorld* const      world = puglNewWorld(PUGL_PROGRAM, 0);
  PuglView* const       view  = puglNewView(world);
  const PuglTestOptions opts  = puglParseTestOptions(&argc, &argv);
  PuglTest              test  = {world, view, opts, false};

  // Set up and show view
  puglSetClassName(test.world, "PuglTest");
  puglSetWindowTitle(test.view, "Pugl OpenGL Test");
  puglSetHandle(test.view, &test);
  puglSetBackend(test.view, puglGlBackend());
  puglSetEventFunc(test.view, onEvent);
  puglSetSizeHint(test.view, PUGL_DEFAULT_SIZE, 512, 512);
  puglShow(test.view);

  // Enter OpenGL context as if setting things up
  puglEnterContext(test.view);

  const PuglGlFunc createProgram = puglGetProcAddress("glCreateProgram");
  assert(createProgram);

  puglLeaveContext(test.view);

  // Drive event loop until the view gets exposed
  while (!test.exposed) {
    puglUpdate(test.world, -1.0);
  }

  // Tear down
  puglFreeView(test.view);
  puglFreeWorld(test.world);

  return 0;
}
