#include <stdio.h>
#include <stdlib.h>
#include <mupdf/fitz.h>
#define IMGL3W_IMPL
#include "opengl3_loader.h"
#define GLFW_INCLUDE_NONE
#include <GLFW/glfw3.h>
#if defined(__SWITCH__)
#include <switch.h>

extern "C" void userAppInit()
{
  socketInitializeDefault();
  nxlinkStdio();
  appletSetWirelessPriorityMode(AppletWirelessPriorityMode_OptimizedForWlan);
  plInitialize(PlServiceType_User);
}

extern "C" void userAppExit()
{
  plExit();
  socketExit();
}
#endif

const char *vertexShaderSource = "#version 330 core\n"
    "layout (location = 0) in vec3 aPos;\n"
    "void main()\n"
    "{\n"
    "   gl_Position = vec4(aPos.x, aPos.y, aPos.z, 1.0);\n"
    "}\0";

static const GLfloat vertices[] = {
	0.f, 0.f,
	1.f, 0.f,
	1.f, 1.f,
	0.f, 1.f,
};

struct texture
{
  GLuint id;
  int x, y, w, h;
};

void ui_texture_from_pixmap(struct texture *tex, fz_pixmap *pix)
{
  if (!tex->id)
    glGenTextures(1, &tex->id);
  glBindTexture(GL_TEXTURE_2D, tex->id);
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

  tex->x = pix->x;
  tex->y = pix->y;
  tex->w = pix->w;
  tex->h = pix->h;

  glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
  glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, tex->w, tex->h, 0, GL_RGBA, GL_UNSIGNED_BYTE, pix->samples);
  glBindTexture(GL_TEXTURE_2D, 0);
}

void ui_draw_image(struct texture *tex, float x, float y)
{
}

static void die(const char *msg)
{
  fprintf(stderr, "%s\n", msg);
  exit(1);
}

// Main code
int main(int argc, char *argv[])
{
  if (argc < 2)
  {
    fprintf(stderr, "usage: example input-file\n");
    return 0;
  }
  char *input = argv[1];

  if (!glfwInit())
    die("init glfw failed");

  glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
  glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 2);
  glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);

  /* Create a context to hold the exception stack and various caches. */
  fz_document *doc;
  fz_context *ctx = fz_new_context(NULL, NULL, FZ_STORE_UNLIMITED);
  if (!ctx)
    die("cannot create mupdf context");

  fz_try(ctx)
      fz_register_document_handlers(ctx);
  fz_catch(ctx)
  {
    fprintf(stderr, "cannot register document handlers\n");
    fz_drop_context(ctx);
    return EXIT_FAILURE;
  }

  fz_try(ctx)
      doc = fz_open_document(ctx, input);
  fz_catch(ctx)
  {
    fprintf(stderr, "cannot open document\n");
    fz_drop_context(ctx);
    return EXIT_FAILURE;
  }

  struct texture page_tex = {0};
  int page_count = fz_count_pages(ctx, doc);
  printf("page_count %d\n", page_count);

  fz_matrix ctm = fz_scale(1.f, 1.f);
  fz_pixmap *pix = fz_new_pixmap_from_page_number(ctx, doc, 0, ctm, fz_device_rgb(ctx), 1);
  ui_texture_from_pixmap(&page_tex, pix);

  // Create window with graphics context
  GLFWwindow *window = glfwCreateWindow(pix->w, pix->h, "mupdf", NULL, NULL);
  if (!window)
  {
    glfwTerminate();
    return -1;
  }
  glfwMakeContextCurrent(window);
  imgl3wInit2(glfwGetProcAddress);
  glfwSwapInterval(1);
  glfwSetTime(0);

  int fbw = 0, fbh = 0;
  // Main loop
  while (!glfwWindowShouldClose(window))
  {
    glfwGetFramebufferSize(window, &fbw, &fbh);
    glViewport(0, 0, fbw, fbh);

    ui_draw_image(&page_tex, pix->w, pix->h);

    glfwSwapBuffers(window);
    glfwWaitEvents();
  }

  glfwDestroyWindow(window);
  glfwTerminate();

  /* Clean up. */
  fz_drop_pixmap(ctx, pix);
  fz_drop_document(ctx, doc);
  fz_drop_context(ctx);

  return 0;
}