#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <assert.h>

#include <raylib.h>

#include <tiffio.h>

#include <lib/lib.h>

#define TAG 50839
#define OFFSET 16
#define ONE_ROW 1

#define bool_t uint8_t
#define FALSE 0
#define TRUE 1

//-----------------------------------------------
// Difference in Time
// Compute the difference between timespec structs
double diff_timespec(struct timespec *time1, struct timespec *time0) {
  return (time1->tv_sec - time0->tv_sec)
      + (time1->tv_nsec - time0->tv_nsec) / 1000000000.0;
}

//-----------------------------------------------
// Color Equal to Background
// Background: zeros in RGB, alpha can be whatever
bool_t color_zero(uint8_t* color1, size_t channels) {
  for (size_t idx = 0; idx < channels; idx++) {
    if (idx == 3) {
      break;
    }
    if (color1[idx] != 0) {
      return FALSE;
    }
  }
  return TRUE;
}

//-----------------------------------------------
// Color Equality
// Determine if two colors are identical
bool_t color_equal(uint8_t* color1, uint8_t* color2, size_t channels) {
  for (size_t idx = 0; idx < channels; idx++) {
    if (color1[idx] != color2[idx]) {
      return FALSE;
    }
  }
  return TRUE;
}

//-----------------------------------------------
// Print out the `channels` length color vector
void print_color(uint8_t* color, size_t channels) {
  for (size_t index = 0; index < channels; index++) {
    printf("%hhu ", color[index]);
  }
  printf("\n");
}

//-----------------------------------------------
// Flood
// Floods a mask from a given set of image to determine the contiguous regions
//  1. Check that the (x,y) is within the picture
//  2. Check if the (x,y) coordinate in the mask is unused
//  3. Check if the (x,y) coordinate in the image is non-background
//  4. Check if the (x,y) coordinate in the image is the same color as the fill color
//  5. If all hold, set the label for the pixel, and check each neighbor
//     Otherwise, stop flooding
bool_t flood(uint8_t* image, uint16_t* mask, size_t width, size_t height, size_t channels, size_t x, size_t y, uint8_t* fill_color, uint16_t label)
{
  if ((x >= width) | (y >= height)) {
    return FALSE;
  }
  size_t coord = x + y*width;
  if (mask[coord] != 0) {
    return FALSE;
  }
  if (color_zero(&(image[coord*channels]), channels)) {
    return FALSE;
  }
  if (color_equal(&(image[coord*channels]), fill_color, channels)) {
    mask[coord] = label;
    flood(image, mask, width, height, channels, x, y+1, fill_color, label);
    flood(image, mask, width, height, channels, x, y-1, fill_color, label);
    flood(image, mask, width, height, channels, x+1, y, fill_color, label);
    flood(image, mask, width, height, channels, x-1, y, fill_color, label);
    return TRUE;
  }
  return FALSE;
}

int main()
{
  //-----------------------------------------------
  //-RAYLIB-INIT
  //-----------------------------------------------
  SetTraceLogLevel(LOG_ERROR);
  SetConfigFlags(FLAG_WINDOW_RESIZABLE);
  const char* gui_title = "Image Manip - Useful for segmentations!";
  InitWindow(SCREEN_WIDTH, SCREEN_HEIGHT, gui_title);
  //-----------------------------------------------

  //-----------------------------------------------
  //-TIFF-IMAGE-OPEN-------------------------------
  //-----------------------------------------------
  TIFF *tif = TIFFOpen("./data/test.tif", "r");
  if (!tif) {
    fprintf(stderr, "Failed to open TIFF file\n");
    return 1;
  }
  //-----------------------------------------------

  //-----------------------------------------------
  //-TIFF-FIND-DIMENSIONS--------------------------
  //-----------------------------------------------
  uint32_t width, height;
  size_t channels = 1;
  TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &width);
  TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &height);
  //-----------------------------------------------
  tmsize_t STRIP_LENGTH = TIFFStripSize(tif);
  tmsize_t STRIP_COUNT = TIFFNumberOfStrips(tif);
  if (width*height*3 == STRIP_LENGTH*STRIP_COUNT) {
    channels = 3;
  } else if (width*height*4 == STRIP_LENGTH*STRIP_COUNT) {
    channels = 4;
  }
  //-----------------------------------------------

  printf("Total Strip Size: %llu\n", STRIP_LENGTH*STRIP_COUNT);
  printf("Total Image Size: %lu  in %hhu channel(s)\n", width*height*channels, channels);
  assert(STRIP_LENGTH*STRIP_COUNT == width*height*channels);

  //-----------------------------------------------
  //-TIFF-LOAD-DATA--------------------------------
  //-----------------------------------------------
  void* buffer = malloc(STRIP_LENGTH*sizeof(uint8_t));
  uint8_t* raster_8 = calloc(width*height*channels,sizeof(uint8_t));
  if (raster_8 == NULL) {
    fprintf(stderr, "Memory allocation error\n");
    TIFFClose(tif);
    return 1;
  }
  for (size_t y = 0; y < STRIP_COUNT; y++) {
    tmsize_t strip_size = TIFFReadRawStrip(tif, y, buffer, STRIP_LENGTH);
    assert(strip_size == STRIP_LENGTH);
    for (size_t x = 0; x < STRIP_LENGTH; x++) {
      raster_8[x + y*STRIP_LENGTH] = ((uint8_t*)buffer)[x];
    }
  }
  free(buffer);
  //-----------------------------------------------

  struct timespec ts_start, ts_end;
  timespec_get(&ts_start, TIME_UTC);
  //-----------------------------------------------
  //-FLOOD-FILL-SEGMENTATION-----------------------
  //-CONTIGUOUS-REGION-FINDING---------------------
  //-----------------------------------------------
  uint16_t starting_label = 1;
  uint16_t *labels = NULL;
  labels = (uint16_t*)calloc(width*height,sizeof(uint16_t));
  if (labels == NULL) {
    fprintf(stderr, "Memory allocation error\n");
    free(raster_8);
    TIFFClose(tif);
    return 1;
  }
  // Flood fill on each pixel
  //  Increase label for each success
  for (size_t y = 0; y < height; y++) {
    for (size_t x = 0; x < width; x++) {
      size_t coord = x + y*width;
      if(flood(raster_8, labels, width, height, channels, x, y, &(raster_8[coord*channels]), starting_label)) {
        starting_label += 1;
      }
    }
  }
  // (When treating this as RGBA, last bits should ensure opaque)
  //  This assumes 4096 (2^12) > labels
  for (size_t y = 0; y < height; y++) {
    for (size_t x = 0; x < width; x++) {
      labels[x + y*width] |= 0xFF000000;
    }
  }
  //-----------------------------------------------
  timespec_get(&ts_end, TIME_UTC);
  printf("Time difference: %.3fms\n", 1000*diff_timespec(&ts_end, &ts_start));
  printf("N_labels: %u\n", starting_label-1);

  uint32_t *raster = NULL;
  //-----------------------------------------------
  //-READ-TIFF-IMAGE-------------------------------
  //-----------------------------------------------
  /*
  raster = (uint32_t*)_TIFFmalloc(width*height*sizeof(uint32_t));
  if (raster == NULL) {
    fprintf(stderr, "Memory allocation error\n");
    free(labels);
    free(raster_8);
    TIFFClose(tif);
    return 1;
  }

  if (!TIFFReadRGBAImage(tif, width, height, raster, 0)) {
    fprintf(stderr, "Failed to read TIFF image\n");
    free(labels);
    free(raster_8);
    _TIFFfree(raster);
    TIFFClose(tif);
    return 1;
  }
  */
  //-----------------------------------------------

  //-----------------------------------------------
  //-RAYLIB-IMAGE-STRUCTURING----------------------
  //-----------------------------------------------
  Image RaylibImage;
  RaylibImage.width  = width;
  RaylibImage.height = height;
  RaylibImage.mipmaps = 1;
  // Use Loaded Image
  RaylibImage.data = raster;
  RaylibImage.format = PIXELFORMAT_UNCOMPRESSED_R8G8B8A8;
  // Use Strip Image Data
  RaylibImage.data = raster_8;
  if (channels == 1) {
    RaylibImage.format = PIXELFORMAT_UNCOMPRESSED_GRAYSCALE;
  } else if (channels == 3) {
    RaylibImage.format = PIXELFORMAT_UNCOMPRESSED_R8G8B8;
  } else if (channels == 4) {
    RaylibImage.format = PIXELFORMAT_UNCOMPRESSED_R8G8B8A8;
  } else {
    assert(0);
  }
  // Use Contiguous Labels
  RaylibImage.data = labels;
  RaylibImage.format = PIXELFORMAT_UNCOMPRESSED_R4G4B4A4;
  //-----------------------------------------------

  // Image to a Texture
  Texture2D RaylibTexture = LoadTextureFromImage(RaylibImage);

  // Scale the image to the viewport
  /// Source Rectangle: Original Size
  Rectangle sourceRec = { 0.0f, 0.0f, (float)width, (float)height };
  /// Destination Rectangle: Transformed Size
  Rectangle destRec = { 0.0f, 0.0f, (float)SCREEN_WIDTH, (float)(SCREEN_HEIGHT-OFFSET) };
  /// Location to begin drawing
  Vector2 origin = { (float)0, (float)-OFFSET };

  // Raylib boilerplate
  SetTargetFPS(60);
  Camera2D camera = { 0 };
  camera.zoom = 1.0f;

  // GUI Loop
  while (!WindowShouldClose()) {
    //-----------------------------------------------
    //-DRAWING---------------------------------------
    //-----------------------------------------------
    BeginDrawing();
    ClearBackground(RAYWHITE);
    BeginMode2D(camera);
    EndMode2D();
    DrawText("Image Manip", 0, 0, OFFSET, DARKGRAY);
    DrawTexturePro(RaylibTexture, sourceRec, destRec, origin, (float)0,
                   RAYWHITE);
    /*
    uint32_t x = 0x49, y = 0x4A;
    uint32_t dx = 0x69 - x, dy = 0x6E - y;
    x = (SCREEN_WIDTH*x)/width;
    y = SCREEN_HEIGHT-((SCREEN_HEIGHT-OFFSET)*y)/height;
    dx = (SCREEN_WIDTH*dx)/width;
    dy = SCREEN_HEIGHT-((SCREEN_HEIGHT-OFFSET)*dy)/height;
    DrawRectangleGradientH(x, y, dx, dy, BLUE, PURPLE);
    */
    EndDrawing();
    //-----------------------------------------------
  }

  if (labels != NULL) {
    free(labels);
  }
  if (raster_8 != NULL) {
    free(raster_8);
  }
  if (raster != NULL) {
    _TIFFfree(raster);
  }
  TIFFClose(tif);

  CloseWindow();
  return 0;
}