// ==========================================================

// KOALA Loader

//

// Design and implementation by

// - Floris van den Berg (flvdberg@wxs.nl)

//

// This file is part of FreeImage 3

//

// COVERED CODE IS PROVIDED UNDER THIS LICENSE ON AN "AS IS" BASIS, WITHOUT WARRANTY

// OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, WITHOUT LIMITATION, WARRANTIES

// THAT THE COVERED CODE IS FREE OF DEFECTS, MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE

// OR NON-INFRINGING. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE COVERED

// CODE IS WITH YOU. SHOULD ANY COVERED CODE PROVE DEFECTIVE IN ANY RESPECT, YOU (NOT

// THE INITIAL DEVELOPER OR ANY OTHER CONTRIBUTOR) ASSUME THE COST OF ANY NECESSARY

// SERVICING, REPAIR OR CORRECTION. THIS DISCLAIMER OF WARRANTY CONSTITUTES AN ESSENTIAL

// PART OF THIS LICENSE. NO USE OF ANY COVERED CODE IS AUTHORIZED HEREUNDER EXCEPT UNDER

// THIS DISCLAIMER.

//

// Use at your own risk!

// ==========================================================

#include "FreeImage.h"

#include "Utilities.h"

// ----------------------------------------------------------

//   Constants + headers

// ----------------------------------------------------------

#ifdef _WIN32

#pragma pack(push, 1)

#else

#pragma pack(1)

#endif

typedef struct tagKOALA {

  BYTE image[8000];   // pixmap image

  BYTE colour1[1000];   // first colourmap (colour 1 and 2)

  BYTE colour2[1000];   // second colourmap (colour 3)

  BYTE background;    // background colour

} koala_t;

struct colour_t {

  int r;

  int g;

  int b;  

};

#ifdef _WIN32

#pragma pack(pop)

#else

#pragma pack()

#endif

// ----------------------------------------------------------

#define CBM_WIDTH  320

#define CBM_HEIGHT 200

// ----------------------------------------------------------

const colour_t c64colours[16] = {

  {   0,   0,   0 },  // Black

  { 255, 255, 255 },  // White

  { 170,  17,  17 },  // Red

  {  12, 204, 204 },  // Cyan

  { 221,  51, 221 },  // Purple

  {  0,  187,  0 }, // Green

  {   0,   0, 204 },  // Blue

  { 255, 255, 140 },  // Yellow

  { 204, 119,  34 },  // Orange

  { 136,  68,   0 },  // Brown

  { 255, 153, 136 },  // Light red

  {  92,  92,  92 },  // Gray 1

  { 170, 170, 170 },  // Gray 2

  { 140, 255, 178 },  // Light green

  {  39, 148, 255 },  // Light blue

  { 196, 196, 196 } // Gray 3

};

// ==========================================================

// Plugin Interface

// ==========================================================

static int s_format_id;

// ==========================================================

// Plugin Implementation

// ==========================================================

const char * DLL_CALLCONV

Format() {

  return "KOALA";

}

const char * DLL_CALLCONV

Description() {

  return "C64 Koala Graphics";

}

const char * DLL_CALLCONV

Extension() {

  return "koa";

}

const char * DLL_CALLCONV

RegExpr() {

  return NULL;

}

static const char * DLL_CALLCONV

MimeType() {

  return "image/x-koala";

}

static BOOL DLL_CALLCONV

Validate(FreeImageIO *io, fi_handle handle) {

  BYTE koala_signature[] = { 0x00, 0x60 };

  BYTE signature[2] = { 0, 0 };

  io->read_proc(signature, 1, sizeof(koala_signature), handle);

  return (memcmp(koala_signature, signature, sizeof(koala_signature)) == 0);

}

static BOOL DLL_CALLCONV

SupportsExportDepth(int depth) {

  return FALSE;

}

static BOOL DLL_CALLCONV 

SupportsExportType(FREE_IMAGE_TYPE type) {

  return FALSE;

}

// ----------------------------------------------------------

FIBITMAP * DLL_CALLCONV

Load(FreeImageIO *io, fi_handle handle, int page, int flags, void *data) {

  if (handle) {

    koala_t image;

    // read the load address

    unsigned char load_address[2];  // highbit, lowbit

    io->read_proc(&load_address, 1, 2, handle);

    // if the load address is correct, skip it. otherwise ignore the load address

    if ((load_address[0] != 0x00) || (load_address[1] != 0x60)) {

      ((BYTE *)&image)[0] = load_address[0];

      ((BYTE *)&image)[1] = load_address[1];

      io->read_proc((BYTE *)&image + 2, 1, 10001 - 2, handle);

    } else {

      io->read_proc(&image, 1, 10001, handle);

    }    

    // build DIB in memory

    FIBITMAP *dib = FreeImage_Allocate(CBM_WIDTH, CBM_HEIGHT, 4);

    if (dib) {

      // write out the commodore 64 color palette

      RGBQUAD *palette = FreeImage_GetPalette(dib);

      for (int i = 0; i < 16; i++) {

        palette[i].rgbBlue  = (BYTE)c64colours[i].b;

        palette[i].rgbGreen = (BYTE)c64colours[i].g;

        palette[i].rgbRed   = (BYTE)c64colours[i].r;

      }

      // write out bitmap data

      BYTE pixel_mask[4]         = { 0xc0, 0x30, 0x0c, 0x03 };

      BYTE pixel_displacement[4] = { 6, 4, 2, 0 };

      int pixel, index, colourindex;

      unsigned char found_color = 0;

      for (int y = 0; y < 200; y++) {

        for (int x = 0; x < 160; x++) {

          // Get value of pixel at (x,y)

          index = (x / 4) * 8 + (y % 8) + (y / 8) * CBM_WIDTH;

          colourindex = (x / 4) + (y / 8) * 40;

          pixel = (image.image[index] & pixel_mask[x % 4]) >> pixel_displacement[x % 4];

          // Retrieve RGB values

          switch (pixel) {

            case 0: // Background

              found_color = image.background;

              break;

            case 1: // Colour 1

              found_color = image.colour1[colourindex] >> 4;

              break;

            case 2: // Colour 2

              found_color = image.colour1[colourindex] & 0xf;

              break;

            case 3: // Colour 3

              found_color = image.colour2[colourindex] & 0xf;

              break;

          };

          *(FreeImage_GetScanLine(dib, CBM_HEIGHT - y - 1) + x) = (found_color << 4) | found_color;

        }

      }

      return dib;

    }

  }

  return NULL;

}

// ==========================================================

//   Init

// ==========================================================

void DLL_CALLCONV

InitKOALA(Plugin *plugin, int format_id) {

  s_format_id = format_id;

  plugin->format_proc = Format;

  plugin->description_proc = Description;

  plugin->extension_proc = Extension;

  plugin->regexpr_proc = RegExpr;

  plugin->open_proc = NULL;

  plugin->close_proc = NULL;

  plugin->pagecount_proc = NULL;

  plugin->pagecapability_proc = NULL;

  plugin->load_proc = Load;

  plugin->save_proc = NULL;

  plugin->validate_proc = Validate;

  plugin->mime_proc = MimeType;

  plugin->supports_export_bpp_proc = SupportsExportDepth;

  plugin->supports_export_type_proc = SupportsExportType;

  plugin->supports_icc_profiles_proc = NULL;

}