/*
 *	Copyright (c) 2024 Scott Duensing, scott@kangaroopunch.com
 *
 *	Permission is hereby granted, free of charge, to any person obtaining a copy
 *	of this software and associated documentation files (the "Software"), to deal
 *	in the Software without restriction, including without limitation the rights
 *	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 *	copies of the Software, and to permit persons to whom the Software is
 *	furnished to do so, subject to the following conditions:
 *
 *	The above copyright notice and this permission notice shall be included in
 *	all copies or substantial portions of the Software.
 *
 *	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 *	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 *	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 *	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 *	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 *	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 *	SOFTWARE.
 */


#include "bitmap.h"


static int      _MAX_X       = 320;
static int      _MAX_Y       = 200;
static uint32_t _BITMAP_BASE = 0x10000;
static byte     _color       = 255;


char error;


void clear(void) {
	int x;
	int y;

	//***TODO*** Use DMA

	// This is just test code.
	for (y=0; y<_MAX_Y; y++) {
		for (x=0; x<_MAX_X; x++) {
			putpixel(x, y);
		}
		_color++;  // Let it roll over.
	}
}


void defineGraphicsColor(byte slot, byte r, byte g, byte b) {
	byte  mmu = PEEK(MMU_IO_CTRL);  // Get current MMU state.
	byte *write;

	POKE(MMU_IO_CTRL, MMU_IO_PAGE_1);  // Swap I/O page 1 into bank 6.

	write = (byte *)VKY_GR_CLUT_0 + slot * 4;
	*write++ = b;
	*write++ = g;
	*write++ = r;
	*write++ = 0xff;

	POKE(MMU_IO_CTRL, mmu);  // Restore MMU state.
}


void putpixel(int x, int y) {
	uint32_t pixelRAM;
	byte     block;

	// We only map 8k of the bitmap into CPU RAM at once.
	// We use slot 5 for this.  We need to figure out
	// where our pixel lands and bring that into RAM.
	pixelRAM = _BITMAP_BASE + (y * _MAX_X) + x;
	block = pixelRAM / 0x2000;
	POKE(MMU_MEM_BANK_5, block);
	//pixelRAM -= 0x2000 * block;  // Find offset into this block.
	pixelRAM &= 0x1FFF;
	POKE(0xa000 + pixelRAM, _color);
	POKE(MMU_MEM_BANK_5, 5);
}


void resetGraphics(void) {
	byte mmu = PEEK(MMU_IO_CTRL);  // Get current MMU state.
	byte x;
	int  y;

	_MAX_X       = 320;
	_MAX_Y       = 200;
	_BITMAP_BASE = 0x10000;
	_color       = 255;

	POKE(MMU_IO_CTRL, MMU_IO_PAGE_0);  // Swap I/O page 0 into bank 6.

	POKE(VKY_LAYER_CTRL_0, 16);  // Bitmaps on all layers.
	POKE(VKY_LAYER_CTRL_1, 1);   // Bitmaps on all layers.
	POKE(VKY_BM1_CTRL, 0);  // Disable bitmap 1.
	POKE(VKY_BM2_CTRL, 0);  // Disable bitmap 2.

	// Set up bitmap 0.
	POKE(VKY_BM0_CTRL, 1);  // Enable bitmap 0, GLUT 0.
	//POKED(VKY_BM0_ADDR_L, _BITMAP_BASE);  // Location of bitmap data.
	POKE(VKY_BM0_ADDR_L, _BITMAP_BASE & 0xFF);  // Location of bitmap data.
	POKE(VKY_BM0_ADDR_M, (_BITMAP_BASE >> 8) & 0xFF);  // Location of bitmap data.
	POKE(VKY_BM0_ADDR_H, (_BITMAP_BASE >> 16) & 0xFF);  // Location of bitmap data.

	// Set palette to a gradient so there's at least *something*.
	for (x=0; x<=255; x++) defineGraphicsColor(x, x, x, x);

	clear();

	/*
	POKE(MMU_MEM_BANK_5, 8);
	for (y=0; y<8192; y++) POKE(0xa000 + y, 255);
	POKE(MMU_MEM_BANK_5, 5);
	*/

	POKE(MMU_IO_CTRL, mmu);  // Restore MMU state.
}


void setGraphicsColor(byte c) {
	_color = c;
}