/*
	ALICE SOFT SYSTEM 1 for Win32

	[ AGS - gm3 loader ]
*/

#include "ags.h"
#include <string.h>

CG AGS::load_gm3(const std::vector<uint8_t>& data, int transparent)
{
	// ヘッダ取得
	uint16 tmp = (data[0x30] | (data[0x31] << 8)) - 0x8000;
	int sx = tmp % 80;
	int sy = tmp / 80;
	int width = data[0x32] | (data[0x33] << 8);
	int height = data[0x34] | (data[0x35] << 8);
	uint8 base = 0;

	// Zコマンドの処理
	if(palette_bank != -1) {
		base = (palette_bank & 0x0f) << 4;
	}

	// GM3展開
	CG cg(sx * 8, sy * 2, width * 8, height * 2);
	if (transparent >= 0) {
		SDL_SetColorKey(cg.surface(), SDL_TRUE, transparent | base);
	}
	uint8 cgdata[3][80][3];
	int p = 0x36;
	memset(cgdata, 0, sizeof(cgdata));

	for(int y = 0; y < height; y++) {
		for(int pl = 0; pl < 3; pl++) {
			int x = 0;
			while(x < width) {
				uint8 d1 = data[p++];
				if(d1 == 0x0) {
					uint8 d2 = data[p++];
					if(d2 < 0x80) {
						uint8 d3 = data[p++];
						for(int i = 0; i < d2; i++) {
							cgdata[pl][x++][0] = d3;
						}
					} else {
						uint8 d3 = cgdata[pl][x + 1][2];
						for(int i = 0; i < d2 - 0x80; i++) {
							cgdata[pl][x++][0] = d3;
						}
					}
				} else if(d1 == 0x1) {
					cgdata[pl][x++][0] = data[p++];
				} else if(0x2 <= d1 && d1 <= 0x7) {
					uint8 d2 = data[p++];
					for(int i = 0; i < d1; i++) {
						cgdata[pl][x++][0] = d2;
					}
				} else if(0x8 <= d1 && d1 <= 0xd) {
					uint8 d2 = cgdata[pl][x + 1][2];
					for(int i = 0; i < d1 - 6; i++) {
						cgdata[pl][x++][0] = d2;
					}
				} else if(d1 == 0xe) {
					uint8 d2 = data[p++];
					for(int i = 0; i < d2; i++) {
						cgdata[pl][x][0] = cgdata[2][x][0];
						x++;
					}
				} else if(d1 == 0xf) {
					uint8 d2 = data[p++];
					if(d2 < 0x80) {
						for(int i = 0; i < d2; i++) {
							cgdata[pl][x][0] = cgdata[0][x][0];
							x++;
						}
					} else {
						for(int i = 0; i < d2 - 0x80; i++) {
							cgdata[pl][x][0] = cgdata[1][x][0];
							x++;
						}
					}
				} else {
					cgdata[pl][x++][0] = d1;
				}
			}
		}

		// Transfer to the surface
		for (int x = 0; x < width; x++) {
			for (int pl = 0; pl < 3; pl++) {
				cgdata[pl][x][2] = cgdata[pl][x][1];
				cgdata[pl][x][1] = cgdata[pl][x][0];
			}
			uint8 b0, b1, b2, c[8];
			b0 = cgdata[0][x][0];
			b1 = cgdata[1][x][0];
			b2 = cgdata[2][x][0];
			c[0] = ((b0 >> 7) & 1) | ((b1 >> 6) & 2) | ((b2 >> 5) & 4);
			c[1] = ((b0 >> 6) & 1) | ((b1 >> 5) & 2) | ((b2 >> 4) & 4);
			c[2] = ((b0 >> 5) & 1) | ((b1 >> 4) & 2) | ((b2 >> 3) & 4);
			c[3] = ((b0 >> 4) & 1) | ((b1 >> 3) & 2) | ((b2 >> 2) & 4);
			c[4] = ((b0 >> 3) & 1) | ((b1 >> 2) & 2) | ((b2 >> 1) & 4);
			c[5] = ((b0 >> 2) & 1) | ((b1 >> 1) & 2) | ((b2     ) & 4);
			c[6] = ((b0 >> 1) & 1) | ((b1     ) & 2) | ((b2 << 1) & 4);
			c[7] = ((b0     ) & 1) | ((b1 << 1) & 2) | ((b2 << 2) & 4);

			uint8_t* dest0 = surface_line(cg.surface(), y * 2) + x * 8;
			uint8_t* dest1 = dest0 + cg.surface()->pitch;
			for (int i = 0; i < 8; i++) {
				dest0[i] = dest1[i] = c[i] | base;
			}
		}
	}

	return cg;
}