#include <SDL.h>
//#define STB_IMAGE_IMPLEMENTATION
//#include "stb_image.h"
#include <string.h>
#include "font.h"

#define VDP_CMD_LOCATE		0
#define VDP_CMD_PRINT		1
#define VDP_CMD_PUTCHAR		2
#define VDP_CMD_SETCHAR		3
#define VDP_CMD_PUTSPRITE	4
#define VDP_CMD_SETSPRITE	5
#define VDP_CMD_FLIP		6
#define VDP_CMD_COLOR		7
#define VDP_CMD_BORDER		8

SDL_Window* sdlWindow = NULL;
SDL_Renderer* sdlRenderer = NULL;
SDL_Texture* sdlTexture = NULL;
SDL_Rect src, dst;
const Uint8* keys = nullptr;
Uint8 just_pressed = SDL_SCANCODE_UNKNOWN;

Uint8 screen_map[16 * 12];
Uint8 screen_color[16 * 12];
//Uint8 char_map[256 * 8];
Uint8 screen_buffer[128 * 96 * 4];
static Uint8 cursor_x = 0;
static Uint8 cursor_y = 0;

static Uint8 color = 0x24;
static Uint8 border = 0x02;
static Uint8 data_stack[256];
static int data_stack_pos = 0;

static Uint8 palette[16][4] = {
	{ 255, 0, 0, 255 },
	{ 255, 0, 255, 0 },
	{ 255, 255, 0, 0 },
	{ 255, 255, 0, 255 },
	{ 255, 0, 255, 255 },
	{ 255, 255, 255, 0 },
	{ 255, 255, 255, 255 },
	{ 255, 0, 0, 0 },
	{ 255, 0, 0, 128 },
	{ 255, 0, 128, 0 },
	{ 255, 128, 0, 0 },
	{ 255, 128, 0, 128 },
	{ 255, 0, 128, 128 },
	{ 255, 128, 128, 0 },
	{ 255, 128, 128, 128 },
	{ 255, 0, 0, 0 },
};

void vdp_init() {
	SDL_Init(SDL_INIT_EVERYTHING);
	sdlWindow = SDL_CreateWindow("PaCo", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 608, 480, SDL_WINDOW_SHOWN);
	sdlRenderer = SDL_CreateRenderer(sdlWindow, -1, SDL_RENDERER_PRESENTVSYNC);
	//SDL_SetRenderDrawBlendMode(sdlRenderer, SDL_BLENDMODE_BLEND);
	SDL_RenderSetLogicalSize(sdlRenderer, 152, 120);

	//jtexture texture = (jtexture)malloc(sizeof(jtexture_t));
	//FILE* f = fopen("font.png", "rb");
	//if (!f) { error = 2; return; }
	//int c;
	//int size = 128;
	//Uint8* buffer = stbi_load_from_file(f, &size, &size, &c, 4);
	sdlTexture = SDL_CreateTexture(sdlRenderer, SDL_PIXELFORMAT_ABGR8888, SDL_TEXTUREACCESS_STATIC, 128, 128);
	//SDL_UpdateTexture(sdlTexture, NULL, buffer, 128 * sizeof(Uint32));
	//SDL_SetTextureBlendMode(sdlTexture, SDL_BLENDMODE_BLEND);
	//stbi_image_free(buffer);
	//fclose(f);

	src.x = src.y = 0;
	dst.x = dst.y = 12;
	src.w = dst.w = 128;
	src.h = dst.h = 96;
}

void vdp_quit() {
	SDL_DestroyTexture(sdlTexture);
	SDL_DestroyRenderer(sdlRenderer);
	SDL_DestroyWindow(sdlWindow);
	SDL_Quit();
}

static void flip() {
	Uint8* sb = screen_buffer;
	Uint8* sm = screen_map;
	Uint8* sc = screen_color;
	for (int y = 0; y < 12; y++) {
		for (int x = 0; x < 16; x++) {
			Uint8* cm = &char_map[*sm << 3];
			Uint8* sbt = sb;
			for (int l = 0; l < 8; l++) {
				if (*cm & 128) memcpy(sbt, palette[*sc & 0x0F], 4); else memcpy(sbt, palette[*sc >> 4], 4); sbt += 4;
				if (*cm &  64) memcpy(sbt, palette[*sc & 0x0F], 4); else memcpy(sbt, palette[*sc >> 4], 4); sbt += 4;
				if (*cm &  32) memcpy(sbt, palette[*sc & 0x0F], 4); else memcpy(sbt, palette[*sc >> 4], 4); sbt += 4;
				if (*cm &  16) memcpy(sbt, palette[*sc & 0x0F], 4); else memcpy(sbt, palette[*sc >> 4], 4); sbt += 4;
				if (*cm &   8) memcpy(sbt, palette[*sc & 0x0F], 4); else memcpy(sbt, palette[*sc >> 4], 4); sbt += 4;
				if (*cm &   4) memcpy(sbt, palette[*sc & 0x0F], 4); else memcpy(sbt, palette[*sc >> 4], 4); sbt += 4;
				if (*cm &   2) memcpy(sbt, palette[*sc & 0x0F], 4); else memcpy(sbt, palette[*sc >> 4], 4); sbt += 4;
				if (*cm &   1) memcpy(sbt, palette[*sc & 0x0F], 4); else memcpy(sbt, palette[*sc >> 4], 4); sbt += 512;
				cm++;
			}
			sm++; sc++; sb += 32;
		}
		sb += 3584;
	}
	SDL_UpdateTexture(sdlTexture, NULL, screen_buffer, 128 * sizeof(Uint32));
	SDL_RenderCopy(sdlRenderer, sdlTexture, &src, &dst);
	SDL_RenderPresent(sdlRenderer);
}

void vdp_data_out(const unsigned char& value) {
	data_stack[data_stack_pos++] = value;
}

void vdp_cmd_out(const unsigned char& value) {
	Uint8 n;
	switch (value) {
	case VDP_CMD_LOCATE:
		cursor_y = data_stack[--data_stack_pos]; cursor_x = data_stack[--data_stack_pos]; break;
	case VDP_CMD_PRINT:
		for (int i = 0; i < data_stack_pos; i++) {
			screen_map[cursor_x + (cursor_y << 7)] = data_stack[i];
			screen_color[cursor_x + (cursor_y << 7)] = color;
			cursor_x++; if (cursor_x == 16) { cursor_x = 0; cursor_y++; }
		}
		break;
	case VDP_CMD_PUTCHAR:
		cursor_x = data_stack[data_stack_pos - 4];
		cursor_y = data_stack[data_stack_pos - 3];
		screen_map[cursor_x + (cursor_y << 7)] = data_stack[data_stack_pos-2];
		screen_color[cursor_x + (cursor_y << 7)] = data_stack[data_stack_pos - 1];
		break;
	case VDP_CMD_SETCHAR:
		n = data_stack[data_stack_pos - 9];
		char_map[(n << 3)] = data_stack[data_stack_pos - 8];
		char_map[(n << 3) + 1] = data_stack[data_stack_pos - 7];
		char_map[(n << 3) + 2] = data_stack[data_stack_pos - 6];
		char_map[(n << 3) + 3] = data_stack[data_stack_pos - 5];
		char_map[(n << 3) + 4] = data_stack[data_stack_pos - 4];
		char_map[(n << 3) + 5] = data_stack[data_stack_pos - 3];
		char_map[(n << 3) + 6] = data_stack[data_stack_pos - 2];
		char_map[(n << 3) + 7] = data_stack[data_stack_pos - 1];
		break;
	case VDP_CMD_PUTSPRITE:
		break;
	case VDP_CMD_SETSPRITE:
		break;
	case VDP_CMD_FLIP:
		flip(); break;
	case VDP_CMD_COLOR:
		color = data_stack[0];
		break;
	case VDP_CMD_BORDER:
		border = data_stack[0];
		break;
	}
	data_stack_pos = 0;
}

unsigned char vdp_in() {
	return 0;
}

/*int main(int argc, char* argv[]) {
	static bool should_quit = false;
	static SDL_Event sdlEvent;

	while (!should_quit) {
		just_pressed = SDL_SCANCODE_UNKNOWN;
		while (SDL_PollEvent(&sdlEvent)) {
			if (sdlEvent.type == SDL_QUIT) { should_quit = true; break; }
			else if (sdlEvent.type == SDL_KEYDOWN) {
				//anyKey = true;
				just_pressed = sdlEvent.key.keysym.scancode;
				if (sdlEvent.key.keysym.scancode == SDL_SCANCODE_ESCAPE) { should_quit = true; }
			}
		}
		//if (!should_quit) should_quit = currentLoop();
	}

	vbm_quit();
	return 0;
}*/