#include "output.h"

#include <string>
#include <cstring>
#include <cmath>
#include <cstdarg>
#include <cstdio>

#include <3ds.h>

#include "text.h"

static std::string bufferTop;
static std::string bufferBottom;
static int cnt;

static int countLines(const std::string& str)
{
	if (str.empty())
		return 0;

	int cnt = 1;
    for (const char& c : str) {
        if (c == '\n') cnt++;
    }
    
	return cnt;
}

static void deleteFirstLine(std::string* str)
{
	if (str->empty())
		return;
    
    size_t linebreak = str->find_first_of('\n');
    
    if (linebreak == std::string::npos || linebreak + 1 > str->length()) {
        *str = {};
        return;
    }
    
    *str = str->substr(linebreak + 1);
}

static void drawFrame(gfxScreen_t screen, char b, char g, char r)
{
	int screenWidth;
	std::string textBuffer;
	if (screen == GFX_TOP) {
		screenWidth = 400;
		textBuffer = bufferTop;
	} else {
		screenWidth = 320;
		textBuffer = bufferBottom;
	}

	u8* bufAdr = gfxGetFramebuffer(screen, GFX_LEFT, NULL, NULL);
	int x, y;
	for (x = 1; x < screenWidth; x++) {
		for (y = 1; y < 240; y++) {
			u32 v=(y + x * 240) * 3;
			bufAdr[v]   = b;
			bufAdr[v+1] = g;
			bufAdr[v+2] = r;
		}
	}

	x = countLines(textBuffer);
	while (x > (240 / fontDefault.height - 3)) {
		deleteFirstLine(&textBuffer);
		x--;
	}
	gfxDrawText(screen, GFX_LEFT, NULL, textBuffer.c_str(), 240 - fontDefault.height * 3, 10);
	cnt++;
}

void drawFrames()
{
	drawFrame(GFX_TOP, 0x88, 0x66, 0x00);
	drawFrame(GFX_BOTTOM, 0x00, 0x00, 0x00);
	gfxFlushBuffers();
	gfxSwapBuffers();
}

void print(gfxScreen_t screen, const char* format, ...)
{
	std::string& textBuffer = (screen == GFX_TOP) ? bufferTop : bufferBottom;
	va_list arguments;
	char newStr[512];

	va_start(arguments, format);
	vsprintf(newStr, format, arguments);
	va_end(arguments);

	textBuffer += newStr;
	svcOutputDebugString(newStr, strlen(newStr));

	drawFrames();
}

void clearScreen(gfxScreen_t screen)
{
	bufferTop[0] = 0;
	drawFrames();
}

void clearScreens()
{
	clearScreen(GFX_TOP);
	clearScreen(GFX_BOTTOM);
}