#include <3ds.h>
#include <stdio.h>
#include <cstdio>
#include <unistd.h>

//Filenames
#define EMUNAND_BIN "arm9loaderhax_emunand.bin"
#define SYSNAND_BIN "arm9loaderhax_sysnand.bin"
#define PAYLOAD_BIN "arm9loaderhax.bin"

//Options
#define	USERINPUT true

bool choice(const char* msg, const char* ch1, const char* ch2) {
	printf(msg);
	printf(ch1);
	printf(ch2);
	
	while(aptMainLoop()) {
		gspWaitForVBlank();
		hidScanInput();
        
		if(hidKeysDown() & KEY_A) {
			return true;
		}
		
		if(hidKeysDown() & KEY_B) {
			return false;
		}
            
		gfxFlushBuffers();
		gfxSwapBuffers();
	}
}

bool fileExists(const char* path) {
	if( access( path, F_OK ) != -1 ) {
		return true;
	} else {
		return false;
	}
}

void changetoEmunand() {
	printf("Changing to emunand...\n");
	
	//TODO: Prompt user for conflict
	if(fileExists(SYSNAND_BIN)) {
		if(choice("Already existing sysnand bin! Remove?\n", "A: Yes\n", "B: No\n")) {
			remove(SYSNAND_BIN);
			printf("Removed existing sysnand bin...\n");
		} else {
			printf("Cancelling...\n");
			return;
		}
	}
	
	//Rename files
	bool a = rename(PAYLOAD_BIN, SYSNAND_BIN);
	if(!a) {
		printf("Error while renaming file!\n");
	}
	
	rename(EMUNAND_BIN, PAYLOAD_BIN);
	
	//Die
	printf("Successfully changed payload to emunand!");
}

void changetoSysnand() {
	printf("Changing to sysnand...\n");
		
	//TODO: Prompt user for conflict
	if(fileExists(EMUNAND_BIN)) {
		if(choice("Already existing emunand bin! Remove?\n", "A: Yes\n", "B: No\n")) {
			remove(EMUNAND_BIN);
			printf("Removed existing emunand bin...\n");
		} else {
			printf("Cancelling...\n");
			return;
		}
	}
	
	//Rename files
	bool a = rename(PAYLOAD_BIN, EMUNAND_BIN);
	if(!a) {
		printf("Error while renaming file!\n");
	}
	rename(SYSNAND_BIN, PAYLOAD_BIN);
	
	//Die
	printf("Successfully changed payload to sysnand!");
}

void scan() {
	//Checks if this exists at all
	if(fileExists(PAYLOAD_BIN)) {
		printf("Found arm9loaderhax.bin\n");
		
		//Change to emunand
		if(fileExists(EMUNAND_BIN)) {
			printf("Found emunand bin!\n");
			changetoEmunand();
		} else {
			//Change to sysnand
			if(fileExists(SYSNAND_BIN)) {
				printf("Found sysnand bin!\n");
				changetoSysnand();
			}
		}
	} else {
		//If both files exist, default to sysnand
		if(fileExists(EMUNAND_BIN) && fileExists(SYSNAND_BIN)) {
			printf("Changing to sysnand...\n");
				
			//Rename files
			rename(SYSNAND_BIN, PAYLOAD_BIN);
				
			//Die
			printf("Successfully changed payload to sysnand!");
		} else {
			//Redundant?
			if(fileExists(SYSNAND_BIN)) {
				changetoSysnand();
			} else {
				//Try emunand bin
				if(fileExists(EMUNAND_BIN)) {
					changetoEmunand();
				} else {
					//Die
				}
			}
		}
	}
}

int main(int argc, char **argv) {
    gfxInitDefault();
    consoleInit(GFX_BOTTOM, NULL);
    
	printf("Checking for files on SD card...\n");
	
    scan();
    
	if(USERINPUT) {
		printf("Press START to exit.");
		
		while(aptMainLoop()) {
			gspWaitForVBlank();
			hidScanInput();
        
			if(hidKeysDown() & KEY_START)
				break;
            
			gfxFlushBuffers();
			gfxSwapBuffers();
		}
	}
    
    gfxExit();
    return 0;
}