#include <SD.h>
#include <stdio.h>

#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

File dir;
int cs = 5;
bool state = true;
int cnt = 0;
int cnt2 = 0;

char img [7000];


#define OLED_RESET     -1
#define SCREEN_WIDTH		128
#define SCREEN_HEIGHT		64

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

void setup(){
	//reading textfile
	Serial.begin(115200);
	Serial.println("IfSD - Ver.1.00");
	Serial.println("# detecting SD-card ...");
	if (!SD.begin(cs)){
		Serial.println("  -> no SD-card detected");
		state = false;
	}
	if(state == true){
		Serial.println("  -> SD-card detected");
	}
	Serial.println("# listing card files ...");
	dir = SD.open("/");
	
	while (true){
		File entry =  dir.openNextFile();
		if (! entry) {
			Serial.println("  -> End of files");
			break;
		}
		Serial.print("  [");
		Serial.print(cnt);
		Serial.print("] ");
		Serial.println(entry.name());
		cnt++;
	}

	File textFile = SD.open("/file2choose.txt");

	char fileName[100] = "/";

	if (textFile) {
    Serial.print("# File choosen: ");
    while (textFile.available()) {
			sprintf(fileName,"%s%c",fileName,textFile.read());
    }
		Serial.println(fileName);
    textFile.close();
  } else {
    Serial.println("  -> an error occured reading 'file2choose.txt'");
  }
	Serial.println("# reading file content ...");
	//Serial.println("# File content:");
	File imageFile = SD.open(fileName);

	while(imageFile.available() && cnt2 < 7000){
		sprintf(img,"%s%c",img,imageFile.read());
		cnt2++;
	}
	imageFile.close();

	Serial.println("# reading complete");
	//Serial.println(img);
	

	//init display
	Serial.println("# initialize display ...");
	if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { 
    Serial.println("  -> no display detected");
    for(;;);
  }
	else{
		Serial.println("  -> display found");
		String s_img(img); 
		Serial.println(s_img);
		
		display.clearDisplay();

		static const unsigned char PROGMEM logo_bmp[7000] = {reinterpret_cast<const unsigned char*>(s_img).c_str()};

		display.drawBitmap(0, 0,logo_bmp, 128, 8, 1);
		
		display.display();
	}
}

void loop(){
}