//This program is used to essentially download every Cyanide and Happiness comic
//By entering the first link of the comic's page, the program will save that image to your computer
//then go to the previous page and download that picture
//It will continue until you stop the program
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;
import java.net.URL;
import java.nio.channels.Channels;
import java.nio.channels.ReadableByteChannel;
import java.util.Scanner;


public class CHDownloader {

	
	public static void main(String[] args) throws IOException {
		System.out.println("About CHDownloader:");
		System.out.println("This program will essentially download every comic from Cyanide and Happiness");
		System.out.println("It will start at your link, then move to PREVIOUS pages");
		System.out.println("Enter the Cyanide and Happiness comic number to start with It's found in the URL. Ex 2776");
		Scanner userInput = new Scanner(System.in);
		int theURL = userInput.nextInt();
		//System.out.println("Your images will have the following names: chimage-0.jpg,chimage-1.jpg etc");
		//System.out.println("Please enter your starting number. 0 or 1 is recommended:");
		//int chLinkNumber = userInput.nextInt();
		System.out.println("Press Ctrl + C to stop the program");
		
		//int damnLOLLinkNumber = 0;//Used to name every image
		//String theURL = "http://www.damnlol.com/i-shall-call-him-18574.html";//The first page the program will start at. It will go to every PREVIOUS page.
		URL link = new URL("http://www.explosm.net/comics/"+theURL+"/");//Created the first URL using the link above

		while(1>0){
		
			//This section downloads the HTML page
		    ReadableByteChannel rbc = Channels.newChannel(link.openStream());//Gets the html page
		    FileOutputStream fos = new FileOutputStream("page.html");//Creates the output name of the html page to be saved to the computer
		    fos.getChannel().transferFrom(rbc, 0, 1 << 24);
		    Scanner sc = new Scanner(new FileReader("page.html"));//Takes the downloaded HTML page and sends it to a scanner

		    
		    
		    																		
		    
		    //This section converts the html page to the string
		    String contents = "";
			while(sc.hasNextLine() || sc.hasNext()){
				contents = contents + sc.nextLine() + "\n"; //Contents is the html page as a string!
			}
			sc.close();//Closes the scanner file
			
			
			//This finds the next url to scan!
			/*Scanner sc2 = new Scanner(contents);//Takes the string version of the html page and sends it to a new scanner
			int counter = 0;//The previous page's url is on line 8, so I use this int as a counter
			String nextURL = "";
			while((sc2.hasNext() || sc2.hasNextLine()) && (counter != 8)){
			nextURL = sc2.findWithinHorizon("[h][t][t][p][:][/][/][w][w][w][.][d][a][m][n][l][o][l][.][c][o][m][/].*[.][h][t][m][l]", 0);//This grabs the url and saves it to a string
			counter += 1;//Adds one to the counter so it will stop at 8
			}
			link = new URL(nextURL);//This now sets link as the newly found url so when the program starts back at the top it will now download this HTML page
			//Ends next url!*/
			
			
			//This section finds the image to download
			Scanner sc2 = new Scanner(contents);//Sends the html to a scanner
			String theImage = "";
			int counter2 = 0;//I think that the image url is on line 2 so I need a counter
			while((sc2.hasNext() || sc2.hasNextLine()) && (counter2 != 1)){
			//theImage = sc2.findWithinHorizon("[h][t][t][p][:][/][/]www.explosm.net/db/files/Comics/.*[jJpPgG][pPnNiI][eE]?[gGfF]", 0);//This finds the image's url and saves it to a string
			theImage = sc2.findWithinHorizon("[h][t][t][p][:][/][/]www.explosm.net/db/files/Comics/.*[.][jJpPgG][pPnNiI][eE]?[gGfF]", 0);//This finds the image's url and saves it to a string
			counter2 += 1;//Adds one to my counter
			System.out.println(theImage);
			}
			//Ends finding image

			
			
			
			//This section determines the file extension
				String imageType = "";
				if(theImage.matches(".*[.][jJ][pP][gG]")){
					imageType = ".jpg";
				}
				if(theImage.matches(".*[.][jJ][pP][eE][gG]")){
					imageType = ".jpeg";
				}
				if(theImage.matches(".*[.][pP][nN][gG]")){
					imageType = ".png";
				}
				if(theImage.matches(".*[.][gG][iI][Ff]")){
					imageType = ".gif";
				}
				
			
			
			
			//This section saves the image itself
			URL link2 = new URL(theImage);//A new URL is created with the image's url that was found
			String chLinkFinal = "CH-" + theURL + imageType;//The string that will be used to name the file
	
		    ReadableByteChannel rbc2 = Channels.newChannel(link2.openStream());//Gets the image
		    FileOutputStream fos2 = new FileOutputStream(chLinkFinal);//The output of the file name
		    fos2.getChannel().transferFrom(rbc2, 0, 1 << 24);
		    System.out.println("Image Saved: " + chLinkFinal);//Prints the name of the file that is saved
		    theURL -= 1;
		    link = new URL("www.explosm.net/comics/"+theURL);//Sets up the next page to be read
		
		}
	}

}