/**
 * Write a description of class Library here.
 * 
 * @author (your name) 
 * @version (a version number or a date)
 */

// Import all required libraries. Not using .* as it is not good practice due to potential conflicts.
import java.util.ArrayList;
import java.util.Scanner;
import java.io.File;
import java.io.IOException;
import java.awt.FileDialog;
import java.awt.Frame;

public class Library
{
    private ArrayList<LibraryItem> itemList; // Initialise an ArrayList of name itemList to store LibraryItems
    
    /*
     * Constructor for objects of class Library
     */
    public Library()
    {
        itemList = new ArrayList<LibraryItem>();
    }
    
    /*
     * Appends a LibraryItem to the itemList.
     */
    public void storeItem( LibraryItem item )
    {
        itemList.add( item );
    }
    
    /*
     * Prints to the terminal all items in the itemList
     */
    public void printAllItems()
    {
        for( LibraryItem item : itemList )
        {
            item.printDetails();
        }
    }
    
    public void readItemData() //throws IOException
    {
        Frame frame = null; // Initialise a null frame
        FileDialog fileBox = new FileDialog( frame, "Open", FileDialog.LOAD ); // Initialise filebox with the null frame pointer
        fileBox.setVisible( true ); // Open a file selection dialog to the user.
        
        try {
            Scanner fileScanner = new Scanner( new File( fileBox.getDirectory() + fileBox.getFile() ) );
            String typeFlag = "";
            
            while( fileScanner.hasNextLine() ){
                
                String lineItem = fileScanner.nextLine();
                //System.out.println( lineItem );
                
                // Ensure no comments or empty lines are included
                if ( lineItem.contains( "//" ) || lineItem.trim().isEmpty() ){}
                
                // Check current line is a candidate flag
                else if ( lineItem.startsWith("[" ) ) {
                    if ( lineItem.toLowerCase().contains("book") ) {
                        typeFlag = "book";
                        //System.out.println( "CHANGED FLAG TO READ BOOKS" );
                    }
                    else if ( lineItem.toLowerCase().contains("periodical") ) {
                        typeFlag = "periodical";
                        //System.out.println( "CHANGED FLAG TO READ PERIODICALS" );
                    }  
                    else {
                        System.out.println( "Flag detected, but no accepted format...\n Cannot store item in Library. Changing Flag to generic and skipping the following: ");
                        typeFlag = "generic";
                    }
                }
                
                // Could be a switch case to be more efficient
                // Check current flag for data processing.
                else {
                    if ( typeFlag.equals( "book" ) ) {
                        // Process Book Data
                        Scanner detailScanner = new Scanner ( lineItem ).useDelimiter(","); // Create a new scanner to grab the values in a comma separated list
                        LibraryItem book = new Book();
                        book.readItemData( detailScanner );
                        storeItem( book ); // Store the new LibraryItem in the itemList
                    }
                    else if ( typeFlag.equals( "periodical" ) ) {
                        // Process Periodic Data
                        Scanner detailScanner = new Scanner ( lineItem ).useDelimiter(",");
                        LibraryItem periodical = new Periodical();
                        periodical.readItemData( detailScanner );
                        storeItem( periodical );
                    }
                    else if ( typeFlag.equals( "generic" ) ) {
                        // Output unaccepted lines
                        System.out.println( lineItem );
                    }
                }
            }
        }
        catch( IOException e ) { // Catch any IO Exceptions that may occur from improper file selection.
            System.err.println( "Caught IOException: " + e.getMessage() + "\nAn I/O Exception has occurred, please check file is readable and correct format." );
        }
    }
}