package be.nikiroo.jvcard.parsers;

import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import be.nikiroo.jvcard.Card;
import be.nikiroo.jvcard.Contact;
import be.nikiroo.jvcard.Data;
import be.nikiroo.jvcard.TypeInfo;

public class Vcard21Parser {
	/**
	 * Load the given data from under the given {@link Format}.
	 * 
	 * @param lines
	 *            the input to load from
	 * @param format
	 *            the {@link Format} to load as
	 * 
	 * @return the list of elements
	 */
	public static List<Contact> parseContact(Iterable<String> textData) {
		Iterator<String> lines = textData.iterator();
		List<Contact> contacts = new LinkedList<Contact>();
		List<String> datas = null;

		String nextRawLine = null;
		if (lines.hasNext()) {
			nextRawLine = lines.next();
			while (lines.hasNext() && isContinuation(nextRawLine)) {
				// BAD INPUT FILE. IGNORE.
				System.err
						.println("VCARD Parser warning: CONTINUATION line seen before any data line");
				nextRawLine = lines.next();
			}
		}

		while (nextRawLine != null) {
			StringBuilder rawLine = new StringBuilder(nextRawLine.trim());
			if (lines.hasNext())
				nextRawLine = lines.next();
			else
				nextRawLine = null;

			while (isContinuation(nextRawLine)) {
				rawLine.append(nextRawLine.trim());
				if (lines.hasNext())
					nextRawLine = lines.next();
				else
					nextRawLine = null;
			}

			String line = rawLine.toString();
			if (line.equals("BEGIN:VCARD")) {
				datas = new LinkedList<String>();
			} else if (line.equals("END:VCARD")) {
				if (datas == null) {
					// BAD INPUT FILE. IGNORE.
					System.err
							.println("VCARD Parser warning: END:VCARD seen before any VCARD:BEGIN");
				} else {
					contacts.add(new Contact(parseData(datas)));
				}
			} else {
				if (datas == null) {
					// BAD INPUT FILE. IGNORE.
					System.err
							.println("VCARD Parser warning: data seen before any VCARD:BEGIN");
				} else {
					datas.add(line);
				}
			}
		}

		return contacts;
	}

	/**
	 * Load the given data from under the given {@link Format}.
	 * 
	 * @param lines
	 *            the input to load from
	 * @param format
	 *            the {@link Format} to load as
	 * 
	 * @return the list of elements
	 */
	public static List<Data> parseData(Iterable<String> textData) {
		List<Data> datas = new LinkedList<Data>();

		for (String line : textData) {
			List<TypeInfo> types = new LinkedList<TypeInfo>();
			String name = "";
			String value = "";
			String group = "";

			if (line.contains(":")) {
				int colIndex = line.indexOf(':');
				String rest = line.substring(0, colIndex);
				value = line.substring(colIndex + 1);

				if (rest.contains(";")) {
					String tab[] = rest.split(";");
					name = tab[0];

					for (int i = 1; i < tab.length; i++) {
						if (tab[i].contains("=")) {
							int equIndex = tab[i].indexOf('=');
							String tname = tab[i].substring(0, equIndex);
							String tvalue = tab[i].substring(equIndex + 1);
							types.add(new TypeInfo(tname, tvalue));
						} else {
							types.add(new TypeInfo(tab[i], ""));
						}
					}
				} else {
					name = rest;
				}
			} else {
				name = line;
			}

			if (name.contains(".")) {
				int dotIndex = name.indexOf('.');
				group = name.substring(0, dotIndex);
				name = name.substring(dotIndex + 1);
			}

			datas.add(new Data(types, name, value, group));
		}

		return datas;
	}

	/**
	 * Return a {@link String} representation of the given {@link Card}, line by
	 * line.
	 * 
	 * @param card
	 *            the card to convert
	 * 
	 * @return the {@link String} representation
	 */
	public static List<String> toStrings(Card card) {
		List<String> lines = new LinkedList<String>();

		for (Contact contact : card) {
			lines.addAll(toStrings(contact, -1));
		}

		return lines;
	}

	/**
	 * Return a {@link String} representation of the given {@link Contact}, line
	 * by line.
	 * 
	 * @param card
	 *            the contact to convert
	 * 
	 * @param startingBKey
	 *            the starting BKey number (all the other will follow) or -1 for
	 *            no BKey
	 * 
	 * @return the {@link String} representation
	 */
	public static List<String> toStrings(Contact contact, int startingBKey) {
		List<String> lines = new LinkedList<String>();

		lines.add("BEGIN:VCARD");
		lines.add("VERSION:2.1");
		for (Data data : contact) {
			lines.addAll(toStrings(data));
		}
		lines.add("END:VCARD");

		return lines;
	}

	/**
	 * Return a {@link String} representation of the given {@link Data}, line by
	 * line.
	 * 
	 * @param data
	 *            the data to convert
	 * 
	 * @return the {@link String} representation
	 */
	public static List<String> toStrings(Data data) {
		List<String> lines = new LinkedList<String>();

		StringBuilder dataBuilder = new StringBuilder();
		if (data.getGroup() != null && !data.getGroup().trim().equals("")) {
			dataBuilder.append(data.getGroup().trim());
			dataBuilder.append('.');
		}
		dataBuilder.append(data.getName());
		for (TypeInfo type : data) {
			dataBuilder.append(';');
			dataBuilder.append(type.getName());
			if (type.getValue() != null && !type.getValue().trim().equals("")) {
				dataBuilder.append('=');
				dataBuilder.append(type.getValue());
			}
		}
		dataBuilder.append(':');

		// TODO: bkey!
		dataBuilder.append(data.getValue());

		// RFC says: Content lines SHOULD be folded to a maximum width of 75
		// octets -> since it is SHOULD, we will just cut it as 74/75 chars
		// depending if the last one fits in one char (note: chars != octet)
		boolean continuation = false;
		while (dataBuilder.length() > 0) {
			int stop = 74;
			if (continuation)
				stop--; // the space takes 1
			if (dataBuilder.length() > stop) {
				char car = dataBuilder.charAt(stop - 1);
				// RFC forbids cutting a character in 2
				if (Character.isHighSurrogate(car)) {
					stop++;
				}
			}

			stop = Math.min(stop, dataBuilder.length());
			if (continuation) {
				lines.add(' ' + dataBuilder.substring(0, stop));
			} else {
				lines.add(dataBuilder.substring(0, stop));
			}
			dataBuilder.delete(0, stop);

			continuation = true;
		}

		return lines;
	}

	/**
	 * Clone the given {@link Card} by exporting then importing it again in VCF.
	 * 
	 * @param c
	 *            the {@link Card} to clone
	 * 
	 * @return the clone {@link Contact}
	 */
	public static Card clone(Card c) {
		return new Card(parseContact(toStrings(c)));
	}

	/**
	 * Clone the given {@link Contact} by exporting then importing it again in
	 * VCF.
	 * 
	 * @param c
	 *            the {@link Contact} to clone
	 * 
	 * @return the clone {@link Contact}
	 */
	public static Contact clone(Contact c) {
		return parseContact(toStrings(c, -1)).get(0);
	}

	/**
	 * Check if the given line is a continuation line or not.
	 * 
	 * @param line
	 *            the line to check
	 * 
	 * @return TRUE if the line is a continuation line
	 */
	private static boolean isContinuation(String line) {
		if (line != null && line.length() > 0)
			return (line.charAt(0) == ' ' || line.charAt(0) == '\t');
		return false;
	}
}