package be.nikiroo.fanfix.supported;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.Map.Entry;
import java.util.Scanner;

import be.nikiroo.fanfix.Instance;
import be.nikiroo.fanfix.bundles.Config;

/**
 * Support class for local stories encoded in textual format, with a few rules:
 * <ul>
 * <li>The title must be on the first line</li>
 * <li>The author (preceded by nothing, "by " or "©") must be on the second
 * line, possibly with the publication date in parenthesis (i.e., "
 * <tt>By Unknown (3rd October 1998)</tt>")</li>
 * <li>Chapters must be declared with "<tt>Chapter x</tt>" or "
 * <tt>Chapter x: NAME OF THE CHAPTER</tt>", where "<tt>x</tt>" is the chapter
 * number</li>
 * <li>A description of the story must be given as chapter number 0</li>
 * <li>A cover may be present, with the same filename but a PNG, JPEG or JPG
 * extension</li<
 * </ul>
 * 
 * @author niki
 */
class Text extends BasicSupport {
	@Override
	protected boolean isHtml() {
		return false;
	}

	@Override
	public String getSourceName() {
		return "text";
	}

	@Override
	protected String getPublisher(URL source, InputStream in)
			throws IOException {
		return "";
	}

	@Override
	protected String getSubject(URL source, InputStream in) throws IOException {
		try {
			File file = new File(source.toURI());
			return file.getParentFile().getName();
		} catch (URISyntaxException e) {
			throw new IOException("Cannot parse the URL to File: "
					+ source.toString(), e);
		}

	}

	@Override
	protected String getLang(URL source, InputStream in) throws IOException {
		@SuppressWarnings("resource")
		Scanner scan = new Scanner(in, "UTF-8");
		scan.useDelimiter("\\n");
		scan.next(); // Title
		scan.next(); // Author (Date)
		String chapter0 = scan.next(); // empty or Chapter 0
		while (chapter0.isEmpty()) {
			chapter0 = scan.next();
		}

		String lang = detectChapter(chapter0);
		if (lang == null) {
			lang = super.getLang(source, in);
		} else {
			lang = lang.toUpperCase();
		}

		return lang;
	}

	@Override
	protected String getTitle(URL source, InputStream in) throws IOException {
		@SuppressWarnings("resource")
		Scanner scan = new Scanner(in, "UTF-8");
		scan.useDelimiter("\\n");
		return scan.next();
	}

	@Override
	protected String getAuthor(URL source, InputStream in) throws IOException {
		@SuppressWarnings("resource")
		Scanner scan = new Scanner(in, "UTF-8");
		scan.useDelimiter("\\n");
		scan.next();
		String authorDate = scan.next();

		String author = authorDate;
		int pos = authorDate.indexOf('(');
		if (pos >= 0) {
			author = authorDate.substring(0, pos);
		}

		return author;
	}

	@Override
	protected String getDate(URL source, InputStream in) throws IOException {
		@SuppressWarnings("resource")
		Scanner scan = new Scanner(in, "UTF-8");
		scan.useDelimiter("\\n");
		scan.next();
		String authorDate = scan.next();

		String date = "";
		int pos = authorDate.indexOf('(');
		if (pos >= 0) {
			date = authorDate.substring(pos + 1).trim();
			pos = date.lastIndexOf(')');
			if (pos >= 0) {
				date = date.substring(0, pos).trim();
			}
		}

		return date;
	}

	@Override
	protected String getDesc(URL source, InputStream in) {
		return getChapterContent(source, in, 0);
	}

	@Override
	protected URL getCover(URL source, InputStream in) {
		String path;
		try {
			path = new File(source.toURI()).getPath();
		} catch (URISyntaxException e) {
			Instance.syserr(e);
			path = null;
		}

		for (String ext : new String[] { ".txt", ".text", ".story" }) {
			if (path.endsWith(ext)) {
				path = path.substring(0, path.length() - ext.length());
			}
		}

		return getImage(source, path);
	}

	@Override
	protected List<Entry<String, URL>> getChapters(URL source, InputStream in) {
		List<Entry<String, URL>> chaps = new ArrayList<Entry<String, URL>>();
		@SuppressWarnings("resource")
		Scanner scan = new Scanner(in, "UTF-8");
		scan.useDelimiter("\\n");
		boolean descSkipped = false;
		boolean prevLineEmpty = false;
		while (scan.hasNext()) {
			String line = scan.next();
			if (prevLineEmpty && detectChapter(line) != null) {
				if (descSkipped) {
					String chapName = Integer.toString(chaps.size());
					int pos = line.indexOf(':');
					if (pos >= 0 && pos + 1 < line.length()) {
						chapName = line.substring(pos + 1).trim();
					}
					final URL value = source;
					final String key = chapName;
					chaps.add(new Entry<String, URL>() {
						public URL setValue(URL value) {
							return null;
						}

						public URL getValue() {
							return value;
						}

						public String getKey() {
							return key;
						}
					});
				} else {
					descSkipped = true;
				}
			}

			prevLineEmpty = line.trim().isEmpty();
		}

		return chaps;
	}

	@Override
	protected String getChapterContent(URL source, InputStream in, int number) {
		StringBuilder builder = new StringBuilder();
		@SuppressWarnings("resource")
		Scanner scan = new Scanner(in, "UTF-8");
		scan.useDelimiter("\\n");
		boolean inChap = false;
		boolean prevLineEmpty = false;
		while (scan.hasNext()) {
			String line = scan.next();
			if (prevLineEmpty) {
				if (detectChapter(line, number) != null) {
					inChap = true;
				} else if (inChap) {
					if (prevLineEmpty && detectChapter(line) != null) {
						break;
					}

					builder.append(line);
					builder.append("\n");
				}
			}

			prevLineEmpty = line.trim().isEmpty();
		}

		return builder.toString();
	}

	@Override
	protected boolean supports(URL url) {
		if ("file".equals(url.getProtocol())) {
			File file;
			try {
				file = new File(url.toURI());
				file = new File(file.getPath() + ".info");
			} catch (URISyntaxException e) {
				Instance.syserr(e);
				file = null;
			}

			return file == null || !file.exists();
		}

		return false;
	}

	/**
	 * Check if the given line looks like a starting chapter in a supported
	 * language, and return the language if it does (or NULL if not).
	 * 
	 * @param line
	 *            the line to check
	 * 
	 * @return the language or NULL
	 */
	private String detectChapter(String line) {
		return detectChapter(line, null);
	}

	/**
	 * Check if the given line looks like the given starting chapter in a
	 * supported language, and return the language if it does (or NULL if not).
	 * 
	 * @param line
	 *            the line to check
	 * 
	 * @return the language or NULL
	 */
	private String detectChapter(String line, Integer number) {
		line = line.toUpperCase();
		for (String lang : Instance.getConfig().getString(Config.CHAPTER)
				.split(",")) {
			String chapter = Instance.getConfig().getStringX(Config.CHAPTER,
					lang);
			if (chapter != null && !chapter.isEmpty()) {
				chapter = chapter.toUpperCase() + " ";
				if (line.startsWith(chapter)) {
					if (number != null) {
						// We want "[CHAPTER] [number]: [name]", with ": [name]"
						// optional
						String test = line.substring(chapter.length()).trim();
						if (test.startsWith(Integer.toString(number))) {
							test = test.substring(
									Integer.toString(number).length()).trim();
							if (test.isEmpty() || test.startsWith(":")) {
								return lang;
							}
						}
					} else {
						return lang;
					}
				}
			}
		}

		return null;
	}
}