package net.knarcraft.ffmpegconverter.streams;

/**
 * An object representation of a subtitle stream in a media file
 */
public class SubtitleStream extends AbstractStream implements StreamObject {
    final private String title;
    final private String file;
    final private boolean isFullSubtitle;
    final private boolean isImageSubtitle;

    /**
     * Instantiates a new subtitle stream
     *
     * @param codecName     <p>The name of the codec for the subtitle stream.</p>
     * @param absoluteIndex <p>The index of the subtitle stream.</p>
     * @param relativeIndex <p>The index of the subtitle stream relative to other subtitle streams.</p>
     * @param language      <p>The language of the subtitle stream.</p>
     * @param title         <p>The title of the subtitle stream.</p>
     * @param file          <p>The file containing the subtitle.</p>
     */
    public SubtitleStream(String codecName, int absoluteIndex, int relativeIndex, String language, String title,
                          String file) {
        this.codecName = codecName;
        this.absoluteIndex = absoluteIndex;
        this.language = language;
        this.title = title;
        this.isFullSubtitle = isFullSubtitle();
        this.relativeIndex = relativeIndex;
        this.isImageSubtitle = isImageSubtitle();
        this.file = file;
    }

    /**
     * Gets the title of the subtitle stream
     *
     * @return <p>The title of the subtitle stream.</p>
     */
    public String getTitle() {
        return this.title;
    }

    /**
     * Gets the file name of the file containing this subtitle
     *
     * @return <p>The file name containing the subtitle stream.</p>
     */
    public String getFile() {
        return this.file;
    }

    /**
     * Gets whether the subtitle is an image subtitle
     *
     * @return <p>Whether the subtitles is an image subtitle.</p>
     */
    public boolean getIsImageSubtitle() {
        return this.isImageSubtitle;
    }

    /**
     * Gets whether the subtitle is a full subtitle
     *
     * @return <p>Whether the subtitle is a full subtitle.</p>
     */
    public boolean getIsFullSubtitle() {
        return this.isFullSubtitle;
    }

    /**
     * Checks whether a subtitle is image based (as opposed to text based)
     *
     * @return <p>True if the subtitle is image based.</p>
     */
    private boolean isImageSubtitle() {
        return codecName != null && (getCodecName().equals("hdmv_pgs_subtitle")
                || getCodecName().equals("dvd_subtitle"));
    }

    /**
     * Checks whether the subtitle translates everything (as opposed to just songs and signs)
     *
     * @return <p>True if the subtitle translates everything.</p>
     */
    private boolean isFullSubtitle() {
        if (getTitle() == null) {
            return false;
        }
        String titleLowercase = getTitle().toLowerCase();
        return !titleLowercase.matches(".*signs?[ &/a-z]+songs?.*") &&
                !titleLowercase.matches(".*songs?[ &/a-z]+signs?.*") &&
                !titleLowercase.matches(".*forced.*");
    }
}