Quran Tajweed rules highlighter

بسم الله الرحمن الرحيم In the name of Allah, Most Gracious, Most Merciful

This is an example project that shows how to implement Quran Tajweed rules in flutter.
You can extract highlighting logic from it and use in your projects. Following rules are implemented:

• Ghunna
• Ikhfaa - Noon sakin and tanweens
• Ikhfaa - Meem sakin
• Idgham with ghunna - Noon sakin and tanweens
• Idgham with ghunna - Meem sakin
• Idgham without ghunna - Noon sakin and tanweens
• Idgham without ghunna - Shamsiyya
• Idgham without ghunna - Misleyn
• Idgham without ghunna - Mutajaniseyn
• Idgham without ghunna - Mutagaribeyn
• Iqlab - Noon sakin and tanweens
• Izhar - Noon sakin and tanweens
• Qalqala
• Prolonging - by 2, 4, 6
• Prolonging - Lin
• Prolonging - Ivad
• Prolonging - Muttasil
• Prolonging - Munfasil
• Prolonging - Lazim
• Alef tafreeq
• Hamzatul wasl

Getting Started

Main class that does tokenization is called Tajweed.
You call it like this: Tajweed.tokenize(String AyaText, int sura, int aya) and it returns List<TajweedToken> that you can later pass to RichText widget for displaying:

Text.rich(
    TextSpan(
        children: <TextSpan>[
        for (final token in tokens)
            TextSpan(
            text: token.text,
            style: TextStyle(
                fontFamily: 'Kitab',
                fontWeight: FontWeight.w400,
                fontSize: 30,
                color: token.rule.color(context) ??
                    Theme.of(context).colorScheme.onSurface,
            ),
            ),
        TextSpan(
            text: '\u06DD${(index + 1).toArabicDigits()}',
            style: TextStyle(
            fontFamily: 'Kitab',
            fontWeight: FontWeight.w400,
            fontSize: 30,
            color: Theme.of(context).colorScheme.onSurface,
            ),
        )
        ],
    ),
)

TajweedToken contains properties to indicate what rule and subrule were matched, so that you can for example display documentation of rule.

If you need to get tokens grouped by words (for example for highlighting in UI etc) you can call Tajweed.tokenizeAsWords(String AyaText, int sura, int aya) method and it will return List<TajweedWord> where every TajweedWord is one word that contains TajweedTokens inside it.

For performance use some cache variable in application and do not re-tokenize on every build method call.

Using pre-cached tokens

Project also contains a file called cached_tajweed_tokens.dart that contains a class called CachedTajweedTokens with a static field suraTokens. That field is a zero-indexed list of pre-cached tokens for all Suras and all Ayas. That file is quite large in size, but if you decide to use it, below is how.

//To retrieve tokens for last (7th) Aya of Sura Al Fatiha
final ayaTokens = CachedTajweedTokens.suraTokens[0][6]; //0 - Al Fatiha, 6 - Aya number 7

//To retrieve tokens word-by-word in List<TajweedWord>
final ayaTokens = CachedTajweedTokens.suraTokens[0][6];
final wordByWordTokens = Tajweed.tokensToWords(ayaTokens); //this operation is fast