// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
//
//
//
//  Contents:  Text run Typography properties
//
//  Spec:      Text Formatting API.doc
//
//
 
 
using MS.Internal.Text.TextInterface;
 
namespace System.Windows.Media.TextFormatting
{
    /// <summary>
    /// Text run typography properties
    ///
    /// Client set properties to generate set of features 
    /// that will be processed by OpenType layout engine.
    ///
    /// For details see OpenType font specification at
    ///      https://docs.microsoft.com/typography/
    ///
    /// </summary>
    public abstract class TextRunTypographyProperties
    {
        #region Public typography properties   
        
        /// <summary>
        /// Common ligatures assisting with text readability.
        /// Examples: fi, fl ligatures
        /// </summary>
        public abstract bool StandardLigatures
        { get; }
        
        /// <summary>
        /// Ligature forms depending on surrounding context
        /// </summary>
        public abstract bool ContextualLigatures
        { get; }
 
        /// <summary>
        /// Additional ligatures to assist with text readability
        /// Examples: Qu, Th
        /// </summary>
        public abstract bool DiscretionaryLigatures 
        { get; }
        
        /// <summary>
        /// Ligatures used in historical typography
        /// Examples: ct, st
        /// </summary>
        public abstract bool HistoricalLigatures
        { get; }
 
        /// <summary>
        /// Custom forms defined by surrounding context
        /// Examples: multiple medial forms in Urdu Nastaliq fonts
        /// </summary>
        public abstract bool ContextualAlternates
        { get; }
 
        /// <summary>
        /// Forms commonly used in the past
        /// Examples: long s, old Fraktur k
        /// </summary>
        public abstract bool HistoricalForms 
        { get; }
 
        /// <summary>
        /// Feature adjusting spacing between charactersto enchance word shape
        /// </summary>
        public abstract bool Kerning
        { get; }
 
        /// <summary>
        /// Feature adjusting inter-glyph spacing to provide better readability for all-`capital text
        /// </summary>
        public abstract bool CapitalSpacing 
        { get; }
 
        /// <summary>
        /// Feature adjusting punctuation types of characters to the case of the surrounding glyphs
        /// </summary>
        public abstract bool CaseSensitiveForms 
        { get; }
 
        /// <summary>
        /// Font specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet1
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet2
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet3
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet4 
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet5 
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet6 
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet7 
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet8
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet9 
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet10
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet11
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet12 
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet13 
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet14 
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet15
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet16 
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet17
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet18 
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet19
        { get; }
 
        /// <summary>
        /// Font-specific set of glyph forms designed to work with each other.
        /// </summary>
        public abstract bool StylisticSet20
        { get; }
 
        /// <summary>
        /// Substitute nominal zero with slashed zero.
        /// </summary>
        public abstract bool SlashedZero 
        { get; } 
 
        /// <summary>
        /// Substitute regular greek forms with forms used in mathematical notation.
        /// </summary>
        public abstract bool MathematicalGreek
        { get; } 
 
        /// <summary>
        /// Replace standard forms in Japaneese fonts with preferred typographic forms
        /// </summary>
        public abstract bool EastAsianExpertForms 
        { get; } 
 
        /// <summary>
        /// Render different types of typographic variations. Include Normal, Subscript, Superscript, 
        /// Inferior, Ordinal and Ruby.
        /// </summary>
        public abstract FontVariants Variants 
        { get; }
 
        /// <summary>
        /// Select set of `capital forms from Normal, SmallCaps, AllSmallCaps, 
        /// PetiteCaps, AllPetiteCaps, Unicase and Titling.
        /// </summary>
        public abstract FontCapitals Capitals 
        { get; }
 
        /// <summary>
        /// Feature selecting special fractional forms of nominator, denominator and slash. 
        /// </summary>
        public abstract FontFraction Fraction { get; }
 
        /// <summary>
        /// Select set of glyphs to render alternate numeral forms from Normal, OldStyle and Lining
        /// </summary>
        public abstract FontNumeralStyle NumeralStyle
        { get; } 
 
        /// <summary>
        /// Select glyph set for different numeral aligning options from Default, Proportional and Tabular
        /// </summary>
        public abstract FontNumeralAlignment NumeralAlignment 
        { get; }
 
        /// <summary>
        /// Select from different width styles for Latin characters in East Asian fonts.
        /// </summary>
        public abstract FontEastAsianWidths EastAsianWidths
        { get; } 
 
        /// <summary>
        /// Select glyphs forms specific for particular writing system and language.
        /// </summary>
        public abstract FontEastAsianLanguage EastAsianLanguage 
        { get; } 
        
        /// <summary>
        /// Select glyph forms having swashes by specified index.
        /// Examples: Q with tail extended under following letter
        /// </summary>
        public abstract int StandardSwashes
        { get; }
 
        /// <summary>
        /// Select swash forms of glyphs by specified index and based on surrounding characters.
        /// Examples: d with flourish occupying space above following ea.
        /// </summary>
        public abstract int ContextualSwashes 
        { get; } 
 
        /// <summary>
        /// Select alternate form of glyphs by specified index.
        /// Examples: multiple forms of ampersand.
        /// </summary>
        public abstract int StylisticAlternates 
        { get; }
 
        /// <summary>
        /// Forms commonly used in notation.
        /// Examples: characters placed in circles, parentheses
        /// </summary>
        public abstract int AnnotationAlternates 
        { get; }
        
        #endregion Public typography properties
        
        /// <summary>
        /// Should be called every time any property changes it's value
        /// </summary>
        protected void OnPropertiesChanged()
        {
            _features = null;
        }
        
        /// <summary>
        /// cached feature array.
        /// </summary>
        internal DWriteFontFeature[] CachedFeatureSet
        {
            get
            {
                return _features;
            }
            set
            {
                _features = value;
            }
        }
 
        private DWriteFontFeature[] _features = null;
}
}