// The `GDEF` table contains various glyph properties
// https://docs.microsoft.com/en-us/typography/opentype/spec/gdef

import check from '../check';
import { Parser } from '../parse';

var attachList = function() {
    return {
        coverage: this.parsePointer(Parser.coverage),
        attachPoints: this.parseList(Parser.pointer(Parser.uShortList))
    };
};

var caretValue = function() {
    var format = this.parseUShort();
    check.argument(format === 1 || format === 2 || format === 3,
        'Unsupported CaretValue table version.');
    if (format === 1) {
        return { coordinate: this.parseShort() };
    } else if (format === 2) {
        return { pointindex: this.parseShort() };
    } else if (format === 3) {
        // Device / Variation Index tables unsupported
        return { coordinate: this.parseShort() };
    }
};

var ligGlyph = function() {
    return this.parseList(Parser.pointer(caretValue));
};

var ligCaretList = function() {
    return {
        coverage: this.parsePointer(Parser.coverage),
        ligGlyphs: this.parseList(Parser.pointer(ligGlyph))
    };
};

var markGlyphSets = function() {
    this.parseUShort(); // Version
    return this.parseList(Parser.pointer(Parser.coverage));
};

function parseGDEFTable(data, start) {
    start = start || 0;
    const p = new Parser(data, start);
    const tableVersion = p.parseVersion(1);
    check.argument(tableVersion === 1 || tableVersion === 1.2 || tableVersion === 1.3,
        'Unsupported GDEF table version.');
    var gdef = {
        version: tableVersion,
        classDef: p.parsePointer(Parser.classDef),
        attachList: p.parsePointer(attachList),
        ligCaretList: p.parsePointer(ligCaretList),
        markAttachClassDef: p.parsePointer(Parser.classDef)
    };
    if (tableVersion >= 1.2) {
        gdef.markGlyphSets = p.parsePointer(markGlyphSets);
    }
    return gdef;
}
export default { parse: parseGDEFTable };