SolLewitt.Grammar for Irony Parser

SolLewitt.Grammar

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Irony.Parsing;

namespace SolLewitt.Parser
{
    [Language("SolLewittDrawing", "0.1", "Sol Lewitt style drawing description language")]
    public class SolLewittGrammar : Grammar
    {
        public SolLewittGrammar() : base (false)
        {
            // 1. Terminals
            var upper = ToTerm("upper");
            var top = ToTerm("top");
            var lower = ToTerm("lower");
            var bottom = ToTerm("bottom");
            var left = ToTerm("left");
            var right = ToTerm("right");
            var center = ToTerm("center of the wall");
            var from = ToTerm("from");
            var to = ToTerm("to");
            var and = ToTerm("and");
            var start = ToTerm("start");
            var of = ToTerm("of");
            var end = ToTerm("end");
            var the = ToTerm("the");
            var halfwayBetween = ToTerm("halfway between");
            var midpointOf = ToTerm("midpoint of");
            var aPoint = ToTerm("a point");
            var comma = ToTerm(",");
            var dot = ToTerm(".");


            // 2. Non-terminals
            var LineDefinition = new NonTerminal("LineDefinition");
            var LineDefinitionList = new NonTerminal("LineDefinitionList");
            var PolygonDescription = new NonTerminal("PolygonDescription");
            var Polygon = new NonTerminal("Polygon");
            var Nth = new NonTerminal("Nth");
            var TopDirection = new NonTerminal("TopDirection");
            var BottomDirection = new NonTerminal("BottomDirection");
            var HorizontalDirection = new NonTerminal("HorizontalDirection");
            var VerticalDirection = new NonTerminal("VerticalDirection");
            var Direction = new NonTerminal("Direction");
            var PointList = new NonTerminal("PointList");
            var EquidistantPoint = new NonTerminal("EquidistantPoint");
            var CrossingLinesPoint = new NonTerminal("CrossingLinesPoint");
            var TwoPointsLine = new NonTerminal("TwoPointsLine");
            var Line = new NonTerminal("Line");
            var ReferencedLine = new NonTerminal("ReferencedLine");
            var Side = new NonTerminal("Side");
            var HalfwayPoint = new NonTerminal("HalfwayPoint");
            var Point = new NonTerminal("Point");
            var Corner = new NonTerminal("Corner");
            var Drawing = new NonTerminal("Drawing");
            var LineExtremityPoint = new NonTerminal("LineExtremityPoint");

            // 3. BNF rules
            TopDirection.Rule = (top | upper);
            BottomDirection.Rule = (bottom | lower);
            HorizontalDirection.Rule = (left | right);
            VerticalDirection.Rule = (TopDirection | BottomDirection);
            Direction.Rule = HorizontalDirection | VerticalDirection;

            Side.Rule = Direction + "side";

            TwoPointsLine.Rule = (from + Point + to + Point)
                | (Point + and + Point)
                | (Point + to + Point)
                | ("a line drawn" + TwoPointsLine) 
                | ("an axis between" + TwoPointsLine);

            Nth.Rule = ToTerm("first") | "second" | "third" | "fourth";

            ReferencedLine.Rule = Nth + "line";

            LineExtremityPoint.Rule = (start | end) + of + Line;

            Line.Rule = Side 
                | ReferencedLine
                | TwoPointsLine
                | the + Line
                | Line;

            HalfwayPoint.Rule =  halfwayBetween + Line
                | midpointOf + Line
                | aPoint + HalfwayPoint;

            CrossingLinesPoint.Rule = 
                aPoint + ToTerm("which is on") + Line + "where" + Line + "would cross that axis"
                | aPoint + "where a line would cross" + Line + "if it were drawn" + Line;

            PointList.Rule = MakeListRule(PointList, comma | and, Point);

            EquidistantPoint.Rule = aPoint + "equidistant from" + PointList;

            Point.Rule = HalfwayPoint 
                | Corner 
                | LineExtremityPoint
                | CrossingLinesPoint
                | EquidistantPoint
                | center
                | the + Point;

            Corner.Rule = VerticalDirection + HorizontalDirection + "corner";

            PolygonDescription.Rule = ToTerm("a") + "quadrangle" + "which is formed and enclosed by" + "four" + "lines";

            LineDefinition.Rule = the + Nth + (ToTerm("line") | "of which is drawn") + Line;

            LineDefinitionList.Rule = MakeListRule(LineDefinitionList, comma, LineDefinition);

            Polygon.Rule = PolygonDescription + comma + LineDefinitionList + dot;

            Drawing.Rule = MakeStarRule(Drawing, Polygon);

            this.Root = Drawing;

            // 4. Operators precedence

            // 5. Punctuation and transient terms
            MarkPunctuation(from, to, halfwayBetween, midpointOf, the, aPoint, and);
            MarkTransient(HorizontalDirection, VerticalDirection, Point, Line);

            this.LanguageFlags = LanguageFlags.NewLineBeforeEOF; 
        }
    }
}