package io.trygvis.ld;

import io.trygvis.ld.antlr.GnuLdParser;
import io.trygvis.ld.antlr.GnuLdParserBaseListener;
import org.antlr.v4.runtime.tree.ParseTreeProperty;

import java.math.BigInteger;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

class ElfinfoGnuLdListener extends GnuLdParserBaseListener {
    public List<LdLoader.MemoryArea> memoryAreas = new ArrayList<>();

    private final ParseTreeProperty<BigInteger> expr = new ParseTreeProperty<>();

    @Override
    public void exitExpInt(GnuLdParser.ExpIntContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.exitExpInt: ctx.INT().getText() = " + ctx.INT().getText());
        expr.put(ctx, ElfinfoExprVisitor.parseInt(ctx.INT().getText()));
    }

    @Override
    public void exitExpSub(GnuLdParser.ExpSubContext ctx) {
        BigInteger a = expr.get(ctx.exp(0));
        BigInteger b = expr.get(ctx.exp(1));
        BigInteger x = a.subtract(b);
        expr.put(ctx, x);
    }

    @Override
    public void exitExpAdd(GnuLdParser.ExpAddContext ctx) {
        BigInteger a = expr.get(ctx.exp(0));
        BigInteger b = expr.get(ctx.exp(1));
        BigInteger x = a.add(b);
        expr.put(ctx, x);
    }

    @Override
    public void exitExpName(GnuLdParser.ExpNameContext ctx) {
        expr.put(ctx, BigInteger.ZERO);
    }

    @Override
    public void exitExpAddr(GnuLdParser.ExpAddrContext ctx) {
        expr.put(ctx, BigInteger.ZERO);
    }

    @Override
    public void exitExpSizeof(GnuLdParser.ExpSizeofContext ctx) {
        expr.put(ctx, BigInteger.ZERO);
    }

    @Override
    public void exitExpLengthExp(GnuLdParser.ExpLengthExpContext ctx) {
        LdLoader.MemoryArea ma = getMemoryArea(ctx.NAME().getText());
//        System.out.println("ma.length = " + ma.length);
        expr.put(ctx, ma.length);
    }

    @Override
    public void exitExpOrigin(GnuLdParser.ExpOriginContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.exitExpOrigin: " + ctx.getText());
        LdLoader.MemoryArea ma = getMemoryArea(ctx.NAME().getText());
//        System.out.println("ma.origin = " + ma.origin);
        expr.put(ctx, ma.origin);
    }

    private LdLoader.MemoryArea getMemoryArea(String name) {
        LdLoader.MemoryArea m = null;
        for (LdLoader.MemoryArea ma : memoryAreas) {
            if (ma.name.equals(name)) {
                m = ma;
            }
        }
        if (m == null) {
            throw new RuntimeException("No such memory area: " + name);
        }
        return m;
    }

    @Override
    public void enterMustbe_exp(GnuLdParser.Mustbe_expContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.enterMustbe_exp");
    }

    @Override
    public void exitMustbe_exp(GnuLdParser.Mustbe_expContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.exitMustbe_exp");

        expr.put(ctx, expr.get(ctx.exp()));
    }


    @Override
    public void enterOrigin_spec(GnuLdParser.Origin_specContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.enterOrigin_spec");
    }

    @Override
    public void exitOrigin_spec(GnuLdParser.Origin_specContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.exitOrigin_spec");
    }

    @Override
    public void enterLength_spec(GnuLdParser.Length_specContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.enterLength_spec");
    }

    @Override
    public void exitLength_spec(GnuLdParser.Length_specContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.exitLength_spec");
    }

    @Override
    public void enterMemory_spec(GnuLdParser.Memory_specContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.enterMemory_spec");
    }

    @Override
    public void exitMemory_spec(GnuLdParser.Memory_specContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.exitMemory_spec");
        LdLoader.MemoryArea ma = new LdLoader.MemoryArea();
        ma.name = ctx.NAME().getText();
        ma.attributes = attributes;
//        System.out.println("ctx.origin_spec() = " + ctx.origin_spec());
        ma.origin = expr.get(ctx.origin_spec().mustbe_exp());
        ma.length = expr.get(ctx.length_spec().mustbe_exp());
        System.out.println(ma);
        memoryAreas.add(ma);
    }

    LdLoader.MemoryAttribute attribute;
    boolean attributesInverted;
    Set<LdLoader.MemoryAttribute> attributes;

    @Override
    public void exitAttributes_opt(GnuLdParser.Attributes_optContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.exitAttributes_opt");
        attributes = new HashSet<>();
    }

    @Override
    public void enterAttributeInverted(GnuLdParser.AttributeInvertedContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.enterAttributeInverted");

        if (!attributes.isEmpty()) {
            throw new RuntimeException("Attributes for memory areas can only be attributesInverted (with '!') as the first character in a specification; foo(!rw), not foo(x!rw).");
        }
//                String name = ctx.name().getText();
        String name = ctx.NAME().getText();
//        System.out.println("ctx.ATTRIBUTE().getText() = " + name);

        attributesInverted = true;
    }

    @Override
    public void enterAttributeNormal(GnuLdParser.AttributeNormalContext ctx) {
//        System.out.println("ElfinfoGnuLdListener.enterAttributeNormal");

        String name = ctx.NAME().getText();
//        System.out.println("ctx.ATTRIBUTE().getText() = " + name);
        for (int i = 0; i < name.length(); i++) {
            attribute = LdLoader.MemoryAttribute.valueOf(String.valueOf(Character.toUpperCase(name.charAt(i))));
            attributes.add(attribute);
        }
        attributesInverted = false;
    }
}