package targetast;

import de.dhbwstuttgart.core.JavaTXCompiler;
import de.dhbwstuttgart.syntaxtree.ClassOrInterface;
import de.dhbwstuttgart.syntaxtree.Field;
import de.dhbwstuttgart.syntaxtree.Method;
import de.dhbwstuttgart.syntaxtree.type.RefType;
import de.dhbwstuttgart.syntaxtree.type.TypePlaceholder;
import de.dhbwstuttgart.target.generate.ASTToTargetAST;
import static de.dhbwstuttgart.target.generate.ASTToTargetAST.OBJECT;
import de.dhbwstuttgart.target.generate.Bound;
import static de.dhbwstuttgart.target.generate.Bound.*;
import de.dhbwstuttgart.target.generate.BoundsList;
import de.dhbwstuttgart.target.generate.GenericsResult;
import org.junit.Ignore;
import org.junit.Test;
import static org.junit.Assert.*;

import java.io.File;
import java.io.IOException;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.List;

@Ignore("TODO: Rewrite with the new algorithm")
public class TestGenerics {
    private static final String rootDirectory = System.getProperty("user.dir") + "/resources/insertGenerics/javFiles/";
    private static final String bytecodeDirectory = System.getProperty("user.dir") + "targetTest";

    private record Result(List<GenericsResult> genericsResults, ClassOrInterface clazz) {
        Method findMethod(String name) {
            return clazz.getMethods().stream().filter(m -> m.getName().equals(name)).findFirst().orElse(null);
        }

        Field findField(String name) {
            return clazz.getFieldDecl().stream().filter(field -> field.getName().equals(name)).findFirst().orElse(null);
        }
    }

    private static void assertStrictlyEquals(BoundsList a, BoundsList b) {
        assertEquals(a.base, b.base);
        assertEquals(a, b);
    }

    private static void assertStrictlyNotEquals(BoundsList a, BoundsList b) {
        assertNotEquals(a.base, b.base);
    }

    private static Result computeGenerics(String filename) throws IOException, ClassNotFoundException {
        var file = Path.of(rootDirectory + filename).toFile();
        var compiler = new JavaTXCompiler(List.of(file), List.of(file.getParentFile()), new File(bytecodeDirectory));
        var inference = compiler.typeInference(file);
        compiler.generateBytecode(new File(bytecodeDirectory), inference);
        var sf = compiler.sourceFiles.get(file);
        var clazz = sf.getClasses().get(0);
        return new Result(compiler.getGeneratedGenerics().get(sf), clazz);
    }

    @Test
    public void testAny() throws Exception {
        var result = computeGenerics("TestAny.jav");
        var anyMethod = result.findMethod("anyMethod");
        var otherMethod = result.findMethod("otherMethod");
        var a = result.findField("a");
        var b = result.findField("b");

        var generics = result.genericsResults.get(0);
        assertEquals(1, generics.get(anyMethod).size());
        assertEquals(2, generics.get(result.clazz).size());

        var ECK1 = generics.getBounds(otherMethod.getParameterList().getParameterAt(0).getType(), result.clazz, anyMethod);
        var ECK2 = generics.getBounds(otherMethod.getReturnType(), result.clazz, anyMethod);
        var ECKChain = new BoundsList(onClass(OBJECT));
        assertStrictlyEquals(ECK1, ECK2);
        assertEquals(ECK2, generics.getBounds(b.getType(), result.clazz));

        var M = generics.getBounds(a.getType(), result.clazz);
        var MChain = new BoundsList(onClass("ECK"), onClass(OBJECT));
        assertEquals(M, MChain);
    }

    @Test
    public void testClassField() throws Exception {
        var result = computeGenerics("TestClassField.jav");
        var fReturn = result.findMethod("fReturn");

        var generics = result.genericsResults.get(0);
        assertEquals(1, generics.get(result.clazz).size());
        assertEquals(0, generics.get(fReturn).size());

        var N = generics.getBounds(fReturn.getReturnType(), result.clazz);
        var NChain = new BoundsList(onClass(OBJECT));
        assertEquals(N, NChain);
    }

    @Test
    public void testContraVariant() throws Exception {
        var result = computeGenerics("TestContraVariant.jav");
        var m = result.findMethod("m");
        var main = result.findMethod("main");

        var generics = result.genericsResults.get(0);
        assertEquals(0, generics.get(result.clazz).size());
        assertEquals(3, generics.get(m).size());
        assertEquals(3, generics.get(main).size());

        {
            var AJ = generics.getBounds(m.getParameterList().getParameterAt(0).getType(), result.clazz, m);
            var AK = generics.getBounds(m.getParameterList().getParameterAt(1).getType(), result.clazz, m);
            var KWU = generics.getBounds(((RefType) generics.resolve(m.getReturnType())).getParaList().get(0), result.clazz, m);
            var AK2 = generics.getBounds(((RefType) generics.resolve(m.getReturnType())).getParaList().get(1), result.clazz, m);

            assertStrictlyEquals(AK, AK2);
            assertStrictlyNotEquals(AJ, KWU);
            var NChain = new BoundsList(onMethod(OBJECT));
            assertEquals(AJ, NChain);
            assertEquals(AK, NChain);
            assertEquals(KWU, NChain);
        }

        {
            var O = generics.getBounds(main.getParameterList().getParameterAt(0).getType(), result.clazz, main);
            var P = generics.getBounds(main.getParameterList().getParameterAt(1).getType(), result.clazz, main);
            var KWQ = generics.getBounds(((RefType) generics.resolve(main.getReturnType())).getParaList().get(1), result.clazz, main);
            var O2 = generics.getBounds(((RefType) generics.resolve(main.getReturnType())).getParaList().get(0), result.clazz, main);

            assertStrictlyEquals(O, O2);
            assertStrictlyNotEquals(P, KWQ);
            var NChain = new BoundsList(onMethod(OBJECT));
            assertEquals(O, NChain);
            assertEquals(P, NChain);
            assertEquals(KWQ, NChain);
        }
    }

    @Test
    public void testGGFinder() throws Exception {
        var result = computeGenerics("TestGGFinder.jav");
        var id = result.findMethod("id");
        var setA = result.findMethod("setA");
        var m = result.findMethod("m");
        var a = result.findField("a");

        var generics = result.genericsResults.get(0);
        assertEquals(1, generics.get(result.clazz).size());
        assertEquals(2, generics.get(id).size());
        assertEquals(1, generics.get(setA).size());
        assertEquals(2, generics.get(m).size());

        var R = generics.getBounds(a.getType(), result.clazz);
        var RChain =  new BoundsList(onClass(OBJECT));
        assertEquals(R, RChain);

        var O = generics.getBounds(id.getParameterList().getParameterAt(0).getType(), result.clazz, id);
        var AB = generics.getBounds(id.getReturnType(), result.clazz, id);
        assertEquals(O, AB);
        assertEquals(AB, new BoundsList(onMethod(OBJECT)));

        var S = generics.getBounds(setA.getParameterList().getParameterAt(0).getType(), result.clazz, setA);
        assertEquals(S, RChain);
        assertEquals(generics.getBounds(setA.getReturnType(), result.clazz, setA), RChain);

        var X = generics.getBounds(m.getParameterList().getParameterAt(0).getType(), result.clazz, m);
        var Y = generics.getBounds(m.getParameterList().getParameterAt(1).getType(), result.clazz, m);
        var XChain = new BoundsList(onMethod(OBJECT));
        assertEquals(X, XChain);
        assertEquals(Y, X);
    }

    @Test
    public void testLocalVarLambda() throws Exception {
        var result = computeGenerics("TestLocalVarLambda.jav");
        // TODO Generics of lambdas
    }

    @Test
    public void testMutualRecursion() throws Exception {
        var result = computeGenerics("TestMutualRecursion.jav");
        var id = result.findMethod("id");
        var m = result.findMethod("m");
        var main = result.findMethod("main");
        var a = result.findField("a");

        var generics = result.genericsResults.get(0);
        assertEquals(1, generics.get(result.clazz).size());
        assertEquals(2, generics.get(id).size());
        assertEquals(2, generics.get(m).size());
        assertEquals(3, generics.get(main).size());

        var N = generics.getBounds(a.getType(), result.clazz);
        assertEquals(N, new BoundsList(onClass(OBJECT)));

        var P = generics.getBounds(id.getParameterList().getParameterAt(0).getType(), result.clazz, id);
        var O = generics.getBounds(id.getReturnType(), result.clazz, id);
        assertEquals(P, O);
        assertEquals(O, new BoundsList(onMethod(OBJECT)));

        assertEquals(generics.resolve(m.getParameterList().getParameterAt(0).getType()), generics.resolve(m.getReturnType()));
        var Y = generics.getBounds(m.getParameterList().getParameterAt(0).getType(), result.clazz, m);
        var AA = generics.getBounds(m.getParameterList().getParameterAt(1).getType(), result.clazz, m);
        assertEquals(Y, AA);
        assertEquals(AA, new BoundsList(onMethod(OBJECT)));

        var AI = generics.getBounds(m.getParameterList().getParameterAt(0).getType(), result.clazz, m);
        var AJ = generics.getBounds(m.getParameterList().getParameterAt(1).getType(), result.clazz, m);
        var AH = generics.getBounds(m.getReturnType(), result.clazz, m);
        assertEquals(AI, AJ);
        assertEquals(AJ, AH);
        assertEquals(AH, new BoundsList(onMethod(OBJECT)));
    }

    @Test
    public void testReturnVar() throws Exception {
        var result = computeGenerics("TestReturnVar.jav");
        var anyMethod = result.findMethod("anyMethod");

        var generics = result.genericsResults.get(0);
        assertEquals(1, generics.get(anyMethod).size());

        var M = generics.getBounds(anyMethod.getReturnType(), result.clazz, anyMethod);
        assertEquals(M, new BoundsList(onMethod(OBJECT)));
    }

    @Test
    public void testSecondLineOfClassConstraints() throws Exception {
        var result = computeGenerics("TestSecondLineOfClassConstraints.jav");
        var a = result.findField("a");
        var b = result.findField("b");
        var anyMethod = result.findMethod("anyMethod");
        var otherMethod = result.findMethod("otherMethod");

        var generics = result.genericsResults.get(0);
        var M = generics.getBounds(a.getType(), result.clazz);
        var DYX = generics.getBounds(b.getType(), result.clazz);
        var MChain = new BoundsList(onClass("DYX"), onClass(OBJECT));
        var DYXChain = new BoundsList(onClass(OBJECT));
        assertEquals(M, MChain);

        var Q = generics.getBounds(anyMethod.getReturnType(), result.clazz, anyMethod);
        assertEquals(Q, new BoundsList(onMethod(OBJECT)));

        System.out.println(otherMethod.getReturnType());
        var DYX2 = generics.getBounds(otherMethod.getReturnType(), result.clazz, otherMethod);
        assertEquals(DYX, DYX2);
        assertEquals(DYX, generics.getBounds(otherMethod.getReturnType(), result.clazz, otherMethod));
    }

    @Test
    public void testThreeArgs() throws Exception {
        var result = computeGenerics("TestThreeArgs.jav");
    }

    @Test
    public void testTPHsAndGenerics() throws Exception {
        var result = computeGenerics("TestTPHsAndGenerics.jav");
        var id2 = result.findMethod("id2");
        var m = result.findMethod("m");
        var m2 = result.findMethod("m2");

        var generics = result.genericsResults.get(0);
        var U = generics.getBounds(id2.getParameterList().getParameterAt(0).getType(), result.clazz, id2);
        var FPT = generics.getBounds(id2.getReturnType(), result.clazz, id2);
        assertEquals(U, new BoundsList(onMethod("FPT"), onClass(OBJECT)));
        assertEquals(FPT, new BoundsList(onClass(OBJECT)));

        var AA = generics.getBounds(m.getReturnType(), result.clazz, m);
        var AC = generics.getBounds(m.getParameterList().getParameterAt(1).getType(), result.clazz, m);
        assertEquals(AA, new BoundsList(onMethod(OBJECT)));
        assertEquals(AC, new BoundsList(onMethod(OBJECT)));

        var AH = generics.getBounds(m2.getReturnType(), result.clazz, m2);
        var AL = generics.getBounds(m2.getParameterList().getParameterAt(0).getType(), result.clazz, m2);
        assertEquals(AH, new BoundsList(onMethod(OBJECT)));
        assertEquals(AH, AL);
    }

    @Test
    public void testTwoArgs() throws Exception {
        var result = computeGenerics("TestTwoArgs.jav");

        var a = result.findField("a");
        var id = result.findMethod("id");
        var setA = result.findMethod("setA");
        var m = result.findMethod("m");
        var main = result.findMethod("main");

        var generics = result.genericsResults.get(0);
        var AO = generics.getBounds(a.getType(), result.clazz);
        var AOBound = new BoundsList(
                onClass("Y"),
                onClass("AK"),
                onClass("AE"),
                onClass(OBJECT)
        );
        assertEquals(AO, AOBound);

        var S = generics.getBounds(setA.getParameterList().getParameterAt(0).getType(), result.clazz, setA);
        var c = new ArrayList<Bound>();
        c.add(onMethod("AO"));
        c.addAll(AOBound);
        var SChain = new BoundsList(c);
        assertEquals(S, SChain);

        var Y = generics.getBounds(m.getParameterList().getParameterAt(1).getType(), result.clazz, m);
        var YChain = new BoundsList(onMethod("AE"), onClass(OBJECT));
        var AE = generics.getBounds(m.getReturnType(), result.clazz, m);
        assertEquals(Y, YChain);
        assertEquals(AE, new BoundsList(onClass(OBJECT)));

        // TODO main seems to change between runs
        /*var AE2 = generics.getBounds(main.getReturnType(), result.clazz, main);
        var AF = generics.getBounds(main.getParameterList().getParameterAt(0).getType(), result.clazz, main);
        var AG = generics.getBounds(main.getParameterList().getParameterAt(1).getType(), result.clazz, main);
        assertEquals(AE, AE2));
        assertEquals(AF, new BoundsList(onMethod("AK"), onMethod("AE"), onClass(OBJECT))));
        assertEquals(AG, SChain));*/
    }

    @Test
    public void testTwoArgs2() throws Exception {
        var result = computeGenerics("TestTwoArgs2.jav");
        // TODO Test generics
    }

    @Test
    public void testTwoCalls() throws Exception {
        var result = computeGenerics("TestTwoCalls.jav");
        var id = result.findMethod("id");
        var main = result.findMethod("main");

        var generics = result.genericsResults.get(0);
        var O = generics.getBounds(id.getReturnType(), result.clazz, id);
        var O2 = generics.getBounds(id.getParameterList().getParameterAt(0).getType(), result.clazz, id);
        assertStrictlyEquals(O, O2);
        assertEquals(O2, new BoundsList(onMethod(OBJECT)));

        // TODO Maybe test in other ways if the parameter generics equals the return generics
        var S = generics.getBounds(main.getReturnType(), result.clazz, main);
        var S2 = generics.getBounds(main.getParameterList().getParameterAt(1).getType(), result.clazz, main);
        var T = generics.getBounds(main.getParameterList().getParameterAt(0).getType(), result.clazz, main);
        assertStrictlyEquals(S, S2);
        assertEquals(S2, new BoundsList(onMethod(OBJECT)));
        assertEquals(T, new BoundsList(onMethod(OBJECT)));
    }

    @Test
    public void testVector() throws Exception {
        var result = computeGenerics("TestVector.jav");
        var m = result.findMethod("m");
        var id = result.findMethod("id");

        var generics = result.genericsResults.get(0);
        var par1 = generics.resolve(m.getParameterList().getParameterAt(0).getType());
        var par2 = generics.resolve(m.getParameterList().getParameterAt(1).getType());

        var S = generics.getBounds(((RefType) par1).getParaList().get(0), result.clazz, m);
        var ACM = generics.getBounds(((RefType) par2).getParaList().get(0), result.clazz, m);
        assertEquals(S, new BoundsList(onMethod("V"), onMethod(OBJECT)));
        assertEquals(ACM, new BoundsList(onMethod(OBJECT)));

        var Y = generics.getBounds(id.getParameterList().getParameterAt(0).getType(), result.clazz, id);
        assertEquals(Y, new BoundsList(onMethod(OBJECT)));
        assertEquals(Y, generics.getBounds(id.getReturnType(), result.clazz, id));
    }

    @Test
    public void testVectorArg() throws Exception {
        var result = computeGenerics("TestVectorArg.jav");
        var add = result.findMethod("add");
        var main = result.findMethod("main");

        var generics = result.genericsResults.get(0);
        var par1 = generics.resolve(add.getParameterList().getParameterAt(0).getType());
        var ACK = generics.getBounds(((RefType) par1).getParaList().get(0), result.clazz, add);
        var O = generics.getBounds(add.getParameterList().getParameterAt(1).getType(), result.clazz, add);
        assertEquals(ACK, new BoundsList(onMethod(OBJECT)));
        assertEquals(O, new BoundsList(onMethod("ACK"), onMethod(OBJECT)));

        var par2 = generics.resolve(main.getParameterList().getParameterAt(0).getType());
        var ACK2 = generics.getBounds(((RefType) par2).getParaList().get(0), result.clazz, add);
        var V = generics.getBounds(add.getParameterList().getParameterAt(1).getType(), result.clazz, add);
        assertStrictlyEquals(ACK2, ACK);
        assertEquals(V, O);
    }

    @Test
    public void testVoidMeth() throws Exception {
        var result = computeGenerics("TestVoidMeth.jav");
    }

    @Test
    public void testAssign() throws Exception {
        // TODO Check generics
        var result = computeGenerics("TestAssign.jav");
    }
}