package org.shedlang.compiler.patio;

import org.pcollections.PVector;
import org.shedlang.compiler.patio.instructions.PatioInstruction;
import org.shedlang.compiler.patio.types.PatioType;
import org.shedlang.compiler.sources.Source;
import org.shedlang.compiler.sources.Sources;
import org.shedlang.compiler.util.P;

import java.util.List;

public record PatioFunctionDefinition(
    String name,
    PatioVisibility visibility,
    List<PatioLocal> locals,
    List<PatioType> returnTypes,
    List<PatioInstruction> body,
    Source source
) implements PatioCompilationUnitElement {
    public Iterable<PatioLocal> params() {
        return locals.stream()
            .filter(local -> local.localType() == PatioLocalType.PARAM)
            .toList();
    }

    public static Builder builder() {
        return new Builder(
            "f",
            PatioVisibility.PRIVATE,
            P.vector(),
            P.vector(),
            P.vector()
        );
    }

    public record Builder(
        String name,
        PatioVisibility visibility,
        PVector<PatioLocal> locals,
        PVector<PatioType> returnTypes,
        PVector<PatioInstruction> body
    ) {
        public Builder withName(String name) {
            return new Builder(
                name,
                this.visibility,
                this.locals,
                this.returnTypes,
                this.body
            );
        }

        public Builder withVisibility(PatioVisibility visibility) {
            return new Builder(
                this.name,
                visibility,
                this.locals,
                this.returnTypes,
                this.body
            );
        }

        public Builder addLocal(PatioLocal local) {
            return new Builder(
                this.name,
                this.visibility,
                this.locals.plus(local),
                this.returnTypes,
                this.body
            );
        }

        public Builder addBodyInstruction(PatioInstruction instruction) {
            return new Builder(
                this.name,
                this.visibility,
                this.locals,
                this.returnTypes,
                this.body.plus(instruction)
            );
        }

        public Builder addReturnType(PatioType returnType) {
            return new Builder(
                this.name,
                this.visibility,
                this.locals,
                this.returnTypes.plus(returnType),
                this.body
            );
        }

        public PatioFunctionDefinition build() {
            return new PatioFunctionDefinition(
                this.name,
                this.visibility,
                this.locals,
                this.returnTypes,
                this.body,
                Sources.NULL
            );
        }
    }
}