package midend.llvm.value;

import java.util.ArrayList;
import java.util.HashSet;

import midend.llvm.instr.IrInstr;
import midend.llvm.instr.ReturnInstr;
import midend.llvm.type.IrBasicBlockType;

public class IrBasicBlock extends IrValue {
    private ArrayList<IrInstr> instrs;
    private IrFuncValue func;
    private ArrayList<IrBasicBlock> preds; //前驱
    private ArrayList<IrBasicBlock> succs; //后继
    private HashSet<IrBasicBlock> domied; //支配该节点
    private IrBasicBlock directDomi;
    private HashSet<IrBasicBlock> directDomies; //该节点直接支配
    private HashSet<IrBasicBlock> domiFrontier;

    public IrBasicBlock(String name, IrFuncValue func) {
        super(new IrBasicBlockType(), name);
        this.func = func;
        instrs = new ArrayList<>();
        preds = new ArrayList<>();
        succs = new ArrayList<>();
        domied = new HashSet<>();
        directDomi = null;
        directDomies = new HashSet<>();
        domiFrontier = new HashSet<>();
    }

    public void addInstr(IrInstr instr) {
        instrs.add(instr);
        instr.setBBlock(this);
    }

    public IrFuncValue getFunc() {
        return func;
    }

    public boolean isEmpty() {
        return instrs.isEmpty();
    }

    public boolean isEntry() {
        return this.func.getBBlock(0) == this;
    }

    public ArrayList<IrBasicBlock> getPreds() {
        return preds;
    }

    public ArrayList<IrBasicBlock> getSuccs() {
        return succs;
    }

    public String toString() {
        StringBuilder sb = new StringBuilder();
        sb.append(getName() + ":\n\t");
        for (IrInstr instr : instrs) {
            sb.append(instr.toString());
            if (instr != instrs.get(instrs.size() - 1)) {
                sb.append("\n\t");
            }
        }
        return sb.toString();
    }

    public boolean lastIsReturn() {
        if (instrs.isEmpty()) {
            return false;
        }
        return instrs.get(instrs.size() - 1) instanceof ReturnInstr;
    }

    public void clearCfg() {
        this.preds.clear();
        this.succs.clear();
        domied.clear();
        directDomi = null;
        directDomies.clear();
        domiFrontier.clear();
    }

    public ArrayList<IrInstr> getInstrs() {
        return instrs;
    }

    public void addPred(IrBasicBlock bb) {
        this.preds.add(bb);
    }

    public void addSucc(IrBasicBlock bb) {
        this.succs.add(bb);
    }

    public void addDomied(IrBasicBlock bb) {
        this.domied.add(bb);
    }

    public void addDirectDomies(IrBasicBlock bb) {
        this.directDomies.add(bb);
    }

    public void addDomiFrontier(IrBasicBlock bb) {
        this.domiFrontier.add(bb);
    }

    public void setDirectDomi(IrBasicBlock bb) {
        this.directDomi = bb;
    }

    public HashSet<IrBasicBlock> getDomied() {
        return domied;
    }

    public IrBasicBlock getDirectDomi() {
        return this.directDomi;
    }
}