package com.alibaba.qlexpress4.runtime.instruction;

import com.alibaba.qlexpress4.QLOptions;
import com.alibaba.qlexpress4.exception.ErrorReporter;
import com.alibaba.qlexpress4.exception.QLErrorCodes;
import com.alibaba.qlexpress4.runtime.QContext;
import com.alibaba.qlexpress4.runtime.QResult;
import com.alibaba.qlexpress4.runtime.data.convert.ObjTypeConvertor;
import com.alibaba.qlexpress4.utils.PrintlnUtils;

import java.util.function.Consumer;

/**
 * Operation: define a symbol in local scope
 * Input: 1 symbol init value
 * Output: 0
 *
 * Author: DQinYuan
 */
public class DefineLocalInstruction extends QLInstruction {
    
    private final String variableName;
    
    private final Class<?> defineClz;
    
    public DefineLocalInstruction(ErrorReporter errorReporter, String variableName, Class<?> defineClz) {
        super(errorReporter);
        this.variableName = variableName;
        this.defineClz = defineClz;
    }
    
    @Override
    public QResult execute(QContext qContext, QLOptions qlOptions) {
        Object initValue = qContext.pop().get();
        ObjTypeConvertor.QConverted qlConvertResult = ObjTypeConvertor.cast(initValue, defineClz);
        if (!qlConvertResult.isConvertible()) {
            throw errorReporter.reportFormat(QLErrorCodes.INCOMPATIBLE_ASSIGNMENT_TYPE.name(),
                QLErrorCodes.INCOMPATIBLE_ASSIGNMENT_TYPE.getErrorMsg(),
                defineClz.getName(),
                initValue == null ? "null" : initValue.getClass().getName());
        }
        qContext.defineLocalSymbol(variableName, defineClz, qlConvertResult.getConverted());
        return QResult.NEXT_INSTRUCTION;
    }
    
    @Override
    public int stackInput() {
        return 1;
    }
    
    @Override
    public int stackOutput() {
        return 0;
    }
    
    @Override
    public void println(int index, int depth, Consumer<String> debug) {
        PrintlnUtils.printlnByCurDepth(depth, index + ": DefineLocal " + variableName, debug);
    }
}
