/*
 * Copyright 2021 Tianmian Tech. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.welab.wefe.board.service.service.modelexport;

import java.util.List;

/**
 * Go
 *
 * @author aaron.li
 **/
public class XgboostGoLanguage extends BaseXgboostLanguage {

    @Override
    protected String preBuild2ClassificationsMethodSignNameCode(int treeNum, String initScore) {
        StringBuilder preMethodCode = new StringBuilder();
        preMethodCode.append("import \"math\"")
                .append("\n")
                .append("func score(input []float64) []float64 {")
                .append("\n")
                .append(METHOD_BODY_PLACEHOLDER)
                .append("\n")
                .append("}");
        return preMethodCode.toString();
    }

    @Override
    protected String build2ClassificationsResultLogicCode(int treeNum, String initScore, double learningRate) {
        StringBuilder methodCalcCode = new StringBuilder();
        String summaryVar = "s1";
        methodCalcCode.append(indentationByNodeLayer(1, false));
        methodCalcCode.append(generateVarDef(summaryVar))
                .append("\n")
                .append(indentationByNodeLayer(1, false))
                .append(summaryVar)
                .append(" = 1 / (1 + math.Exp(0 - (")
                .append(generateTreeSum(treeNum, initScore, learningRate))
                .append(")));")
                .append("\n")
                .append(build2ClassificationsReturnCode(summaryVar, initScore));

        return methodCalcCode.toString();
    }

    @Override
    protected String build2ClassificationsReturnCode(String varName, String initScore) {
        StringBuilder methodResultCode = new StringBuilder();
        methodResultCode.append(indentationByNodeLayer(1, false))
                .append("return []float64{1 - " + varName + ", " + varName + "}");

        return methodResultCode.toString();
    }

    @Override
    protected String buildExpFunction(List<String> treeVarNameList, String initScore, double learningRate) {
        StringBuilder code = new StringBuilder();
        code.append("math.Exp(0 - (")
                .append(generateTreeSum(treeVarNameList, initScore, learningRate))
                .append("))");

        return code.toString();
    }

    @Override
    protected String buildMultipleClassificationsReturnCode(int classificationsNum) {
        StringBuilder code = new StringBuilder();
        code.append(resultIndentationNum(2))
                .append("return []float64{");
        code.append(generateCodeByClassificationsNum(classificationsNum));
        code.append("}").append(lineEndSymbol());
        return code.toString();
    }


    @Override
    protected String resultIndentationNum(int num) {
        return super.resultIndentationNum(1);
    }


    @Override
    protected String indentationByNodeLayer(Node node, boolean initIndentation) {
        return super.indentationByNodeLayer(node, false);
    }

    @Override
    protected String indentationByNodeLayer(int layer, boolean initIndentation) {
        return super.indentationByNodeLayer(layer, false);
    }

    @Override
    protected String generateVarDef(String varName) {
        return "var " + varName + " float64";
    }

    @Override
    protected String lineEndSymbol() {
        return "";
    }

}
