/**
 * Copyright (c) 2015 Cisco Systems, Inc. and others.  All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
 * and is available at http://www.eclipse.org/legal/epl-v10.html
 */
package org.opendaylight.yangtools.yang.parser.impl;

import java.util.ArrayList;
import java.util.List;

import org.antlr.v4.runtime.tree.ParseTree;
import org.opendaylight.yangtools.antlrv4.code.gen.YangStatementParser;
import org.opendaylight.yangtools.antlrv4.code.gen.YangStatementParserBaseListener;
import org.opendaylight.yangtools.yang.common.QName;
import org.opendaylight.yangtools.yang.common.YangConstants;
import org.opendaylight.yangtools.yang.parser.spi.source.PrefixToModule;
import org.opendaylight.yangtools.yang.parser.spi.source.QNameToStatementDefinition;
import org.opendaylight.yangtools.yang.parser.spi.source.SourceException;
import org.opendaylight.yangtools.yang.parser.spi.source.StatementSourceReference;
import org.opendaylight.yangtools.yang.parser.spi.source.StatementWriter;
import org.opendaylight.yangtools.yang.parser.stmt.rfc6020.Utils;

public class YangStatementParserListenerImpl extends YangStatementParserBaseListener {

    private StatementWriter writer;
    private StatementSourceReference ref;
    private QNameToStatementDefinition stmtDef;
    private PrefixToModule prefixes;
    private List<String> toBeSkipped = new ArrayList<>();

    public YangStatementParserListenerImpl(StatementSourceReference ref) {
        this.ref = ref;
    }

    public void setAttributes(StatementWriter writer, QNameToStatementDefinition stmtDef) {
        this.writer = writer;
        this.stmtDef = stmtDef;
    }

    public void setAttributes(StatementWriter writer, QNameToStatementDefinition stmtDef, PrefixToModule prefixes) {
        this.writer = writer;
        this.stmtDef = stmtDef;
        this.prefixes = prefixes;
    }

    @Override
    public void enterStatement(YangStatementParser.StatementContext ctx) {
        boolean action = true;
        for (int i = 0; i < ctx.getChildCount(); i++) {
            ParseTree child = ctx.getChild(i);
            if (child instanceof YangStatementParser.KeywordContext) {
                try {
                    QName identifier = new QName(YangConstants.RFC6020_YIN_NAMESPACE,
                            ((YangStatementParser.KeywordContext) child).children.get(0).getText());
                    if (stmtDef != null && stmtDef.get(identifier) != null && toBeSkipped.isEmpty()) {
                        writer.startStatement(identifier, ref);
                    } else {
                        action = false;
                        toBeSkipped.add(((YangStatementParser.KeywordContext) child).children.get(0).getText());
                    }
                } catch (SourceException e) {
                    e.printStackTrace();
                }
            } else if (child instanceof YangStatementParser.ArgumentContext) {
                try {
                    if (action)
                        writer.argumentValue(
                                Utils.stringFromStringContext((YangStatementParser.ArgumentContext) child), ref);
                    else
                        action = true;
                } catch (SourceException e) {
                    e.printStackTrace();
                }
            }

        }
    }

    @Override
    public void exitStatement(YangStatementParser.StatementContext ctx) {
        for (int i = 0; i < ctx.getChildCount(); i++) {
            ParseTree child = ctx.getChild(i);
            if (child instanceof YangStatementParser.KeywordContext) {
                try {
                    String statementName = ((YangStatementParser.KeywordContext) child).children.get(0).getText();
                    QName identifier = new QName(YangConstants.RFC6020_YIN_NAMESPACE, statementName);
                    if (stmtDef != null && stmtDef.get(identifier) != null && toBeSkipped.isEmpty()) {
                        writer.endStatement(ref);
                    }

                    if (toBeSkipped.contains(statementName)) {
                        toBeSkipped.remove(statementName);
                    }
                } catch (SourceException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}