/*
 * Copyright Red Hat, Inc. and/or its affiliates
 * and other contributors as indicated by the @author tags and
 * the COPYRIGHT.txt file distributed with this work.
 *
 * 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 org.teiid.translator.odata;

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

import org.teiid.language.Argument;
import org.teiid.language.Argument.Direction;
import org.teiid.language.Call;
import org.teiid.language.SQLConstants.Tokens;
import org.teiid.language.visitor.HierarchyVisitor;
import org.teiid.metadata.Column;
import org.teiid.metadata.Procedure;
import org.teiid.metadata.ProcedureParameter;
import org.teiid.metadata.RuntimeMetadata;
import org.teiid.metadata.Schema;
import org.teiid.metadata.Table;
import org.teiid.translator.TranslatorException;
import org.teiid.util.WSUtil;

public class ODataProcedureVisitor extends HierarchyVisitor {
	protected ODataExecutionFactory executionFactory;
	protected RuntimeMetadata metadata;
	protected ArrayList<TranslatorException> exceptions = new ArrayList<TranslatorException>();
	private StringBuilder buffer = new StringBuilder();
	private String method = "GET"; //$NON-NLS-1$
	private String returnEntityTypeName;
	private boolean returnsTable;
	private Procedure procedure;
	private String returnType;
	private Class<?> returnTypeClass;
	private boolean isComplexReturnType;
	private Table entity;
	private List<Column> returnColumns;

	public ODataProcedureVisitor(ODataExecutionFactory executionFactory,
			RuntimeMetadata metadata) {
		this.executionFactory = executionFactory;
		this.metadata = metadata;
	}

	@Override
    public void visit(Call obj) {
		Procedure proc = obj.getMetadataObject();
		this.method = proc.getProperty(ODataMetadataProcessor.HTTP_METHOD, false);

		this.procedure = proc;
		this.buffer.append(obj.getProcedureName());
        final List<Argument> params = obj.getArguments();
        if (params != null && params.size() != 0) {
        	this.buffer.append("?"); //$NON-NLS-1$
            Argument param = null;
            StringBuilder temp = new StringBuilder();
            for (int i = 0; i < params.size(); i++) {
                param = params.get(i);
                if (param.getDirection() == Direction.IN || param.getDirection() == Direction.INOUT) {
                    if (i != 0) {
                        this.buffer.append("&"); //$NON-NLS-1$
                    }
                    this.buffer.append(WSUtil.httpURLEncode(param.getMetadataObject().getName()));
                    this.buffer.append(Tokens.EQ);
                    this.executionFactory.convertToODataInput(param.getArgumentValue(), temp);
                    this.buffer.append(WSUtil.httpURLEncode(temp.toString()));
                    temp.setLength(0);
                }
            }
        }

        // this is collection based result
        if(proc.getResultSet() != null) {
        	this.returnsTable = true;
        	this.returnEntityTypeName = proc.getProperty(ODataMetadataProcessor.ENTITY_TYPE, false);
        	this.entity = getTableWithEntityType(proc.getParent(), returnEntityTypeName);
       		this.isComplexReturnType = ( this.entity == null);
       		this.returnColumns = proc.getResultSet().getColumns();
        }
        else {
        	for (ProcedureParameter param:proc.getParameters()) {
        		if (param.getType().equals(ProcedureParameter.Type.ReturnValue)) {
        			this.returnType = param.getRuntimeType();
        			this.returnTypeClass = param.getJavaType();
        		}
        	}
        }
	}
	
	Table getTableWithEntityType(Schema schema, String entityType) {
		for (Table t:schema.getTables().values()) {
			if (entityType.equals(t.getProperty(ODataMetadataProcessor.ENTITY_TYPE, false))) {
				return t;
			}
		}
		return null;
	}

	public String buildURL() {
		return this.buffer.toString();
	}

	public String getMethod() {
		return this.method;
	}

	public String getReturnEntityTypeName() {
		return this.returnEntityTypeName;
	}

	public Table getTable() {
		return this.entity;
	}
	
	public boolean hasCollectionReturn() {
		return this.returnsTable;
	}
	
	public Column[] getReturnColumns() {
		return this.returnColumns.toArray(new Column[this.returnColumns.size()]);
	}

	public boolean isReturnComplexType() {
		return this.isComplexReturnType;
	}	

	public Procedure getProcedure() {
		return this.procedure;
	}

	public String getReturnType() {
		return this.returnType;
	}

	public Class<?>getReturnTypeClass() {
		return this.returnTypeClass;
	}

}
