content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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.datastax.oss.driver.internal.querybuilder.schema;
  
  import com.datastax.oss.driver.api.core.CqlIdentifier;
  import com.datastax.oss.driver.api.core.type.DataType;
  import com.datastax.oss.driver.api.querybuilder.schema.CreateFunctionEnd;
  import com.datastax.oss.driver.api.querybuilder.schema.CreateFunctionStart;
  import com.datastax.oss.driver.api.querybuilder.schema.CreateFunctionWithLanguage;
  import com.datastax.oss.driver.api.querybuilder.schema.CreateFunctionWithNullOption;
  import com.datastax.oss.driver.api.querybuilder.schema.CreateFunctionWithType;
  import com.datastax.oss.driver.internal.querybuilder.CqlHelper;
  import com.datastax.oss.driver.internal.querybuilder.ImmutableCollections;
  import com.datastax.oss.driver.shaded.guava.common.collect.ImmutableMap;
  import edu.umd.cs.findbugs.annotations.NonNull;
  import edu.umd.cs.findbugs.annotations.Nullable;
  import java.util.Map;
  import net.jcip.annotations.Immutable;
  
  @Immutable
  public class DefaultCreateFunction
      implements CreateFunctionStart,
          CreateFunctionWithNullOption,
          CreateFunctionWithType,
          CreateFunctionWithLanguage,
          CreateFunctionEnd {
  
    private final CqlIdentifier keyspace;
    private final CqlIdentifier functionName;
    private boolean orReplace;
    private boolean ifNotExists;
    private final ImmutableMap<CqlIdentifier, DataType> parameters;
    private boolean returnsNullOnNull;
    private final DataType returnType;
    private final String language;
    private final String functionBody;
  
    public DefaultCreateFunction(@NonNull CqlIdentifier functionName) {
      this(null, functionName);
    }
  
    public DefaultCreateFunction(
        @Nullable CqlIdentifier keyspace, @NonNull CqlIdentifier functionName) {
      this(keyspace, functionName, false, false, ImmutableMap.of(), false, null, null, null);
    }
  
    public DefaultCreateFunction(
        @Nullable CqlIdentifier keyspace,
        @NonNull CqlIdentifier functionName,
        boolean orReplace,
        boolean ifNotExists,
        @NonNull ImmutableMap<CqlIdentifier, DataType> parameters,
        boolean returnsNullOnNull,
        @Nullable DataType returns,
        @Nullable String language,
        @Nullable String functionBody) {
      this.keyspace = keyspace;
      this.functionName = functionName;
      this.orReplace = orReplace;
      this.ifNotExists = ifNotExists;
      this.parameters = parameters;
      this.returnsNullOnNull = returnsNullOnNull;
      this.returnType = returns;
      this.language = language;
      this.functionBody = functionBody;
    }
  
    @NonNull
    @Override
    public String asCql() {
      StringBuilder builder = new StringBuilder();
  
      builder.append("CREATE ");
      if (orReplace) {
        builder.append("OR REPLACE ");
      }
      builder.append("FUNCTION ");
  
      if (ifNotExists) {
        builder.append("IF NOT EXISTS ");
      }
      CqlHelper.qualify(keyspace, functionName, builder);
  
      builder.append(" (");
  
      boolean first = true;
      for (Map.Entry<CqlIdentifier, DataType> param : parameters.entrySet()) {
        if (first) {
          first = false;
        } else {
          builder.append(',');
        }
        builder
            .append(param.getKey().asCql(true))
            .append(' ')
            .append(param.getValue().asCql(false, true));
      }
      builder.append(')');
      if (returnsNullOnNull) {
        builder.append(" RETURNS NULL");
      } else {
        builder.append(" CALLED");
      }
  
      builder.append(" ON NULL INPUT");
  
      if (returnType == null) {
        // return type has not been provided yet.
        return builder.toString();
      }
  
      builder.append(" RETURNS ");
      builder.append(returnType.asCql(false, true));
  
      if (language == null) {
        // language has not been provided yet.
        return builder.toString();
      }
  
      builder.append(" LANGUAGE ");
      builder.append(language);
  
      if (functionBody == null) {
        // body has not been provided yet.
        return builder.toString();
      }
  
      builder.append(" AS ");
      builder.append(functionBody);
      return builder.toString();
    }
  
    @Override
    public String toString() {
      return asCql();
    }
  
    @NonNull
    @Override
    public CreateFunctionEnd as(@NonNull String functionBody) {
      return new DefaultCreateFunction(
          keyspace,
          functionName,
          orReplace,
          ifNotExists,
          parameters,
          returnsNullOnNull,
          returnType,
          language,
          functionBody);
    }
  
    @NonNull
    @Override
    public CreateFunctionWithLanguage withLanguage(@NonNull String language) {
      return new DefaultCreateFunction(
          keyspace,
          functionName,
          orReplace,
          ifNotExists,
          parameters,
          returnsNullOnNull,
          returnType,
          language,
          functionBody);
    }
  
    @NonNull
    @Override
    public CreateFunctionWithType returnsType(@NonNull DataType returnType) {
      return new DefaultCreateFunction(
          keyspace,
          functionName,
          orReplace,
          ifNotExists,
          parameters,
          returnsNullOnNull,
          returnType,
          language,
          functionBody);
    }
  
    @NonNull
    @Override
    public CreateFunctionStart ifNotExists() {
      return new DefaultCreateFunction(
          keyspace,
          functionName,
          orReplace,
          true,
          parameters,
          returnsNullOnNull,
          returnType,
          language,
          functionBody);
    }
  
    @NonNull
    @Override
    public CreateFunctionStart orReplace() {
      return new DefaultCreateFunction(
          keyspace,
          functionName,
          true,
          ifNotExists,
          parameters,
          returnsNullOnNull,
          returnType,
          language,
          functionBody);
    }
  
    @NonNull
    @Override
    public CreateFunctionStart withParameter(
        @NonNull CqlIdentifier paramName, @NonNull DataType paramType) {
      return new DefaultCreateFunction(
          keyspace,
          functionName,
          orReplace,
          ifNotExists,
          ImmutableCollections.append(parameters, paramName, paramType),
          returnsNullOnNull,
          returnType,
          language,
          functionBody);
    }
  
    @NonNull
    @Override
    public CreateFunctionWithNullOption returnsNullOnNull() {
      return new DefaultCreateFunction(
          keyspace,
          functionName,
          orReplace,
          ifNotExists,
          parameters,
          true,
          returnType,
          language,
          functionBody);
    }
  
    @NonNull
    @Override
    public CreateFunctionWithNullOption calledOnNull() {
      return new DefaultCreateFunction(
          keyspace,
          functionName,
          orReplace,
          ifNotExists,
          parameters,
          false,
          returnType,
          language,
          functionBody);
    }
  
    @Nullable
    public CqlIdentifier getKeyspace() {
      return keyspace;
    }
  
    @NonNull
    public CqlIdentifier getFunction() {
      return functionName;
    }
  
    public boolean isOrReplace() {
      return orReplace;
    }
  
    public boolean isIfNotExists() {
      return ifNotExists;
    }
  
    @NonNull
    public ImmutableMap<CqlIdentifier, DataType> getParameters() {
      return parameters;
    }
  
    public boolean isReturnsNullOnNull() {
      return returnsNullOnNull;
    }
  
    @Nullable
    public DataType getReturnType() {
      return returnType;
    }
  
    @Nullable
    public String getLanguage() {
      return language;
    }
  
    @Nullable
    public String getFunctionBody() {
      return functionBody;
    }
  }
  