/*
 * 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 org.apache.phoenix.schema.types;

import java.sql.SQLException;
import java.sql.Types;
import java.text.Format;
import java.util.Arrays;
import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.phoenix.exception.DataExceedsCapacityException;
import org.apache.phoenix.schema.SortOrder;
import org.apache.phoenix.util.ByteUtil;
import org.apache.phoenix.util.StringUtil;

import org.apache.phoenix.thirdparty.com.google.common.base.Strings;

/**
 * Fixed length single byte characters
 */
public class PChar extends PDataType<String> {

  public static final PChar INSTANCE = new PChar();

  private PChar() {
    super("CHAR", Types.CHAR, String.class, null, 1);
  }

  @Override
  public void pad(ImmutableBytesWritable ptr, Integer maxLength, SortOrder sortOrder) {
    if (ptr.getLength() >= maxLength) {
      return;
    }
    byte[] newBytes = new byte[maxLength];
    System.arraycopy(ptr.get(), ptr.getOffset(), newBytes, 0, ptr.getLength());
    Arrays.fill(newBytes, ptr.getLength(), maxLength,
      sortOrder == SortOrder.ASC ? StringUtil.SPACE_UTF8 : StringUtil.INVERTED_SPACE_UTF8);
    ptr.set(newBytes);
  }

  @Override
  public byte[] pad(byte[] b, Integer maxLength, SortOrder sortOrder) {
    if (b == null || b.length >= maxLength) {
      return b;
    }
    byte[] newBytes = new byte[maxLength];
    System.arraycopy(b, 0, newBytes, 0, b.length);
    Arrays.fill(newBytes, b.length, maxLength,
      sortOrder == SortOrder.ASC ? StringUtil.SPACE_UTF8 : StringUtil.INVERTED_SPACE_UTF8);
    return newBytes;
  }

  @Override
  public Object pad(Object object, Integer maxLength) {
    String s = (String) object;
    if (s == null) {
      return Strings.padEnd("", maxLength, ' ');
    }
    if (s.length() == maxLength) {
      return object;
    }
    if (s.length() > maxLength) {
      throw new DataExceedsCapacityException(this, maxLength, null, null);
    }
    return Strings.padEnd(s, maxLength, ' ');
  }

  @Override
  public byte[] toBytes(Object object) {
    if (object == null) {
      return ByteUtil.EMPTY_BYTE_ARRAY;
    }
    byte[] b = PVarchar.INSTANCE.toBytes(object);
    if (b.length != ((String) object).length()) {
      throw newIllegalDataException("CHAR types may only contain single byte characters.");
    }
    return b;
  }

  @Override
  public int toBytes(Object object, byte[] bytes, int offset) {
    if (object == null) {
      throw newIllegalDataException(this + " may not be null");
    }
    int len = PVarchar.INSTANCE.toBytes(object, bytes, offset);
    if (len != ((String) object).length()) {
      throw newIllegalDataException("CHAR types may only contain single byte characters.");
    }
    return len;
  }

  @Override
  public Object toObject(byte[] bytes, int offset, int length, PDataType actualType,
    SortOrder sortOrder, Integer maxLength, Integer scale) {
    if (length == 0) {
      return null;
    }
    if (!actualType.isCoercibleTo(this)) {
      throwConstraintViolationException(actualType, this);
    }
    length = StringUtil.getUnpaddedCharLength(bytes, offset, length, sortOrder);
    if (sortOrder == SortOrder.DESC) {
      bytes = SortOrder.invert(bytes, offset, length);
      offset = 0;
    }
    // TODO: UTF-8 decoder that will invert as it decodes
    String s = Bytes.toString(bytes, offset, length);
    if (length != s.length()) {
      throw newIllegalDataException("CHAR types may only contain single byte characters.");
    }
    return s;
  }

  @Override
  public Object toObject(byte[] bytes, int offset, int length, PDataType actualType,
    SortOrder sortOrder, Integer maxLength, Integer scale, Class jdbcType) throws SQLException {
    if (String.class.isAssignableFrom(jdbcType)) {
      // We don't actually get here, we shortcut the String case in ResultSet
      return toObject(bytes, offset, length, actualType, sortOrder, maxLength, scale);
    }
    throw newMismatchException(actualType, jdbcType);
  }

  @Override
  public Object toObject(Object object, PDataType actualType) {
    if (equalsAny(actualType, PVarchar.INSTANCE, this)) {
      String s = (String) object;
      return s == null || s.length() > 0 ? s : null;
    }
    return throwConstraintViolationException(actualType, this);
  }

  @Override
  public boolean isCoercibleTo(PDataType targetType) {
    return equalsAny(targetType, this, PVarchar.INSTANCE, PBinary.INSTANCE, PVarbinary.INSTANCE);
  }

  @Override
  public void coerceBytes(ImmutableBytesWritable ptr, Object o, PDataType actualType,
    Integer actualMaxLength, Integer actualScale, SortOrder actualModifier,
    Integer desiredMaxLength, Integer desiredScale, SortOrder expectedModifier) {
    if (
      o != null && actualType.equals(PVarchar.INSTANCE) && ((String) o).length() != ptr.getLength()
    ) {
      throw newIllegalDataException("CHAR types may only contain single byte characters.");
    }
    super.coerceBytes(ptr, o, actualType, actualMaxLength, actualScale, actualModifier,
      desiredMaxLength, desiredScale, expectedModifier);
    if (ptr.getLength() > 0 && desiredMaxLength != null && desiredMaxLength > ptr.getLength()) {
      pad(ptr, desiredMaxLength, expectedModifier);
    }
  }

  @Override
  public boolean isSizeCompatible(ImmutableBytesWritable ptr, Object value, PDataType srcType,
    SortOrder sortOrder, Integer maxLength, Integer scale, Integer desiredMaxLength,
    Integer desiredScale) {
    if (ptr.getLength() != 0 && desiredMaxLength != null) {
      if (maxLength == null) {
        if (value != null && srcType == INSTANCE) { // Use value if provided
          maxLength = ((String) value).length();
        } else {
          this.coerceBytes(ptr, value, srcType, maxLength, scale, sortOrder, desiredMaxLength,
            desiredScale, sortOrder, true);
          maxLength = ptr.getLength(); // Only single byte characters
        }
      }
      return maxLength <= desiredMaxLength;
    }
    return true;
  }

  @Override
  public boolean isFixedWidth() {
    return true;
  }

  @Override
  public Integer getByteSize() {
    return null;
  }

  @Override
  public Integer getMaxLength(Object o) {
    if (o == null) {
      return null;
    }
    String value = (String) o;
    return value.length();
  }

  @Override
  public int estimateByteSize(Object o) {
    String value = (String) o;
    return value.length();
  }

  @Override
  public int compareTo(Object lhs, Object rhs, PDataType rhsType) {
    return PVarchar.INSTANCE.compareTo(lhs, rhs, rhsType);
  }

  @Override
  public Object toObject(String value) {
    if (StringUtil.hasMultiByteChars(value)) {
      throw newIllegalDataException("CHAR types may only contain single byte characters.");
    }
    return value;
  }

  @Override
  public Integer estimateByteSizeFromLength(Integer length) {
    return length;
  }

  @Override
  public boolean isBytesComparableWith(PDataType otherType) {
    return super.isBytesComparableWith(otherType) || otherType.equals(PVarchar.INSTANCE);
  }

  @Override
  public String toStringLiteral(byte[] b, int offset, int length, Format formatter) {
    return PVarchar.INSTANCE.toStringLiteral(b, offset, length, formatter);
  }

  @Override
  public String toStringLiteral(Object o, Format formatter) {
    return PVarchar.INSTANCE.toStringLiteral(o, formatter);
  }

  @Override
  public Object getSampleValue(Integer maxLength, Integer arrayLength) {
    return PVarchar.INSTANCE.getSampleValue(maxLength, arrayLength);
  }

}
