/*
 * 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.datasketches.theta;

import static java.nio.charset.StandardCharsets.UTF_8;
import static org.apache.datasketches.theta.PreambleUtil.PREAMBLE_LONGS_BYTE;
import static org.apache.datasketches.theta.PreambleUtil.SER_VER_BYTE;
import static org.apache.datasketches.theta.PreambleUtil.insertLgArrLongs;
import static org.apache.datasketches.theta.PreambleUtil.insertLgNomLongs;
import static org.apache.datasketches.theta.PreambleUtil.insertLgResizeFactor;
import static org.apache.datasketches.theta.UpdateSketch.isResizeFactorIncorrect;
import static org.testng.Assert.assertEquals;
import static org.testng.Assert.assertTrue;
import static org.testng.Assert.fail;

import java.nio.ByteBuffer;

import org.apache.datasketches.common.Family;
import org.apache.datasketches.common.ResizeFactor;
import org.apache.datasketches.common.SketchesArgumentException;
import org.apache.datasketches.memory.DefaultMemoryRequestServer;
import org.apache.datasketches.memory.MemoryRequestServer;
import org.apache.datasketches.memory.WritableMemory;
import org.apache.datasketches.thetacommon.ThetaUtil;
import org.testng.annotations.Test;

/**
 * @author Lee Rhodes
 */
public class UpdateSketchTest {

  @Test
  public void checkOtherUpdates() {
    int k = 512;
    UpdateSketch sk1 = UpdateSketch.builder().setNominalEntries(k).build();
    sk1.update(1L);   //#1 long
    sk1.update(1.5);  //#2 double
    sk1.update(0.0);
    sk1.update(-0.0); //#3 double
    String s = null;
    sk1.update(s);    //null string
    s = "";
    sk1.update(s);    //empty string
    s = "String";
    sk1.update(s);    //#4 actual string

    byte[] byteArr = null;
    sk1.update(byteArr); //null byte[]
    byteArr = new byte[0];
    sk1.update(byteArr); //empty byte[]
    sk1.update(ByteBuffer.wrap(byteArr)); // empty byte[]
    byteArr = "Byte Array".getBytes(UTF_8);
    sk1.update(byteArr); //#5 actual byte[]
    sk1.update(ByteBuffer.wrap(byteArr, 0, 10));  // whole byte array
    sk1.update(ByteBuffer.wrap(byteArr, 2, 6));   // #6 byte array slice

    char[] charArr = null;
    sk1.update(charArr); //null char[]
    charArr = new char[0];
    sk1.update(charArr); //empty char[]
    charArr = "String".toCharArray();
    sk1.update(charArr); //#7 actual char[]

    int[] intArr = null;
    sk1.update(intArr); //null int[]
    intArr = new int[0];
    sk1.update(intArr); //empty int[]
    int[] intArr2 = { 1, 2, 3, 4, 5 };
    sk1.update(intArr2); //#8 actual int[]

    long[] longArr = null;
    sk1.update(longArr); //null long[]
    longArr = new long[0];
    sk1.update(longArr); //empty long[]
    long[] longArr2 = { 6, 7, 8, 9 };
    sk1.update(longArr2); //#9 actual long[]

    double est = sk1.getEstimate();
    assertEquals(est, 9.0, 0.0);
  }

  @Test
  public void checkStartingSubMultiple() {
    int lgSubMul;
    lgSubMul = ThetaUtil.startingSubMultiple(10, ResizeFactor.X1.lg(), 5);
    assertEquals(lgSubMul, 10);
    lgSubMul = ThetaUtil.startingSubMultiple(10, ResizeFactor.X2.lg(), 5);
    assertEquals(lgSubMul, 5);
    lgSubMul = ThetaUtil.startingSubMultiple(10, ResizeFactor.X4.lg(), 5);
    assertEquals(lgSubMul, 6);
    lgSubMul = ThetaUtil.startingSubMultiple(10, ResizeFactor.X8.lg(), 5);
    assertEquals(lgSubMul, 7);
    lgSubMul = ThetaUtil.startingSubMultiple(4, ResizeFactor.X1.lg(), 5);
    assertEquals(lgSubMul, 5);
  }

  @Test
  public void checkBuilder() {
    UpdateSketchBuilder bldr = UpdateSketch.builder();

    long seed = 12345L;
    bldr.setSeed(seed);
    assertEquals(bldr.getSeed(), seed);

    float p = (float)0.5;
    bldr.setP(p);
    assertEquals(bldr.getP(), p);

    ResizeFactor rf = ResizeFactor.X4;
    bldr.setResizeFactor(rf);
    assertEquals(bldr.getResizeFactor(), rf);

    Family fam = Family.ALPHA;
    bldr.setFamily(fam);
    assertEquals(bldr.getFamily(), fam);

    int lgK = 10;
    int k = 1 << lgK;
    bldr.setNominalEntries(k);
    assertEquals(bldr.getLgNominalEntries(), lgK);

    MemoryRequestServer mrs = new DefaultMemoryRequestServer();
    bldr.setMemoryRequestServer(mrs);
    assertEquals(bldr.getMemoryRequestServer(), mrs);

    println(bldr.toString());
  }

  @Test(expectedExceptions = SketchesArgumentException.class)
  public void checkBuilderNomEntries() {
    UpdateSketchBuilder bldr = UpdateSketch.builder();
    int k = 1 << 27;
    bldr.setNominalEntries(k);
  }

  @Test
  public void checkCompact() {
    UpdateSketch sk = Sketches.updateSketchBuilder().build();
    CompactSketch csk = sk.compact();
    assertEquals(csk.getCompactBytes(), 8);
  }

  @Test(expectedExceptions = SketchesArgumentException.class)
  public void checkIncompatibleFamily() {
    UpdateSketch sk = Sketches.updateSketchBuilder().build();
    sk.update(1);
    WritableMemory wmem = WritableMemory.writableWrap(sk.compact().toByteArray());
    UpdateSketch.wrap(wmem, ThetaUtil.DEFAULT_UPDATE_SEED);
  }

  @Test
  public void checkCorruption() {
    UpdateSketch sk = Sketches.updateSketchBuilder().build();
    sk.update(1);
    WritableMemory wmem = WritableMemory.writableWrap(sk.toByteArray());
    try {
      wmem.putByte(SER_VER_BYTE, (byte) 2);
      UpdateSketch.wrap(wmem, ThetaUtil.DEFAULT_UPDATE_SEED);
      fail();
    } catch (SketchesArgumentException e) { }
    try {
      wmem.putByte(SER_VER_BYTE, (byte) 3);
      wmem.putByte(PREAMBLE_LONGS_BYTE, (byte) 2);
      UpdateSketch.wrap(wmem, ThetaUtil.DEFAULT_UPDATE_SEED);
      fail();
    } catch (SketchesArgumentException e) { }
  }

  @Test
  public void checkIsResizeFactorIncorrect() {
    WritableMemory wmem = WritableMemory.allocate(8);
    insertLgNomLongs(wmem, 26);
    for (int lgK = 4; lgK <= 26; lgK++) {
      insertLgNomLongs(wmem, lgK);
      int lgT = lgK + 1;
      for (int lgA = 5; lgA <= lgT; lgA++) {
        insertLgArrLongs(wmem, lgA);
        for (int lgR = 0; lgR <= 3; lgR++) {
          insertLgResizeFactor(wmem, lgR);
          boolean lgRbad = isResizeFactorIncorrect(wmem, lgK, lgA);
          boolean rf123 = (lgR > 0) && !(((lgT - lgA) % lgR) == 0);
          boolean rf0 = (lgR == 0) && (lgA != lgT);
          assertTrue((lgRbad == rf0) || (lgRbad == rf123));
        }
      }
    }
  }


  @SuppressWarnings("unused")
  @Test
  public void checkCompactOpsMemoryToCompact() {
    WritableMemory skwmem, cskwmem1, cskwmem2, cskwmem3;
    CompactSketch csk1, csk2, csk3;
    int lgK = 6;
    UpdateSketch sk = Sketches.updateSketchBuilder().setLogNominalEntries(lgK).build();
    int n = 1 << (lgK + 1);
    for (int i = 2; i < n; i++) { sk.update(i); }
    int cbytes = sk.getCompactBytes();
    byte[] byteArr = sk.toByteArray();
    skwmem = WritableMemory.writableWrap(byteArr);
    cskwmem1 = WritableMemory.allocate(cbytes);
    cskwmem2 = WritableMemory.allocate(cbytes);
    cskwmem3 = WritableMemory.allocate(cbytes);
    csk1 = sk.compact(true, cskwmem1);
    csk2 = CompactOperations.memoryToCompact(skwmem, true, cskwmem2);
    csk3 = CompactOperations.memoryToCompact(cskwmem1, true, cskwmem3);
    assertTrue(cskwmem1.equalTo(cskwmem2));
    assertTrue(cskwmem1.equalTo(cskwmem3));
  }

  @Test
  public void printlnTest() {
    println("PRINTING: "+this.getClass().getName());
  }

  /**
   * @param s value to print
   */
  static void println(String s) {
    //System.out.println(s); //disable here
  }
}
