/**
    * 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.hadoop.hbase.hbtop.screen.field;
  
  import java.util.EnumMap;
  import java.util.List;
  
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.hbtop.field.Field;
  import org.apache.hadoop.hbase.hbtop.screen.AbstractScreenView;
  import org.apache.hadoop.hbase.hbtop.screen.Screen;
  import org.apache.hadoop.hbase.hbtop.screen.ScreenView;
  import org.apache.hadoop.hbase.hbtop.terminal.KeyPress;
  import org.apache.hadoop.hbase.hbtop.terminal.Terminal;
  import org.apache.hadoop.hbase.hbtop.terminal.TerminalPrinter;
  
  /**
   * The screen where we can change the displayed fields, the sort key and the order of the fields.
   */
  @InterfaceAudience.Private
  public class FieldScreenView extends AbstractScreenView {
  
    private static final int SCREEN_DESCRIPTION_START_ROW = 0;
    private static final int FIELD_START_ROW = 5;
  
    private final FieldScreenPresenter fieldScreenPresenter;
  
    public FieldScreenView(Screen screen, Terminal terminal, Field sortField, List<Field> fields,
      EnumMap<Field, Boolean> fieldDisplayMap, FieldScreenPresenter.ResultListener resultListener,
      ScreenView nextScreenView) {
      super(screen, terminal);
      this.fieldScreenPresenter = new FieldScreenPresenter(this, sortField, fields, fieldDisplayMap,
        resultListener, nextScreenView);
    }
  
    @Override
    public void init() {
      fieldScreenPresenter.init();
    }
  
    @Override
    public ScreenView handleKeyPress(KeyPress keyPress) {
      switch (keyPress.getType()) {
        case Escape:
          return fieldScreenPresenter.transitionToNextScreen();
  
        case ArrowUp:
          fieldScreenPresenter.arrowUp();
          return this;
  
        case ArrowDown:
          fieldScreenPresenter.arrowDown();
          return this;
  
        case PageUp:
        case Home:
          fieldScreenPresenter.pageUp();
          return this;
  
        case PageDown:
        case End:
          fieldScreenPresenter.pageDown();
          return this;
  
        case ArrowRight:
          fieldScreenPresenter.turnOnMoveMode();
          return this;
  
        case ArrowLeft:
        case Enter:
          fieldScreenPresenter.turnOffMoveMode();
          return this;
  
        default:
          // Do nothing
          break;
      }
  
      if (keyPress.getType() != KeyPress.Type.Character) {
        return this;
      }
  
      assert keyPress.getCharacter() != null;
      switch (keyPress.getCharacter()) {
       case 'd':
       case ' ':
         fieldScreenPresenter.switchFieldDisplay();
         break;
 
       case 's':
         fieldScreenPresenter.setSortField();
         break;
 
       case 'q':
         return fieldScreenPresenter.transitionToNextScreen();
 
       default:
         // Do nothing
         break;
     }
 
     return this;
   }
 
   public void showFieldScreen(String sortFieldHeader, List<Field> fields,
     EnumMap<Field, Boolean> fieldDisplayMap, int currentPosition, int headerMaxLength,
     int descriptionMaxLength, boolean moveMode) {
     showScreenDescription(sortFieldHeader);
 
     for (int i = 0; i < fields.size(); i ++) {
       Field field = fields.get(i);
       showField(i, field, fieldDisplayMap.get(field), i == currentPosition, headerMaxLength,
         descriptionMaxLength, moveMode);
     }
   }
 
   public void showScreenDescription(String sortKeyHeader) {
     TerminalPrinter printer = getTerminalPrinter(SCREEN_DESCRIPTION_START_ROW);
     printer.startBold().print("Fields Management").stopBold().endOfLine();
     printer.print("Current Sort Field: ").startBold().print(sortKeyHeader).stopBold().endOfLine();
     printer.print("Navigate with up/down, Right selects for move then <Enter> or Left commits,")
       .endOfLine();
     printer.print("'d' or <Space> toggles display, 's' sets sort. Use 'q' or <Esc> to end!")
       .endOfLine();
   }
 
   public void showField(int pos, Field field, boolean display, boolean selected,
     int fieldHeaderMaxLength, int fieldDescriptionMaxLength, boolean moveMode) {
 
     String fieldHeader = String.format("%-" + fieldHeaderMaxLength + "s", field.getHeader());
     String fieldDescription = String.format("%-" + fieldDescriptionMaxLength + "s",
       field.getDescription());
 
     int row = FIELD_START_ROW + pos;
     TerminalPrinter printer = getTerminalPrinter(row);
     if (selected) {
       String prefix = display ? "* " : "  ";
       if (moveMode) {
         printer.print(prefix);
 
         if (display) {
           printer.startBold();
         }
 
         printer.startHighlight()
           .printFormat("%s = %s", fieldHeader, fieldDescription).stopHighlight();
 
         if (display) {
           printer.stopBold();
         }
 
         printer.endOfLine();
       } else {
         printer.print(prefix);
 
         if (display) {
           printer.startBold();
         }
 
         printer.startHighlight().print(fieldHeader).stopHighlight()
           .printFormat(" = %s", fieldDescription);
 
         if (display) {
           printer.stopBold();
         }
 
         printer.endOfLine();
       }
     } else {
       if (display) {
         printer.print("* ").startBold().printFormat("%s = %s", fieldHeader, fieldDescription)
           .stopBold().endOfLine();
       } else {
         printer.printFormat("  %s = %s", fieldHeader, fieldDescription).endOfLine();
       }
     }
   }
 }