/*
 * Copyright 2007 The Closure Compiler Authors.
 *
 * 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 com.google.javascript.jscomp;

import com.google.common.collect.ImmutableSet;


/**
 * Abstract message formatter providing default behavior for implementations
 * of {@link MessageFormatter} needing a {@link SourceExcerptProvider}.
 *
 */
public abstract class AbstractMessageFormatter implements MessageFormatter {
  private final SourceExcerptProvider source;
  private boolean colorize;

  public AbstractMessageFormatter(SourceExcerptProvider source) {
    this.source = source;
  }

  public void setColorize(boolean colorize) {
    this.colorize = colorize;
  }

  /**
   * Get the source excerpt provider.
   */
  protected final SourceExcerptProvider getSource() {
    return source;
  }

  private static final ImmutableSet<String> SUPPORTED_COLOR_TERMINALS =
      ImmutableSet.of("xterm", "xterm-color", "xterm-256color", "screen-bce");

  static boolean termSupportsColor(String term) {
    return SUPPORTED_COLOR_TERMINALS.contains(term);
  }

  private static enum Color {
    ERROR("\u001b[31m"),
    WARNING("\u001b[35m"),
    NO_COLOR("\u001b[39m"),
    BOLD("\u001b[1m"),
    UNBOLD("\u001b[0m");

    private final String controlCharacter;

    Color(String controlCharacter) {
      this.controlCharacter = controlCharacter;
    }

    public String getControlCharacter() {
      return controlCharacter;
    }
  }

  String getLevelName(CheckLevel level) {
    switch (level) {
      case ERROR: return maybeColorize("ERROR", Color.ERROR);
      case WARNING: return maybeColorize("WARNING", Color.WARNING);
      default: return level.toString();
    }
  }

  protected String maybeEmbolden(String text) {
    if (!colorize) {
      return text;
    }
    return Color.BOLD.getControlCharacter() +
        text + Color.UNBOLD.getControlCharacter();
  }

  private String maybeColorize(String text, Color color) {
    if (!colorize) {
      return text;
    }
    return color.getControlCharacter() +
        text + Color.NO_COLOR.getControlCharacter();
  }
}