/*
 * Copyright (C) 2022 The Android Open Source Project
 *
 * 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.android.quicksearchbox

import android.text.Spannable

/**
 * Suggestion formatter interface. This is used to bold (or otherwise highlight) portions of a
 * suggestion which were not a part of the query.
 */
abstract class SuggestionFormatter
protected constructor(private val mSpanFactory: TextAppearanceFactory) {
  /**
   * Formats a suggestion for display in the UI.
   *
   * @param query the query as entered by the user
   * @param suggestion the suggestion
   * @return Formatted suggestion text.
   */
  abstract fun formatSuggestion(query: String?, suggestion: String?): CharSequence?
  protected fun applyQueryTextStyle(text: Spannable, start: Int, end: Int) {
    if (start == end) return
    setSpans(text, start, end, mSpanFactory.createSuggestionQueryTextAppearance())
  }

  protected fun applySuggestedTextStyle(text: Spannable, start: Int, end: Int) {
    if (start == end) return
    setSpans(text, start, end, mSpanFactory.createSuggestionSuggestedTextAppearance())
  }

  private fun setSpans(text: Spannable, start: Int, end: Int, spans: Array<Any>) {
    for (span in spans) {
      text.setSpan(span, start, end, 0)
    }
  }
}