src/com/android/quicksearchbox/CursorBackedSuggestionExtras.kt

/*
 * 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.database.Cursor
import android.util.Log
import kotlin.collections.ArrayList
import kotlin.collections.HashSet
import kotlin.Array

/**
 * SuggestionExtras taking values from the extra columns in a suggestion cursor.
 */
class CursorBackedSuggestionExtras private constructor(
    cursor: Cursor?,
    position: Int,
    extraColumns: List<String>
) : AbstractSuggestionExtras(null) {
    companion object {
        private const val TAG = "QSB.CursorBackedSuggestionExtras"
        private val DEFAULT_COLUMNS: HashSet<String> = HashSet<String>()
        @JvmStatic
        fun createExtrasIfNecessary(cursor: Cursor?, position: Int): CursorBackedSuggestionExtras? {
            val extraColumns: List<String>? =
                CursorBackedSuggestionExtras.Companion.getExtraColumns(cursor)
            return if (extraColumns != null) {
                CursorBackedSuggestionExtras(cursor, position, extraColumns)
            } else {
                null
            }
        }

        @JvmStatic
        fun getCursorColumns(cursor: Cursor?): Array<String>? {
            return try {
                cursor?.getColumnNames()
            } catch (ex: RuntimeException) {
                // all operations on cross-process cursors can throw random exceptions
                Log.e(CursorBackedSuggestionExtras.Companion.TAG, "getColumnNames() failed, ", ex)
                null
            }
        }

        fun cursorContainsExtras(cursor: Cursor?): Boolean {
            val columns: Array<String>? =
                CursorBackedSuggestionExtras.Companion.getCursorColumns(cursor)
            if (columns != null) {
                for (cursorColumn in columns) {
                    if (!CursorBackedSuggestionExtras.Companion.DEFAULT_COLUMNS.contains(cursorColumn)) {
                        return true
                    }
                }
            }
            return false
        }

        @JvmStatic
        fun getExtraColumns(cursor: Cursor?): List<String>? {
            val columns: Array<String> =
                CursorBackedSuggestionExtras.Companion.getCursorColumns(cursor)
                    ?: return null
            var extraColumns: ArrayList<String>? = null
            for (cursorColumn in columns) {
                if (!CursorBackedSuggestionExtras.Companion.DEFAULT_COLUMNS.contains(cursorColumn)) {
                    if (extraColumns == null) {
                        extraColumns = arrayListOf<String>()
                    }
                    extraColumns.add(cursorColumn)
                }
            }
            return extraColumns
        }

        init {
            CursorBackedSuggestionExtras.Companion.DEFAULT_COLUMNS.addAll(
                SuggestionCursorBackedCursor.COLUMNS.asList()
            )
        }
    }

    private val mCursor: Cursor?
    private val mCursorPosition: Int
    private val mExtraColumns: List<String>
    @Override
    override fun doGetExtra(columnName: String?): String? {
        return try {
            mCursor?.moveToPosition(mCursorPosition)
            val columnIdx: Int = mCursor!!.getColumnIndex(columnName)
            if (columnIdx < 0) null else mCursor.getString(columnIdx)
        } catch (ex: RuntimeException) {
            // all operations on cross-process cursors can throw random exceptions
            Log.e(CursorBackedSuggestionExtras.Companion.TAG, "getExtra($columnName) failed, ", ex)
            null
        }
    }

    @Override
    public override fun doGetExtraColumnNames(): List<String> {
        return mExtraColumns
    }

    init {
        mCursor = cursor
        mCursorPosition = position
        mExtraColumns = extraColumns
    }
}