src/com/android/launcher3/responsive/ResponsiveSpecGroup.kt

/*
 * Copyright (C) 2023 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.launcher3.responsive

import android.content.res.TypedArray
import com.android.launcher3.R
import com.android.launcher3.responsive.ResponsiveSpec.DimensionType

/**
 * Base class for responsive specs that holds a list of width and height specs.
 *
 * @param widthSpecs List of width responsive specifications
 * @param heightSpecs List of height responsive specifications
 */
class ResponsiveSpecGroup<T : IResponsiveSpec>(
    val aspectRatio: Float,
    widthSpecs: List<T>,
    heightSpecs: List<T>
) {
    val widthSpecs: List<T>
    val heightSpecs: List<T>

    init {
        check(aspectRatio > 0f) { "Invalid aspect ratio! Aspect ratio should be bigger than zero." }
        this.widthSpecs = widthSpecs.sortedBy { it.maxAvailableSize }
        this.heightSpecs = heightSpecs.sortedBy { it.maxAvailableSize }
    }

    /**
     * Get a [ResponsiveSpec] within the breakpoint.
     *
     * @param type Type of the spec to be retrieved (width or height)
     * @param availableSize The breakpoint for the spec
     * @return A [ResponsiveSpec].
     */
    fun getSpec(type: DimensionType, availableSize: Int): T {
        val spec =
            if (type == DimensionType.WIDTH) {
                widthSpecs.firstOrNull { availableSize <= it.maxAvailableSize }
            } else {
                heightSpecs.firstOrNull { availableSize <= it.maxAvailableSize }
            }
        check(spec != null) { "No available $type spec found within $availableSize." }
        return spec
    }

    companion object {
        const val XML_GROUP_NAME = "specs"

        fun <T : IResponsiveSpec> create(
            attrs: TypedArray,
            specs: List<T>
        ): ResponsiveSpecGroup<T> {
            val (widthSpecs, heightSpecs) =
                specs.partition { it.dimensionType == DimensionType.WIDTH }
            val aspectRatio = attrs.getFloat(R.styleable.ResponsiveSpecGroup_maxAspectRatio, 0f)
            return ResponsiveSpecGroup(aspectRatio, widthSpecs, heightSpecs)
        }
    }
}