Merge "refactor(MM): Move ComposableMotionValue to mechanics lib (1/2)" into main

/*

 * Copyright (C) 2025 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.mechanics

import androidx.compose.runtime.Composable

import androidx.compose.runtime.LaunchedEffect

import androidx.compose.runtime.SideEffect

import androidx.compose.runtime.remember

import com.android.mechanics.spec.MotionSpec

@Composable

fun rememberMotionValue(

    input: () -> Float,

    spec: () -> MotionSpec,

    gestureContext: GestureContext,

    stableThreshold: Float = 0.01f,

    label: String? = null,

): MotionValue {

    val motionValue =

        remember(input) {

            MotionValue(

                input,

                gestureContext,

                initialSpec = spec(),

                label = label,

                stableThreshold = stableThreshold,

            )

        }

    val currentSpec = spec()

    SideEffect {

        // New spec is intentionally only applied after recomposition.

        motionValue.spec = currentSpec

    }

    LaunchedEffect(motionValue) { motionValue.keepRunning() }

    return motionValue

}

@Composable

fun rememberDerivedMotionValue(

    input: MotionValue,

    spec: () -> MotionSpec,

    stableThreshold: Float = 0.01f,

    label: String? = null,

): MotionValue {

    val motionValue =

        remember(input) {

            MotionValue.createDerived(

                input,

                initialSpec = spec(),

                label = label,

                stableThreshold = stableThreshold,

            )

        }

    val currentSpec = spec()

    SideEffect {

        // New spec is intentionally only applied after recomposition.

        motionValue.spec = currentSpec

    }

    LaunchedEffect(motionValue) { motionValue.keepRunning() }

    return motionValue

}