/*
 * Copyright 2024 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 expo.modules.devmenu.compose.ripple

import androidx.compose.foundation.Indication
import androidx.compose.foundation.IndicationNodeFactory
import androidx.compose.foundation.interaction.Interaction
import androidx.compose.foundation.interaction.InteractionSource
import androidx.compose.foundation.interaction.PressInteraction
import androidx.compose.runtime.Immutable
import androidx.compose.runtime.ProvidableCompositionLocal
import androidx.compose.runtime.Stable
import androidx.compose.runtime.compositionLocalOf
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.graphics.ColorProducer
import androidx.compose.ui.graphics.isSpecified
import androidx.compose.ui.graphics.luminance
import androidx.compose.ui.node.CompositionLocalConsumerModifierNode
import androidx.compose.ui.node.DelegatableNode
import androidx.compose.ui.node.DelegatingNode
import androidx.compose.ui.node.ObserverModifierNode
import androidx.compose.ui.node.currentValueOf
import androidx.compose.ui.node.observeReads
import androidx.compose.ui.unit.Dp
import com.composeunstyled.LocalContentColor
import expo.modules.devmenu.compose.newtheme.LocalIsDarkTheme

/**
 * Creates a Ripple using the provided values and values inferred from the theme.
 *
 * A Ripple is a Material implementation of [Indication] that expresses different [Interaction]s by
 * drawing ripple animations and state layers.
 *
 * A Ripple responds to [PressInteraction.Press] by starting a new animation, and responds to other
 * [Interaction]s by showing a fixed state layer with varying alpha values depending on the
 * [Interaction].
 *
 * [MaterialTheme] provides Ripples using [androidx.compose.foundation.LocalIndication], so a Ripple
 * will be used as the default [Indication] inside components such as
 * [androidx.compose.foundation.clickable] and [androidx.compose.foundation.indication], in addition
 * to Material provided components that use a Ripple as well.
 *
 * You can also explicitly create a Ripple and provide it to custom components in order to change
 * the parameters from the default, such as to create an unbounded ripple with a fixed size.
 *
 * To create a Ripple with a manually defined color that can change over time, see the other
 * [ripple] overload with a [ColorProducer] parameter. This will avoid unnecessary recompositions
 * when changing the color, and preserve existing ripple state when the color changes.
 *
 * @param bounded If true, ripples are clipped by the bounds of the target layout. Unbounded ripples
 *   always animate from the target layout center, bounded ripples animate from the touch position.
 * @param radius the radius for the ripple. If [Dp.Unspecified] is provided then the size will be
 *   calculated based on the target layout size.
 * @param color the color of the ripple. This color is usually the same color used by the text or
 *   iconography in the component. This color will then have [RippleDefaults.rippleAlpha] applied to
 *   calculate the final color used to draw the ripple. If [Color.Unspecified] is provided the color
 *   used will be [RippleDefaults.rippleColor] instead.
 */
@Stable
fun ripple(
  bounded: Boolean = true,
  radius: Dp = Dp.Unspecified,
  color: Color = Color.Unspecified
): IndicationNodeFactory {
  return if (radius == Dp.Unspecified && color == Color.Unspecified) {
    if (bounded) return DefaultBoundedRipple else DefaultUnboundedRipple
  } else {
    RippleNodeFactory(bounded, radius, color)
  }
}

/**
 * Creates a Ripple using the provided values and values inferred from the theme.
 *
 * A Ripple is a Material implementation of [Indication] that expresses different [Interaction]s by
 * drawing ripple animations and state layers.
 *
 * A Ripple responds to [PressInteraction.Press] by starting a new ripple animation, and responds to
 * other [Interaction]s by showing a fixed state layer with varying alpha values depending on the
 * [Interaction].
 *
 * [MaterialTheme] provides Ripples using [androidx.compose.foundation.LocalIndication], so a Ripple
 * will be used as the default [Indication] inside components such as
 * [androidx.compose.foundation.clickable] and [androidx.compose.foundation.indication], in addition
 * to Material provided components that use a Ripple as well.
 *
 * You can also explicitly create a Ripple and provide it to custom components in order to change
 * the parameters from the default, such as to create an unbounded ripple with a fixed size.
 *
 * To create a Ripple with a static color, see the [ripple] overload with a [Color] parameter. This
 * overload is optimized for Ripples that have dynamic colors that change over time, to reduce
 * unnecessary recompositions.
 *
 * @param color the color of the ripple. This color is usually the same color used by the text or
 *   iconography in the component. This color will then have [RippleDefaults.rippleAlpha] applied to
 *   calculate the final color used to draw the ripple. If you are creating this [ColorProducer]
 *   outside of composition (where it will be automatically remembered), make sure that its instance
 *   is stable (such as by remembering the object that holds it), or remember the returned [ripple]
 *   object to make sure that ripple nodes are not being created each recomposition.
 * @param bounded If true, ripples are clipped by the bounds of the target layout. Unbounded ripples
 *   always animate from the target layout center, bounded ripples animate from the touch position.
 * @param radius the radius for the ripple. If [Dp.Unspecified] is provided then the size will be
 *   calculated based on the target layout size.
 */
@Stable
fun ripple(
  color: ColorProducer,
  bounded: Boolean = true,
  radius: Dp = Dp.Unspecified
): IndicationNodeFactory {
  return RippleNodeFactory(bounded, radius, color)
}

/** Default values used by [ripple]. */
object RippleDefaults {
  /**
   * Represents the default color that will be used for a ripple if a color has not been
   * explicitly set on the ripple instance.
   *
   * @param contentColor the color of content (text or iconography) in the component that contains
   *   the ripple.
   * @param lightTheme whether the theme is light or not
   */
  fun rippleColor(contentColor: Color, lightTheme: Boolean): Color {
    val contentLuminance = contentColor.luminance()
    // If we are on a colored surface (typically indicated by low luminance content), the
    // ripple color should be white.
    return if (!lightTheme && contentLuminance < 0.5) {
      Color.White
      // Otherwise use contentColor
    } else {
      contentColor
    }
  }

  /**
   * Represents the default [RippleAlpha] that will be used for a ripple to indicate different
   * states.
   *
   * @param contentColor the color of content (text or iconography) in the component that contains
   *   the ripple.
   * @param lightTheme whether the theme is light or not
   */
  fun rippleAlpha(contentColor: Color, lightTheme: Boolean): RippleAlpha {
    return when {
      lightTheme -> {
        if (contentColor.luminance() > 0.5) {
          LightThemeHighContrastRippleAlpha
        } else {
          LightThemeLowContrastRippleAlpha
        }
      }

      else -> {
        DarkThemeRippleAlpha
      }
    }
  }
}

/**
 * CompositionLocal used for providing [RippleConfiguration] down the tree. This acts as a
 * tree-local 'override' for ripples used inside components that you cannot directly control, such
 * as to change the color of a specific component's ripple, or disable it entirely by providing
 * `null`.
 *
 * In most cases you should rely on the default theme behavior for consistency with other components
 * - this exists as an escape hatch for individual components and is not intended to be used for
 *   full theme customization across an application. For this use case you should instead build your
 *   own custom ripple that queries your design system theme values directly using
 *   [createRippleModifierNode].
 */
val LocalRippleConfiguration: ProvidableCompositionLocal<RippleConfiguration?> =
  compositionLocalOf {
    RippleConfiguration()
  }

/**
 * Configuration for [ripple] appearance, provided using [LocalRippleConfiguration]. In most cases
 * the default values should be used, for custom design system use cases you should instead build
 * your own custom ripple using [createRippleModifierNode]. To disable the ripple, provide `null`
 * using [LocalRippleConfiguration].
 *
 * @param color the color override for the ripple. If [Color.Unspecified], then the default color
 *   from the theme will be used instead. Note that if the ripple has a color explicitly set with
 *   the parameter on [ripple], that will always be used instead of this value.
 * @param rippleAlpha the [RippleAlpha] override for this ripple. If null, then the default alpha
 *   will be used instead.
 */
@Immutable
class RippleConfiguration(
  val color: Color = Color.Unspecified,
  val rippleAlpha: RippleAlpha? = null
) {
  override fun equals(other: Any?): Boolean {
    if (this === other) return true
    if (other !is RippleConfiguration) return false

    if (color != other.color) return false
    if (rippleAlpha != other.rippleAlpha) return false

    return true
  }

  override fun hashCode(): Int {
    var result = color.hashCode()
    result = 31 * result + (rippleAlpha?.hashCode() ?: 0)
    return result
  }

  override fun toString(): String {
    return "RippleConfiguration(color=$color, rippleAlpha=$rippleAlpha)"
  }
}

@Stable
private class RippleNodeFactory
private constructor(
  private val bounded: Boolean,
  private val radius: Dp,
  private val colorProducer: ColorProducer?,
  private val color: Color
) : IndicationNodeFactory {
  constructor(
    bounded: Boolean,
    radius: Dp,
    colorProducer: ColorProducer
  ) : this(bounded, radius, colorProducer, Color.Unspecified)

  constructor(bounded: Boolean, radius: Dp, color: Color) : this(bounded, radius, null, color)

  override fun create(interactionSource: InteractionSource): DelegatableNode {
    val colorProducer = colorProducer ?: ColorProducer { color }
    return DelegatingThemeAwareRippleNode(interactionSource, bounded, radius, colorProducer)
  }

  override fun equals(other: Any?): Boolean {
    if (this === other) return true
    if (other !is RippleNodeFactory) return false

    if (bounded != other.bounded) return false
    if (radius != other.radius) return false
    if (colorProducer != other.colorProducer) return false
    return color == other.color
  }

  override fun hashCode(): Int {
    var result = bounded.hashCode()
    result = 31 * result + radius.hashCode()
    result = 31 * result + colorProducer.hashCode()
    result = 31 * result + color.hashCode()
    return result
  }
}

private class DelegatingThemeAwareRippleNode(
  private val interactionSource: InteractionSource,
  private val bounded: Boolean,
  private val radius: Dp,
  private val color: ColorProducer
) : DelegatingNode(), CompositionLocalConsumerModifierNode, ObserverModifierNode {
  private var rippleNode: DelegatableNode? = null

  override fun onAttach() {
    updateConfiguration()
  }

  override fun onObservedReadsChanged() {
    updateConfiguration()
  }

  /**
   * Handles [LocalRippleConfiguration] changing between null / non-null. Changes to
   * [RippleConfiguration.color] and [RippleConfiguration.rippleAlpha] are handled as part of the
   * ripple definition.
   */
  private fun updateConfiguration() {
    observeReads {
      val configuration = currentValueOf(LocalRippleConfiguration)
      if (configuration == null) {
        removeRipple()
      } else {
        if (rippleNode == null) attachNewRipple()
      }
    }
  }

  private fun attachNewRipple() {
    val calculateColor = ColorProducer {
      val userDefinedColor = color()
      if (userDefinedColor.isSpecified) {
        userDefinedColor
      } else {
        // If this is null, the ripple will be removed, so this should always be non-null in
        // normal use
        val rippleConfiguration = currentValueOf(LocalRippleConfiguration)
        if (rippleConfiguration?.color?.isSpecified == true) {
          rippleConfiguration.color
        } else {
          RippleDefaults.rippleColor(
            contentColor = currentValueOf(LocalContentColor),
            lightTheme = !currentValueOf(LocalIsDarkTheme)
          )
        }
      }
    }
    val calculateRippleAlpha = {
      // If this is null, the ripple will be removed, so this should always be non-null in
      // normal use
      val rippleConfiguration = currentValueOf(LocalRippleConfiguration)
      rippleConfiguration?.rippleAlpha
        ?: RippleDefaults.rippleAlpha(
          contentColor = currentValueOf(LocalContentColor),
          lightTheme = !currentValueOf(LocalIsDarkTheme)
        )
    }

    rippleNode =
      delegate(
        createRippleModifierNode(
          interactionSource,
          bounded,
          radius,
          calculateColor,
          calculateRippleAlpha
        )
      )
  }

  private fun removeRipple() {
    rippleNode?.let { undelegate(it) }
    rippleNode = null
  }
}

private val DefaultBoundedRipple =
  RippleNodeFactory(bounded = true, radius = Dp.Unspecified, color = Color.Unspecified)

private val DefaultUnboundedRipple =
  RippleNodeFactory(bounded = false, radius = Dp.Unspecified, color = Color.Unspecified)

/**
 * Alpha values for high luminance content in a light theme.
 *
 * This content will typically be placed on colored surfaces, so it is important that the contrast
 * here is higher to meet accessibility standards, and increase legibility.
 *
 * These levels are typically used for text / iconography in primary colored tabs / bottom
 * navigation / etc.
 */
private val LightThemeHighContrastRippleAlpha =
  RippleAlpha(
    pressedAlpha = 0.24f,
    focusedAlpha = 0.24f,
    draggedAlpha = 0.16f,
    hoveredAlpha = 0.08f
  )

/**
 * Alpha levels for low luminance content in a light theme.
 *
 * This content will typically be placed on grayscale surfaces, so the contrast here can be lower
 * without sacrificing accessibility and legibility.
 *
 * These levels are typically used for body text on the main surface (white in light theme, grey in
 * dark theme) and text / iconography in surface colored tabs / bottom navigation / etc.
 */
private val LightThemeLowContrastRippleAlpha =
  RippleAlpha(
    pressedAlpha = 0.12f,
    focusedAlpha = 0.12f,
    draggedAlpha = 0.08f,
    hoveredAlpha = 0.04f
  )

/** Alpha levels for all content in a dark theme. */
private val DarkThemeRippleAlpha =
  RippleAlpha(
    pressedAlpha = 0.10f,
    focusedAlpha = 0.12f,
    draggedAlpha = 0.08f,
    hoveredAlpha = 0.04f
  )