mihon/app/src/main/java/eu/kanade/presentation/components/Button.kt

package eu.kanade.presentation.components

import androidx.compose.animation.core.Animatable
import androidx.compose.animation.core.VectorConverter
import androidx.compose.foundation.BorderStroke
import androidx.compose.foundation.interaction.FocusInteraction
import androidx.compose.foundation.interaction.HoverInteraction
import androidx.compose.foundation.interaction.Interaction
import androidx.compose.foundation.interaction.InteractionSource
import androidx.compose.foundation.interaction.MutableInteractionSource
import androidx.compose.foundation.interaction.PressInteraction
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.PaddingValues
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.RowScope
import androidx.compose.foundation.layout.defaultMinSize
import androidx.compose.foundation.layout.padding
import androidx.compose.material3.Button
import androidx.compose.material3.ColorScheme
import androidx.compose.material3.ElevatedButton
import androidx.compose.material3.LocalContentColor
import androidx.compose.material3.MaterialTheme
import androidx.compose.material3.ProvideTextStyle
import androidx.compose.material3.TextButton
import androidx.compose.runtime.Composable
import androidx.compose.runtime.CompositionLocalProvider
import androidx.compose.runtime.Immutable
import androidx.compose.runtime.LaunchedEffect
import androidx.compose.runtime.Stable
import androidx.compose.runtime.State
import androidx.compose.runtime.mutableStateListOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.rememberUpdatedState
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.geometry.Offset
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.graphics.Shape
import androidx.compose.ui.unit.Dp
import androidx.compose.ui.unit.dp
import eu.kanade.presentation.util.animateElevation
import androidx.compose.material3.ButtonDefaults as M3ButtonDefaults

/**
 * TextButton with additional onLongClick functionality.
 *
 * @see androidx.compose.material3.TextButton
 */
@Composable
fun TextButton(
    onClick: () -> Unit,
    modifier: Modifier = Modifier,
    onLongClick: (() -> Unit)? = null,
    enabled: Boolean = true,
    interactionSource: MutableInteractionSource = remember { MutableInteractionSource() },
    elevation: ButtonElevation? = null,
    shape: Shape = M3ButtonDefaults.textShape,
    border: BorderStroke? = null,
    colors: ButtonColors = ButtonColors(
        containerColor = Color.Transparent,
        contentColor = MaterialTheme.colorScheme.primary,
        disabledContainerColor = Color.Transparent,
        disabledContentColor = MaterialTheme.colorScheme.onSurface.copy(alpha = 0.38f),
    ),
    contentPadding: PaddingValues = M3ButtonDefaults.TextButtonContentPadding,
    content: @Composable RowScope.() -> Unit,
) =
    Button(
        onClick = onClick,
        modifier = modifier,
        onLongClick = onLongClick,
        enabled = enabled,
        interactionSource = interactionSource,
        elevation = elevation,
        shape = shape,
        border = border,
        colors = colors,
        contentPadding = contentPadding,
        content = content,
    )

/**
 * Button with additional onLongClick functionality.
 *
 * @see androidx.compose.material3.TextButton
 */
@Composable
fun Button(
    onClick: () -> Unit,
    modifier: Modifier = Modifier,
    onLongClick: (() -> Unit)? = null,
    enabled: Boolean = true,
    interactionSource: MutableInteractionSource = remember { MutableInteractionSource() },
    elevation: ButtonElevation? = ButtonDefaults.buttonElevation(),
    shape: Shape = M3ButtonDefaults.textShape,
    border: BorderStroke? = null,
    colors: ButtonColors = ButtonDefaults.buttonColors(),
    contentPadding: PaddingValues = M3ButtonDefaults.ContentPadding,
    content: @Composable RowScope.() -> Unit,
) {
    val containerColor = colors.containerColor(enabled).value
    val contentColor = colors.contentColor(enabled).value
    val shadowElevation = elevation?.shadowElevation(enabled, interactionSource)?.value ?: 0.dp
    val tonalElevation = elevation?.tonalElevation(enabled, interactionSource)?.value ?: 0.dp

    Surface(
        onClick = onClick,
        modifier = modifier,
        onLongClick = onLongClick,
        shape = shape,
        color = containerColor,
        contentColor = contentColor,
        tonalElevation = tonalElevation,
        shadowElevation = shadowElevation,
        border = border,
        interactionSource = interactionSource,
        enabled = enabled,
    ) {
        CompositionLocalProvider(LocalContentColor provides contentColor) {
            ProvideTextStyle(value = MaterialTheme.typography.labelLarge) {
                Row(
                    Modifier.defaultMinSize(
                        minWidth = M3ButtonDefaults.MinWidth,
                        minHeight = M3ButtonDefaults.MinHeight,
                    )
                        .padding(contentPadding),
                    horizontalArrangement = Arrangement.Center,
                    verticalAlignment = Alignment.CenterVertically,
                    content = content,
                )
            }
        }
    }
}

object ButtonDefaults {
    /**
     * Creates a [ButtonColors] that represents the default container and content colors used in a
     * [Button].
     *
     * @param containerColor the container color of this [Button] when enabled.
     * @param contentColor the content color of this [Button] when enabled.
     * @param disabledContainerColor the container color of this [Button] when not enabled.
     * @param disabledContentColor the content color of this [Button] when not enabled.
     */
    @Composable
    fun buttonColors(
        containerColor: Color = MaterialTheme.colorScheme.primary,
        contentColor: Color = MaterialTheme.colorScheme.onPrimary,
        disabledContainerColor: Color = MaterialTheme.colorScheme.onSurface.copy(alpha = 0.12f),
        disabledContentColor: Color = MaterialTheme.colorScheme.onSurface.copy(alpha = 0.38f),
    ): ButtonColors = ButtonColors(
        containerColor = containerColor,
        contentColor = contentColor,
        disabledContainerColor = disabledContainerColor,
        disabledContentColor = disabledContentColor,
    )

    /**
     * Creates a [ButtonElevation] that will animate between the provided values according to the
     * Material specification for a [Button].
     *
     * @param defaultElevation the elevation used when the [Button] is enabled, and has no other
     * [Interaction]s.
     * @param pressedElevation the elevation used when this [Button] is enabled and pressed.
     * @param focusedElevation the elevation used when the [Button] is enabled and focused.
     * @param hoveredElevation the elevation used when the [Button] is enabled and hovered.
     * @param disabledElevation the elevation used when the [Button] is not enabled.
     */
    @Composable
    fun buttonElevation(
        defaultElevation: Dp = 0.dp,
        pressedElevation: Dp = 0.dp,
        focusedElevation: Dp = 0.dp,
        hoveredElevation: Dp = 1.dp,
        disabledElevation: Dp = 0.dp,
    ): ButtonElevation = ButtonElevation(
        defaultElevation = defaultElevation,
        pressedElevation = pressedElevation,
        focusedElevation = focusedElevation,
        hoveredElevation = hoveredElevation,
        disabledElevation = disabledElevation,
    )
}

/**
 * Represents the elevation for a button in different states.
 *
 * - See [M3ButtonDefaults.buttonElevation] for the default elevation used in a [Button].
 * - See [M3ButtonDefaults.elevatedButtonElevation] for the default elevation used in a
 * [ElevatedButton].
 */
@Stable
class ButtonElevation internal constructor(
    private val defaultElevation: Dp,
    private val pressedElevation: Dp,
    private val focusedElevation: Dp,
    private val hoveredElevation: Dp,
    private val disabledElevation: Dp,
) {
    /**
     * Represents the tonal elevation used in a button, depending on its [enabled] state and
     * [interactionSource]. This should typically be the same value as the [shadowElevation].
     *
     * Tonal elevation is used to apply a color shift to the surface to give the it higher emphasis.
     * When surface's color is [ColorScheme.surface], a higher elevation will result in a darker
     * color in light theme and lighter color in dark theme.
     *
     * See [shadowElevation] which controls the elevation of the shadow drawn around the button.
     *
     * @param enabled whether the button is enabled
     * @param interactionSource the [InteractionSource] for this button
     */
    @Composable
    internal fun tonalElevation(enabled: Boolean, interactionSource: InteractionSource): State<Dp> {
        return animateElevation(enabled = enabled, interactionSource = interactionSource)
    }

    /**
     * Represents the shadow elevation used in a button, depending on its [enabled] state and
     * [interactionSource]. This should typically be the same value as the [tonalElevation].
     *
     * Shadow elevation is used to apply a shadow around the button to give it higher emphasis.
     *
     * See [tonalElevation] which controls the elevation with a color shift to the surface.
     *
     * @param enabled whether the button is enabled
     * @param interactionSource the [InteractionSource] for this button
     */
    @Composable
    internal fun shadowElevation(
        enabled: Boolean,
        interactionSource: InteractionSource,
    ): State<Dp> {
        return animateElevation(enabled = enabled, interactionSource = interactionSource)
    }

    @Composable
    private fun animateElevation(
        enabled: Boolean,
        interactionSource: InteractionSource,
    ): State<Dp> {
        val interactions = remember { mutableStateListOf<Interaction>() }
        LaunchedEffect(interactionSource) {
            interactionSource.interactions.collect { interaction ->
                when (interaction) {
                    is HoverInteraction.Enter -> {
                        interactions.add(interaction)
                    }
                    is HoverInteraction.Exit -> {
                        interactions.remove(interaction.enter)
                    }
                    is FocusInteraction.Focus -> {
                        interactions.add(interaction)
                    }
                    is FocusInteraction.Unfocus -> {
                        interactions.remove(interaction.focus)
                    }
                    is PressInteraction.Press -> {
                        interactions.add(interaction)
                    }
                    is PressInteraction.Release -> {
                        interactions.remove(interaction.press)
                    }
                    is PressInteraction.Cancel -> {
                        interactions.remove(interaction.press)
                    }
                }
            }
        }

        val interaction = interactions.lastOrNull()

        val target =
            if (!enabled) {
                disabledElevation
            } else {
                when (interaction) {
                    is PressInteraction.Press -> pressedElevation
                    is HoverInteraction.Enter -> hoveredElevation
                    is FocusInteraction.Focus -> focusedElevation
                    else -> defaultElevation
                }
            }

        val animatable = remember { Animatable(target, Dp.VectorConverter) }

        if (!enabled) {
            // No transition when moving to a disabled state
            LaunchedEffect(target) { animatable.snapTo(target) }
        } else {
            LaunchedEffect(target) {
                val lastInteraction = when (animatable.targetValue) {
                    pressedElevation -> PressInteraction.Press(Offset.Zero)
                    hoveredElevation -> HoverInteraction.Enter()
                    focusedElevation -> FocusInteraction.Focus()
                    else -> null
                }
                animatable.animateElevation(
                    from = lastInteraction,
                    to = interaction,
                    target = target,
                )
            }
        }

        return animatable.asState()
    }

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

        if (defaultElevation != other.defaultElevation) return false
        if (pressedElevation != other.pressedElevation) return false
        if (focusedElevation != other.focusedElevation) return false
        if (hoveredElevation != other.hoveredElevation) return false
        if (disabledElevation != other.disabledElevation) return false

        return true
    }

    override fun hashCode(): Int {
        var result = defaultElevation.hashCode()
        result = 31 * result + pressedElevation.hashCode()
        result = 31 * result + focusedElevation.hashCode()
        result = 31 * result + hoveredElevation.hashCode()
        result = 31 * result + disabledElevation.hashCode()
        return result
    }
}

/**
 * Represents the container and content colors used in a button in different states.
 *
 * - See [M3ButtonDefaults.buttonColors] for the default colors used in a [Button].
 * - See [M3ButtonDefaults.elevatedButtonColors] for the default colors used in a [ElevatedButton].
 * - See [M3ButtonDefaults.textButtonColors] for the default colors used in a [TextButton].
 */
@Immutable
class ButtonColors internal constructor(
    private val containerColor: Color,
    private val contentColor: Color,
    private val disabledContainerColor: Color,
    private val disabledContentColor: Color,
) {
    /**
     * Represents the container color for this button, depending on [enabled].
     *
     * @param enabled whether the button is enabled
     */
    @Composable
    internal fun containerColor(enabled: Boolean): State<Color> {
        return rememberUpdatedState(if (enabled) containerColor else disabledContainerColor)
    }

    /**
     * Represents the content color for this button, depending on [enabled].
     *
     * @param enabled whether the button is enabled
     */
    @Composable
    internal fun contentColor(enabled: Boolean): State<Color> {
        return rememberUpdatedState(if (enabled) contentColor else disabledContentColor)
    }

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

        if (containerColor != other.containerColor) return false
        if (contentColor != other.contentColor) return false
        if (disabledContainerColor != other.disabledContainerColor) return false
        if (disabledContentColor != other.disabledContentColor) return false

        return true
    }

    override fun hashCode(): Int {
        var result = containerColor.hashCode()
        result = 31 * result + contentColor.hashCode()
        result = 31 * result + disabledContainerColor.hashCode()
        result = 31 * result + disabledContentColor.hashCode()
        return result
    }
}