session-android/app/src/main/java/org/thoughtcrime/securesms/ui/Themes.kt

package org.thoughtcrime.securesms.ui

import android.content.Context
import androidx.annotation.AttrRes
import androidx.appcompat.view.ContextThemeWrapper
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.material.LocalContentColor
import androidx.compose.material.MaterialTheme
import androidx.compose.material.Shapes
import androidx.compose.material.Typography
import androidx.compose.runtime.Composable
import androidx.compose.runtime.CompositionLocalProvider
import androidx.compose.runtime.remember
import androidx.compose.runtime.staticCompositionLocalOf
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.platform.LocalContext
import androidx.compose.ui.text.TextStyle
import androidx.compose.ui.text.font.FontWeight
import androidx.compose.ui.tooling.preview.PreviewParameterProvider
import androidx.compose.ui.unit.TextUnit
import androidx.compose.ui.unit.sp
import com.google.accompanist.themeadapter.appcompat.createAppCompatTheme
import com.google.android.material.color.MaterialColors
import network.loki.messenger.R

val LocalExtraColors = staticCompositionLocalOf<ExtraColors> { error("No Custom Attribute value provided") }


data class ExtraColors(
    val settingsBackground: Color,
    val prominentButtonColor: Color,
    val lightCell: Color,
    val onLightCell: Color,
)

/**
 * Converts current Theme to Compose Theme.
 */
@Composable
fun AppTheme(
    content: @Composable () -> Unit
) {
    val context = LocalContext.current

    val extraColors = context.run {
        ExtraColors(
            settingsBackground = getColorFromTheme(R.attr.colorSettingsBackground),
            prominentButtonColor = getColorFromTheme(R.attr.prominentButtonColor),
            lightCell = getColorFromTheme(R.attr.lightCell),
            onLightCell = getColorFromTheme(R.attr.onLightCell),
        )
    }

    val surface = context.getColorFromTheme(R.attr.colorSettingsBackground)

    CompositionLocalProvider(LocalExtraColors provides extraColors) {
        AppCompatTheme(surface = surface) {
            content()
        }
    }
}

@Composable
fun AppCompatTheme(
    context: Context = LocalContext.current,
    readColors: Boolean = true,
    typography: Typography = sessionTypography,
    shapes: Shapes = MaterialTheme.shapes,
    surface: Color? = null,
    content: @Composable () -> Unit
) {
    val themeParams = remember(context.theme) {
        context.createAppCompatTheme(
            readColors = readColors,
            readTypography = false
        )
    }

    val colors = themeParams.colors ?: MaterialTheme.colors

    MaterialTheme(
        colors = colors.copy(
            surface = surface ?: colors.surface
        ),
        typography = typography,
        shapes = shapes,
    ) {
        // We update the LocalContentColor to match our onBackground. This allows the default
        // content color to be more appropriate to the theme background
        CompositionLocalProvider(
            LocalContentColor provides MaterialTheme.colors.onBackground,
            content = content
        )
    }
}

fun boldStyle(size: TextUnit) = TextStyle.Default.copy(
    fontWeight = FontWeight.Bold,
    fontSize = size
)

fun defaultStyle(size: TextUnit) = TextStyle.Default.copy(fontSize = size)

val sessionTypography = Typography(
    h1 = boldStyle(36.sp),
    h2 = boldStyle(32.sp),
    h3 = boldStyle(29.sp),
    h4 = boldStyle(26.sp),
    h5 = boldStyle(23.sp),
    h6 = boldStyle(20.sp),
)

val Typography.base get() = defaultStyle(14.sp)
val Typography.baseBold get() = boldStyle(14.sp)
val Typography.small get() = defaultStyle(12.sp)
val Typography.extraSmall get() = defaultStyle(11.sp)

val Typography.h7 get() = boldStyle(18.sp)
val Typography.h8 get() = boldStyle(16.sp)
val Typography.h9 get() = boldStyle(14.sp)

fun Context.getColorFromTheme(@AttrRes attr: Int, defaultValue: Int = 0x0): Color =
    MaterialColors.getColor(this, attr, defaultValue).let(::Color)

/**
 * Set the theme and a background for Compose Previews.
 */
@Composable
fun PreviewTheme(
    themeResId: Int,
    content: @Composable () -> Unit
) {
    CompositionLocalProvider(
        LocalContext provides ContextThemeWrapper(LocalContext.current, themeResId)
    ) {
        AppTheme {
            Box(modifier = Modifier.background(color = MaterialTheme.colors.background)) {
                content()
            }
        }
    }
}

class ThemeResPreviewParameterProvider : PreviewParameterProvider<Int> {
    override val values = sequenceOf(
        R.style.Classic_Dark,
        R.style.Classic_Light,
        R.style.Ocean_Dark,
        R.style.Ocean_Light,
    )
}