package coffee.liz.abstractionengine.game

import androidx.compose.foundation.Canvas
import androidx.compose.runtime.*
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import coffee.liz.ecs.World
import kotlinx.coroutines.isActive
import kotlin.time.Duration.Companion.nanoseconds

/**
 * Manages and paints the [World].
 */
@Composable
fun Game(
    world: World,
    content: @Composable () -> Unit,
) {
    var frameCount by remember { mutableStateOf(0) }

    LaunchedEffect(world) {
        var lastUpdate: Long? = null

        while (isActive) {
            withFrameNanos { frameTimeNanos ->
                frameCount++
            }
        }
    }

    content()
}

@Composable
fun GameCanvas(
    world: World,
    renderSystem: Renderer,
    backgroundColor: Color = Color.Transparent,
    modifier: Modifier = Modifier,
) {
    Canvas(modifier = modifier) {
        // Clear background
        drawRect(backgroundColor)

        // Render all sprites
        renderSystem.render(world, this)
    }
}