package com.example.aiapp

import androidx.compose.runtime.Composable
import androidx.compose.runtime.LaunchedEffect
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableIntStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue

/**
 * The app's root screen, in the full-width panel [SidePanels] slides over a session from the left.
 *
 * Not a list of its own but [MainScreen] itself, and the whole width of the screen: what a right
 * swipe gets is the screen Back would have got, moved over the session instead of replacing it. The
 * session stays composed underneath, with its stream open and its draft and scroll position where
 * they were, so swiping the panel back off returns to it for nothing -- where Back and a tap costs
 * the whole transcript over the tunnel again.
 *
 * Tapping the session already open is that same swipe back rather than a fresh screen: reopening it
 * would hand [SessionScreen] a new summary for the conversation it is already showing.
 *
 * [onGone] is the one thing the list can do that this panel cannot survive -- deleting the very
 * session it is drawn over. There is nothing left to swipe back into, so that closes the screen.
 */
@Composable
fun MainPanel(
    settings: ServerSettings,
    sessionId: String,
    active: Boolean,
    onOpen: (SessionSummary) -> Unit,
    onSpawn: () -> Unit,
    onImported: (SessionSummary) -> Unit,
    onSettings: () -> Unit,
    onProvider: (String, String) -> Unit,
    onClose: () -> Unit,
    onGone: () -> Unit,
) {
    // Asked again each time the panel opens: who is working and who is waiting on an answer is
    // exactly what changed while the session underneath was being read.
    var reloadToken by remember(sessionId) { mutableIntStateOf(0) }
    LaunchedEffect(active) { if (active) reloadToken++ }

    MainScreen(
        settings = settings,
        reloadToken = reloadToken,
        onOpen = { if (it.id == sessionId) onClose() else onOpen(it) },
        onSpawn = onSpawn,
        onImported = onImported,
        onSettings = onSettings,
        onProvider = onProvider,
        onDeleted = { if (it == sessionId) onGone() },
    )
}