CodePairScreen.kt

1package com.peachpasswords.ui.pairing23import com.peachpasswords.BuildConfig4import androidx.compose.foundation.background5import androidx.compose.foundation.clickable6import androidx.compose.foundation.shape.RoundedCornerShape7import androidx.compose.ui.draw.clip8import androidx.compose.ui.graphics.Color9import androidx.compose.foundation.layout.Arrangement10import androidx.compose.foundation.layout.Box11import androidx.compose.foundation.layout.Column12import androidx.compose.foundation.layout.Spacer13import androidx.compose.foundation.layout.fillMaxSize14import androidx.compose.foundation.layout.fillMaxWidth15import androidx.compose.foundation.layout.height16import androidx.compose.foundation.layout.padding17import androidx.compose.foundation.layout.systemBarsPadding18import androidx.compose.foundation.Canvas19import androidx.compose.material3.Text20import androidx.compose.runtime.Composable21import androidx.compose.runtime.LaunchedEffect22import androidx.compose.runtime.mutableStateOf23import androidx.compose.runtime.remember24import androidx.compose.runtime.setValue25import androidx.compose.runtime.getValue26import androidx.compose.ui.platform.LocalContext27import androidx.compose.ui.Alignment28import androidx.compose.ui.Modifier29import androidx.compose.ui.text.font.FontStyle30import androidx.compose.ui.text.style.TextAlign31import androidx.compose.ui.unit.dp32import androidx.compose.ui.unit.sp33import androidx.compose.ui.geometry.Offset34import androidx.compose.ui.geometry.Size35import androidx.hilt.navigation.compose.hiltViewModel36import androidx.lifecycle.compose.collectAsStateWithLifecycle37import com.peachpasswords.ui.components.BirdAnimation38import com.peachpasswords.ui.components.PairingAnimState39import com.peachpasswords.ui.theme.LocalPeachAccent40import com.peachpasswords.ui.theme.PeachSpacing41import com.peachpasswords.ui.theme.PeachType42import com.peachpasswords.ui.theme.ShellBackground43import com.peachpasswords.ui.theme.peachColors44import com.google.zxing.BarcodeFormat45import com.google.zxing.qrcode.QRCodeWriter4647/**48 * Pair a device by code. The phone shows the code; the browser types it in and49 * dials. Mirrors the extension's own phase structure (enter → connecting → sas50 * → paired), minus the entry field — the phone never types a code, it publishes51 * one.52 */53@Composable54fun CodePairScreen(55    onBack: () -> Unit,56    vm: CodePairViewModel = hiltViewModel(),57) {58    val state by vm.state.collectAsStateWithLifecycle()59    val context = LocalContext.current6061    var showBackgroundSyncPrompt by remember { mutableStateOf(false) }6263    LaunchedEffect(Unit) { vm.start() }6465    LaunchedEffect(state) {66        if (shouldPromptForBackgroundSync(state is CodePairUiState.Paired)) showBackgroundSyncPrompt = true67    }6869    if (showBackgroundSyncPrompt) {70        BackgroundSyncDialog { enabled ->71            showBackgroundSyncPrompt = false72            vm.setBackgroundSync(enabled)73            if (enabled) {74                vm.batteryExemptionIntent()?.let { intent ->75                    runCatching { context.startActivity(intent) }76                }77            }78        }79    }8081    val animState = when (state) {82        is CodePairUiState.Paired -> PairingAnimState.CONNECTED83        is CodePairUiState.AwaitingPeerConfirmation -> PairingAnimState.LISTENING84        else -> PairingAnimState.WAITING85    }8687    ShellBackground {88        Column(89            modifier = Modifier90                .fillMaxSize()91                .systemBarsPadding()92                .padding(horizontal = PeachSpacing.lg, vertical = PeachSpacing.md),93        ) {94            Box(Modifier.fillMaxWidth().weight(1f), contentAlignment = Alignment.Center) {95                BirdAnimation(animState, Modifier.fillMaxWidth().height(220.dp))96            }9798            when (val s = state) {99                is CodePairUiState.Starting -> Headline("Starting…", "Opening a secure relay pairing room.")100101                is CodePairUiState.ShowingInvitation -> {102                    Headline(103                        "Scan this in Peach",104                        "Connecting via secure relay — works anywhere. No vault or identity information is in this QR.",105                    )106                    Spacer(Modifier.height(PeachSpacing.md))107                    PairingQrCode(108                        value = s.invitation,109                        modifier = Modifier110                            .fillMaxWidth()111                            .height(260.dp),112                    )113                }114115                is CodePairUiState.AwaitingPeerConfirmation -> {116                    Headline(117                        "Confirm on the scanning device",118                        "If this code matches there, tap “They match” on that device. " +119                            "Peach finishes only after both sides save the pairing.",120                    )121                    Spacer(Modifier.height(PeachSpacing.lg))122                    Text(123                        text = s.sas,124                        color = LocalPeachAccent.current,125                        fontFamily = PeachType.Mono,126                        fontSize = 38.sp,127                        letterSpacing = 6.sp,128                        textAlign = TextAlign.Center,129                        modifier = Modifier.fillMaxWidth(),130                    )131                }132133                is CodePairUiState.Paired -> {134                    Headline("Paired", "${s.deviceName} will now sync through the relay.")135                    Spacer(Modifier.height(PeachSpacing.lg))136                    PillButton("Done", LocalPeachAccent.current, filled = true, onClick = onBack)137                }138139                is CodePairUiState.Expired -> {140                    Headline(141                        "That code expired",142                        "Codes are good for five minutes so one doesn't stay live on a phone in your pocket. Nothing was lost.",143                    )144                    Spacer(Modifier.height(PeachSpacing.lg))145                    PillButton("Show a new code", LocalPeachAccent.current, filled = true) { vm.restart() }146                }147148                is CodePairUiState.Failed -> {149                    Headline("Couldn't pair", failureCopy(s.reason))150                    Spacer(Modifier.height(PeachSpacing.lg))151                    PillButton("Back", LocalPeachAccent.current, filled = true, onClick = onBack)152                }153            }154            Spacer(Modifier.height(PeachSpacing.md))155        }156    }157}158159@Composable160private fun PairingQrCode(value: String, modifier: Modifier = Modifier) {161    val matrix = remember(value) {162        QRCodeWriter().encode(value, BarcodeFormat.QR_CODE, 0, 0)163    }164    Canvas(modifier = modifier) {165        val side = minOf(size.width, size.height)166        val module = side / matrix.width167        val qrSize = module * matrix.width168        val origin = Offset((size.width - qrSize) / 2f, (size.height - qrSize) / 2f)169        drawRect(Color.White, topLeft = origin, size = Size(qrSize, qrSize))170        for (y in 0 until matrix.height) {171            for (x in 0 until matrix.width) {172                if (matrix[x, y]) {173                    drawRect(174                        Color.Black,175                        topLeft = Offset(origin.x + x * module, origin.y + y * module),176                        size = Size(module + 0.5f, module + 0.5f),177                    )178                }179            }180        }181    }182}183184/** Full-width pill used for every action on the pairing screens. */185@Composable186internal fun PillButton(label: String, color: Color, filled: Boolean, onClick: () -> Unit) {187    val accent = LocalPeachAccent.current188    Box(189        modifier = Modifier190            .fillMaxWidth()191            .clip(RoundedCornerShape(14.dp))192            .background(if (filled) accent.copy(alpha = 0.14f) else Color.Transparent)193            .clickable(onClick = onClick)194            .padding(vertical = PeachSpacing.md),195        contentAlignment = Alignment.Center,196    ) {197        Text(label, color = if (filled) accent else color, fontFamily = PeachType.Mono, fontSize = 13.sp)198    }199}200201private fun failureCopy(reason: String): String = when (reason) {202    "vault_locked" -> "Unlock your vault first — pairing shares the key that protects it."203    "no_local_network" -> "This phone isn't on a Wi-Fi network, so there's no address to hand out."204    "sas_mismatch" -> "The codes didn't match, so nothing was saved. That's the right outcome if you didn't expect a connection."205    "sync_disabled" -> "Sync is switched off for this vault. Turn it on in Settings → Sync first."206    // Pairing hands the relay address to the other device, so there is nothing207    // honest to put in the code until one exists.208    "private_relay_unset" -> "Private relay chosen but no address set. Enter your relay URL in Settings → Sync first."209    // Every other reason collapsed into this one sentence, which is fine for a210    // user and useless for anyone debugging: "bad_token", "no_hello" and a raw211    // exception message all looked identical on screen. Debug builds show the212    // real one.213    else -> "Something interrupted the connection. Try again."214        .let { if (BuildConfig.DEBUG) "$it\n\n[$reason]" else it }215}216217@Composable218private fun Headline(title: String, body: String) {219    Column(220        modifier = Modifier.fillMaxWidth(),221        horizontalAlignment = Alignment.CenterHorizontally,222        verticalArrangement = Arrangement.Center,223    ) {224        Text(225            title,226            color = peachColors.T0,227            fontFamily = PeachType.Display,228            fontStyle = FontStyle.Italic,229            fontSize = 22.sp,230            textAlign = TextAlign.Center,231        )232        Spacer(Modifier.height(PeachSpacing.xs))233        Text(234            body,235            color = peachColors.T2,236            fontFamily = PeachType.Body,237            fontSize = 13.sp,238            textAlign = TextAlign.Center,239        )240    }241}