implement front proxy & selector

app/src/main/java/io/nekohasekai/sagernet/bg/BaseService.kt

@@ -47,7 +47,7 @@ class BaseService {
         val receiver = broadcastReceiver { _, intent ->
             when (intent.action) {
                 Intent.ACTION_SHUTDOWN -> service.persistStats()
-                Action.RELOAD -> service.forceLoad()
+                Action.RELOAD -> service.reload()
                 Action.SWITCH_WAKE_LOCK -> runOnDefaultDispatcher { service.switchWakeLock() }
                 else -> service.stopRunner()
             }
@@ -82,7 +82,7 @@ class BaseService {
             cb.updateWakeLockStatus(data?.proxy?.service?.wakeLock != null)
         }
 
-        val boardcastMutex = Mutex()
+        private val boardcastMutex = Mutex()
 
         suspend fun broadcast(work: (ISagerNetServiceCallback) -> Unit) {
             boardcastMutex.withLock {
@@ -143,10 +143,23 @@ class BaseService {
         fun onBind(intent: Intent): IBinder? =
             if (intent.action == Action.SERVICE) data.binder else null
 
-        fun forceLoad() {
+        fun reload() {
             if (DataStore.selectedProxy == 0L) {
                 stopRunner(false, (this as Context).getString(R.string.profile_empty))
             }
+            if (canReloadSelector()) {
+                var tag = ""
+                data.proxy!!.config.trafficMap.forEach { (t, list) ->
+                    if (list.map { it.id }.contains(DataStore.selectedProxy)) {
+                        tag = t
+                    }
+                }
+                if (tag.isNotBlank()) {
+                    val success = data.proxy!!.box.selectOutbound(tag)
+                    Logs.d("selectOutbound $tag $success")
+                }
+                return
+            }
             val s = data.state
             when {
                 s == State.Stopped -> startRunner()
@@ -155,6 +168,18 @@ class BaseService {
             }
         }
 
+        fun canReloadSelector(): Boolean {
+            if ((data.proxy?.config?.selectorGroupId ?: -1L) < 0) return false
+            val ent = SagerDatabase.proxyDao.getById(DataStore.selectedProxy) ?: return false
+            val tmpBox = ProxyInstance(ent)
+            tmpBox.buildConfigTmp()
+            if (tmpBox.lastSelectorGroupId == data.proxy?.lastSelectorGroupId) {
+                return true
+                // TODO if profile changed?
+            }
+            return false
+        }
+
         suspend fun startProcesses() {
             data.proxy!!.launch()
         }

app/src/main/java/io/nekohasekai/sagernet/bg/proto/ProxyInstance.kt

@@ -8,18 +8,27 @@ import io.nekohasekai.sagernet.ktx.runOnIoDispatcher
 import kotlinx.coroutines.runBlocking
 import moe.matsuri.nb4a.utils.JavaUtil
 
-class ProxyInstance(profile: ProxyEntity, val service: BaseService.Interface) :
+class ProxyInstance(profile: ProxyEntity, var service: BaseService.Interface? = null) :
     BoxInstance(profile) {
 
+    var lastSelectorGroupId = -1L
+
     // for TrafficLooper
     private var looper: TrafficLooper? = null
 
     override fun buildConfig() {
         super.buildConfig()
+        lastSelectorGroupId = super.config.selectorGroupId
+        //
         Logs.d(config.config)
         if (BuildConfig.DEBUG) Logs.d(JavaUtil.gson.toJson(config.trafficMap))
     }
 
+    // only use this in temporary instance
+    fun buildConfigTmp() {
+        buildConfig()
+    }
+
     override suspend fun init() {
         super.init()
         pluginConfigs.forEach { (_, plugin) ->
@@ -32,7 +41,7 @@ class ProxyInstance(profile: ProxyEntity, val service: BaseService.Interface) :
         box.setAsMain()
         super.launch()
         runOnIoDispatcher {
-            looper = TrafficLooper(service.data, this)
+            looper = service?.let { TrafficLooper(it.data, this) }
             looper?.start()
         }
     }

app/src/main/java/io/nekohasekai/sagernet/fmt/ConfigBuilder.kt

@@ -54,6 +54,7 @@ class ConfigBuildResult(
     var mainEntId: Long,
     var trafficMap: Map<String, List<ProxyEntity>>,
     val alerts: List<Pair<Int, String>>,
+    val selectorGroupId: Long,
 ) {
     data class IndexEntity(var chain: LinkedHashMap<Int, ProxyEntity>)
 }
@@ -84,16 +85,19 @@ fun buildConfig(
                 listOf(),
                 proxy.id, //
                 mapOf(TAG_PROXY to listOf(proxy)), //
-                listOf()
+                listOf(),
+                -1L
             )
         }
     }
 
     val trafficMap = HashMap<String, MutableList<ProxyEntity>>()
     val globalOutbounds = ArrayList<Long>()
+    val group = SagerDatabase.groupDao.getById(proxy.groupId)
     var optionsToMerge = ""
 
     fun ProxyEntity.resolveChain(): MutableList<ProxyEntity> {
+        val frontProxy = group?.frontProxy?.let { SagerDatabase.proxyDao.getById(it) }
         val bean = requireBean()
         if (bean is ChainBean) {
             val beans = SagerDatabase.proxyDao.getEntities(bean.proxies)
@@ -103,18 +107,26 @@ fun buildConfig(
                 val item = beansMap[proxyId] ?: continue
                 beanList.addAll(item.resolveChain())
             }
-            return beanList.asReversed()
+            return if (frontProxy == null) {
+                beanList.asReversed()
+            } else {
+                beanList.add(0, frontProxy)
+                beanList.asReversed()
+            }
+        }
+        return if (frontProxy == null) {
+            mutableListOf(this)
+        } else {
+            mutableListOf(this, frontProxy)
         }
-        return mutableListOf(this)
     }
 
-    val proxies = proxy.resolveChain()
     val extraRules = if (forTest) listOf() else SagerDatabase.rulesDao.enabledRules()
     val extraProxies =
-        if (forTest) mapOf() else SagerDatabase.proxyDao.getEntities(extraRules.mapNotNull { rule ->
+        (if (forTest) mapOf() else SagerDatabase.proxyDao.getEntities(extraRules.mapNotNull { rule ->
             rule.outbound.takeIf { it > 0 && it != proxy.id }
-        }.toHashSet().toList()).associate { it.id to it.resolveChain() }
+        }.toHashSet().toList()).associate { it.id to it.resolveChain() }).toMutableMap()
-
+    val buildSelector = !forTest && group?.isSelector == true
     val uidListDNSRemote = mutableListOf<Int>()
     val uidListDNSDirect = mutableListOf<Int>()
     val domainListDNSRemote = mutableListOf<String>()
@@ -444,8 +456,23 @@ fun buildConfig(
             return chainTagOut
         }
 
-        val tagProxy = buildChain(0, proxies)
+        // build outbounds
         val tagMap = mutableMapOf<Long, String>()
+        if (buildSelector) {
+            val list = group?.id?.let { SagerDatabase.proxyDao.getByGroup(it) }
+            list?.forEach {
+                tagMap[it.id] = buildChain(it.id, it.resolveChain())
+            }
+            outbounds.add(0, Outbound_SelectorOptions().apply {
+                type = "selector"
+                tag = TAG_PROXY
+                default_ = tagMap[proxy.id]
+                outbounds = tagMap.values.toList()
+            }.asMap())
+        } else {
+            buildChain(0, proxy.resolveChain())
+        }
+        // build outbounds from route item
         extraProxies.forEach { (key, entities) ->
             tagMap[key] = buildChain(key, entities)
         }
@@ -521,10 +548,10 @@ fun buildConfig(
                 }
 
                 outbound = when (val outId = rule.outbound) {
-                    0L -> tagProxy
+                    0L -> TAG_PROXY
                     -1L -> TAG_BYPASS
                     -2L -> TAG_BLOCK
-                    else -> if (outId == proxy.id) tagProxy else tagMap[outId]
+                    else -> if (outId == proxy.id) TAG_PROXY else tagMap[outId]
                         ?: throw Exception("invalid rule")
                 }
             })
@@ -569,7 +596,7 @@ fun buildConfig(
         for (dns in remoteDns) {
             if (!dns.isIpAddress()) continue
             route.rules.add(Rule_DefaultOptions().apply {
-                outbound = tagProxy
+                outbound = TAG_PROXY
                 ip_cidr = listOf(dns)
             })
         }
@@ -721,7 +748,8 @@ fun buildConfig(
             externalIndexMap,
             proxy.id,
             trafficMap,
-            alerts
+            alerts,
+            if (buildSelector) group!!.id else -1L
         )
     }
 

libcore/box.go

@@ -24,6 +24,7 @@ import (
 
 	sblog "github.com/sagernet/sing-box/log"
 	"github.com/sagernet/sing-box/option"
+	"github.com/sagernet/sing-box/outbound"
 )
 
 var mainInstance *BoxInstance
@@ -71,6 +72,7 @@ type BoxInstance struct {
 	state  int
 
 	v2api    *boxapi.SbV2rayServer
+	selector *outbound.Selector
 
 	ForTest bool
 }
@@ -111,6 +113,13 @@ func NewSingBoxInstance(config string) (b *BoxInstance, err error) {
 	platformFormatter := platformFormatter_.Interface().(*sblog.Formatter)
 	platformFormatter.DisableColors = true
 
+	// selector
+	if proxy, ok := b.Router().Outbound("proxy"); ok {
+		if selector, ok := proxy.(*outbound.Selector); ok {
+			b.selector = selector
+		}
+	}
+
 	return b, nil
 }
 
@@ -182,6 +191,13 @@ func (b *BoxInstance) QueryStats(tag, direct string) int64 {
 	return b.v2api.QueryStats(fmt.Sprintf("outbound>>>%s>>>traffic>>>%s", tag, direct))
 }
 
+func (b *BoxInstance) SelectOutbound(tag string) bool {
+	if b.selector != nil {
+		return b.selector.SelectOutbound(tag)
+	}
+	return false
+}
+
 func UrlTest(i *BoxInstance, link string, timeout int32) (int32, error) {
 	if i == nil {
 		// test current