Feature/profile tools

app/src/main/java/io/nekohasekai/sagernet/ktx/CountryFlags.kt

@@ -0,0 +1,150 @@
+package io.nekohasekai.sagernet.ktx
+
+import android.content.Context
+import io.nekohasekai.sagernet.database.ProxyEntity
+import libcore.Libcore
+import java.net.InetAddress
+import java.util.concurrent.ConcurrentHashMap
+
+/**
+ * IP 归属地国旗缓存。
+ *
+ * 查询走本地 geoip.db（无需联网）：服务器地址 -> IP -> ISO 国家码。
+ * 结果按 服务器地址 持久化到 SharedPreferences，重启后仍然有效；
+ * profileId 映射只存在内存里，卡片首次绑定时按地址回填。
+ */
+object CountryFlags {
+
+    private const val PREFS_NAME = "country_flags"
+    private const val RETRY_COOL_DOWN_MS = 60_000L
+
+    private val byProfile = ConcurrentHashMap<Long, String>()      // profileId -> ISO 代码
+    private val byHost = ConcurrentHashMap<String, String>()       // serverAddress -> ISO 代码
+    private val failedAt = ConcurrentHashMap<String, Long>()       // 失败时间戳，冷却重试
+
+    private val prefs by lazy {
+        app.getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE)
+    }
+
+    init {
+        // 把上次运行持久化的结果读回内存
+        try {
+            prefs.all.forEach { (host, code) ->
+                if (host is String && code is String && code.length == 2) {
+                    byHost[host] = code
+                }
+            }
+        } catch (ignored: Exception) {
+        }
+    }
+
+    fun get(profileId: Long): String? = byProfile[profileId]
+
+    /** 优先按 profile 取，其次按服务器地址取（持久化数据在重启后走这条路径） */
+    fun resolve(profile: ProxyEntity): String? {
+        byProfile[profile.id]?.let { return it }
+        val host = hostOf(profile)
+        if (host.isBlank()) return null
+        return byHost[host]?.also { byProfile[profile.id] = it }
+    }
+
+    fun forget(profileId: Long) {
+        byProfile.remove(profileId)
+    }
+
+    private fun hostOf(profile: ProxyEntity): String = try {
+        profile.requireBean().serverAddress.orEmpty()
+    } catch (e: Exception) {
+        ""
+    }
+
+    /**
+     * 查询节点服务器地址的归属国家，阻塞调用，必须在后台线程执行。
+     * 返回 ISO 3166-1 两位代码，查不到返回空串。
+     */
+    fun query(profile: ProxyEntity): String {
+        val host = hostOf(profile)
+        if (host.isBlank()) return ""
+
+        byHost[host]?.let { cached ->
+            byProfile[profile.id] = cached
+            return cached
+        }
+
+        val failedTime = failedAt[host]
+        if (failedTime != null &&
+            System.currentTimeMillis() - failedTime < RETRY_COOL_DOWN_MS
+        ) return ""
+
+        // 域名先解析成 IP（IP 字面量会直接返回，不产生 DNS 请求）
+        val ip = try {
+            InetAddress.getByName(host).hostAddress
+        } catch (e: Exception) {
+            null
+        }
+        if (ip.isNullOrBlank()) {
+            failedAt[host] = System.currentTimeMillis()
+            return ""
+        }
+
+        val code = try {
+            Libcore.queryGeoIPCountry(ip) ?: ""
+        } catch (e: Exception) {
+            ""
+        }
+
+        if (code.length == 2) {
+            remember(host, profile.id, code)
+            return code
+        }
+        failedAt[host] = System.currentTimeMillis()
+        return ""
+    }
+
+    private fun remember(host: String, profileId: Long, code: String) {
+        byHost[host] = code
+        byProfile[profileId] = code
+        failedAt.remove(host)
+        try {
+            prefs.edit().putString(host, code).apply()
+        } catch (ignored: Exception) {
+        }
+    }
+
+    /**
+     * 清除指定节点的图标缓存（内存 + 持久化）。
+     * 「清理测试结果」时调用，让图标与延迟一起消失。
+     */
+    fun forgetProfiles(profiles: List<ProxyEntity>) {
+        if (profiles.isEmpty()) return
+        val editor = prefs.edit()
+        var changed = false
+        for (profile in profiles) {
+            byProfile.remove(profile.id)
+            val host = hostOf(profile)
+            if (host.isBlank()) continue
+            byHost.remove(host)
+            failedAt.remove(host)
+            editor.remove(host)
+            changed = true
+        }
+        if (changed) {
+            try {
+                editor.apply()
+            } catch (ignored: Exception) {
+            }
+        }
+    }
+
+    /** ISO 国家代码转国旗 emoji，如 "US" -> 🇺🇸 */
+    fun flagOf(code: String?): String {
+        if (code == null || code.length != 2) return ""
+        val upper = code.uppercase()
+        val first = upper[0]
+        val second = upper[1]
+        if (first !in 'A'..'Z' || second !in 'A'..'Z') return ""
+        val base = 0x1F1E6 // Regional Indicator Symbol Letter A
+        return String(Character.toChars(base + (first - 'A'))) +
+                String(Character.toChars(base + (second - 'A')))
+    }
+}