Android：合入服务商预设与可搜索模型选择

app/src/main/java/com/frischar/fantareal/domain/llm/ModelCatalog.kt

@@ -0,0 +1,121 @@
+package com.frischar.fantareal.domain.llm
+
+data class ModelProviderPreset(
+    val id: String,
+    val label: String,
+    val baseUrl: String,
+    val recommendedModel: String,
+    val helper: String,
+    val requiresApiKey: Boolean = true
+)
+
+object ModelProviderPresets {
+    val all = listOf(
+        ModelProviderPreset(
+            id = "custom",
+            label = "自定义",
+            baseUrl = "",
+            recommendedModel = "",
+            helper = "保留当前填写内容，适合本地或其他 OpenAI-compatible 服务。",
+            requiresApiKey = false
+        ),
+        ModelProviderPreset(
+            id = "deepseek",
+            label = "DeepSeek",
+            baseUrl = "https://api.deepseek.com/v1",
+            recommendedModel = "deepseek-chat",
+            helper = "填入 DeepSeek 官方兼容地址，并优先选择 deepseek-chat。"
+        ),
+        ModelProviderPreset(
+            id = "openai",
+            label = "OpenAI",
+            baseUrl = "https://api.openai.com/v1",
+            recommendedModel = "gpt-4.1-mini",
+            helper = "填入 OpenAI 官方地址；拉取后以账号实际可用模型为准。"
+        ),
+        ModelProviderPreset(
+            id = "minimax",
+            label = "MiniMax",
+            baseUrl = "https://api.minimaxi.com/v1",
+            recommendedModel = "MiniMax-M3",
+            helper = "填入 MiniMax 国内官方 OpenAI-compatible 地址。"
+        ),
+        ModelProviderPreset(
+            id = "openrouter",
+            label = "OpenRouter",
+            baseUrl = "https://openrouter.ai/api/v1",
+            recommendedModel = "openrouter/auto",
+            helper = "优先使用 openrouter/auto，也可以从账号可用列表中改选。"
+        ),
+        ModelProviderPreset(
+            id = "siliconflow",
+            label = "SiliconFlow",
+            baseUrl = "https://api.siliconflow.cn/v1",
+            recommendedModel = "",
+            helper = "填入 SiliconFlow 地址，拉取后从账号可用模型中选择。"
+        )
+    )
+
+    fun find(id: String): ModelProviderPreset = all.firstOrNull { it.id == id } ?: all.first()
+
+    fun detect(baseUrl: String): ModelProviderPreset {
+        val normalized = baseUrl.trim().trimEnd('/').lowercase()
+        return all.firstOrNull { preset ->
+            preset.baseUrl.isNotBlank() && preset.baseUrl.trimEnd('/').lowercase() == normalized
+        } ?: all.first()
+    }
+}
+
+internal fun choosePreferredChatModel(
+    currentModel: String,
+    recommendedModel: String,
+    availableModels: List<String>
+): String {
+    val models = availableModels.map(String::trim).filter(String::isNotBlank).distinct()
+    val current = currentModel.trim()
+    val recommended = recommendedModel.trim()
+
+    if (current in models) return current
+    if (recommended in models) return recommended
+
+    val chatCandidates = models.filterNot(::isClearlyNonChatModel)
+    return chatCandidates.singleOrNull().orEmpty()
+}
+
+internal fun shouldClearApiKeyForProviderSwitch(
+    currentBaseUrl: String,
+    nextBaseUrl: String,
+    apiKey: String
+): Boolean {
+    if (apiKey.isBlank()) return false
+
+    val currentProvider = normalizeProviderBaseUrl(currentBaseUrl)
+    val nextProvider = normalizeProviderBaseUrl(nextBaseUrl)
+    return nextProvider.isNotBlank() && currentProvider != nextProvider
+}
+
+private fun normalizeProviderBaseUrl(value: String): String = value
+    .trim()
+    .trimEnd('/')
+    .removeSuffix("/chat/completions")
+    .removeSuffix("/models")
+    .trimEnd('/')
+    .lowercase()
+
+private fun isClearlyNonChatModel(model: String): Boolean {
+    val normalized = model.lowercase()
+    return listOf(
+        "embedding",
+        "rerank",
+        "moderation",
+        "whisper",
+        "tts",
+        "speech",
+        "audio",
+        "image",
+        "dall-e",
+        "stable-diffusion",
+        "transcription",
+        "ocr"
+    ).any(normalized::contains) || normalized.startsWith("bge-")
+}

app/src/main/java/com/frischar/fantareal/domain/llm/OpenAiProvider.kt

@@ -6,16 +6,14 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.flow
 import kotlinx.coroutines.flow.flowOn
+import kotlinx.coroutines.withContext
 import kotlinx.serialization.Serializable
 import kotlinx.serialization.encodeToString
 import kotlinx.serialization.json.JsonArray
 import kotlinx.serialization.json.JsonElement
 import kotlinx.serialization.json.JsonObject
 import kotlinx.serialization.json.JsonPrimitive
 import kotlinx.serialization.json.contentOrNull
-import kotlinx.serialization.json.jsonArray
-import kotlinx.serialization.json.jsonObject
-import kotlinx.serialization.json.jsonPrimitive
 import okhttp3.MediaType.Companion.toMediaType
 import okhttp3.OkHttpClient
 import okhttp3.Request
@@ -67,6 +65,40 @@ class OpenAiProvider(
         .connectTimeout(60, TimeUnit.SECONDS)
         .build()
 
+    suspend fun fetchAvailableModels(): List<String> = withContext(Dispatchers.IO) {
+        val httpReq = Request.Builder()
+            .url(normalizeEndpoint(baseUrl, "models"))
+            .apply {
+                if (apiKey.isNotBlank()) {
+                    addHeader("Authorization", "Bearer $apiKey")
+                }
+            }
+            .get()
+            .build()
+
+        client.newCall(httpReq).execute().use { response ->
+            if (!response.isSuccessful) {
+                throw IllegalStateException("拉取模型失败：HTTP ${response.code}")
+            }
+
+            val responseText = response.body?.string().orEmpty()
+            val root = runCatching { AppJson.parseToJsonElement(responseText) as? JsonObject }
+                .getOrNull()
+                ?: throw IllegalStateException("模型列表接口没有返回有效 JSON")
+            val rows = root["data"] as? JsonArray
+                ?: throw IllegalStateException("模型列表格式无效：缺少 data 数组")
+
+            rows.mapNotNull { item ->
+                (item as? JsonObject)
+                    ?.get("id")
+                    ?.let { it as? JsonPrimitive }
+                    ?.contentOrNull
+                    ?.trim()
+                    ?.takeIf(String::isNotBlank)
+            }.distinct()
+        }
+    }
+
     fun stream(request: LlmRequest): Flow<LlmStreamEvent> = flow {
         val messages = mutableListOf<OpenAiMessage>()
         if (request.system != null) {
@@ -84,7 +116,7 @@ class OpenAiProvider(
         try {
             val jsonBody = AppJson.encodeToString(openAiReq)
             val httpReq = Request.Builder()
-                .url(normalizeEndpoint(baseUrl))
+                .url(normalizeEndpoint(baseUrl, "chat/completions"))
                 .apply {
                     if (apiKey.isNotBlank()) {
                         addHeader("Authorization", "Bearer $apiKey")
@@ -168,18 +200,24 @@ class OpenAiProvider(
         }
     }.flowOn(Dispatchers.IO)
 
-    private fun normalizeEndpoint(value: String): String {
+    private fun normalizeEndpoint(value: String, endpoint: String): String {
         val trimmed = value.trim().trimEnd('/')
         require(trimmed.isNotBlank()) { "API base URL is empty" }
         require(trimmed.startsWith("http://") || trimmed.startsWith("https://")) {
             "API base URL must start with http:// or https://"
         }
-        return if (trimmed.endsWith("/chat/completions")) {
-            trimmed
-        } else if (!trimmed.substringAfter("://", "").contains("/")) {
-            "$trimmed/v1/chat/completions"
+
+        val cleanEndpoint = endpoint.trim('/')
+        val endpointBase = when {
+            trimmed.endsWith("/chat/completions") -> trimmed.removeSuffix("/chat/completions")
+            trimmed.endsWith("/models") -> trimmed.removeSuffix("/models")
+            else -> trimmed
+        }.trimEnd('/')
+
+        return if (!endpointBase.substringAfter("://", "").contains("/")) {
+            "$endpointBase/v1/$cleanEndpoint"
         } else {
-            "$trimmed/chat/completions"
+            "$endpointBase/$cleanEndpoint"
         }
     }
 

app/src/main/java/com/frischar/fantareal/ui/app/AppScaffold.kt

@@ -206,6 +206,9 @@ fun AppScaffold() {
                     onBaseUrlChange = settingsViewModel::updateApiBaseUrl,
                     onApiKeyChange = settingsViewModel::updateApiKey,
                     onModelNameChange = settingsViewModel::updateModel,
+                    onProviderPresetChange = settingsViewModel::selectProviderPreset,
+                    onApplyProviderPreset = settingsViewModel::applyProviderPresetAndFetch,
+                    onFetchModels = settingsViewModel::fetchModels,
                     onTemperatureChange = settingsViewModel::updateTemperature,
                     onSupportStreamingChange = settingsViewModel::updateSupportStreaming,
                     onOpenaiFormatChange = settingsViewModel::updateOpenaiFormat,