The first 2 weeks is ended.

apps/web/server/utils/ai-provider.ts

@@ -0,0 +1,103 @@
+import { z } from 'zod'
+
+const ProviderSchema = z.enum(['openrouter', 'deepseek'])
+const CompletionResponseSchema = z.object({
+  choices: z.array(z.object({
+    message: z.object({ content: z.string().min(1) }),
+  })).min(1),
+})
+
+export type AiProvider = z.infer<typeof ProviderSchema>
+
+export interface AiRuntimeConfig {
+  aiProvider?: unknown
+  openrouterApiKey?: unknown
+  openrouterModel?: unknown
+  openrouterApiEndpoint?: unknown
+  deepseekApiKey?: unknown
+  deepseekModel?: unknown
+  deepseekApiEndpoint?: unknown
+}
+
+export interface JsonCompletionRequest {
+  system: string
+  messages: Array<{ role: 'user' | 'assistant'; content: string }>
+  schemaName: string
+  jsonSchema: Record<string, unknown>
+}
+
+interface JsonCompletion {
+  endpoint: string
+  headers: Record<string, string>
+  body: Record<string, unknown>
+}
+
+const nonEmptyString = (value: unknown, name: string) => {
+  const result = z.string().trim().min(1).safeParse(value)
+  if (!result.success) throw new Error(`${name} is required for the selected AI provider`)
+  return result.data
+}
+
+const endpoint = (value: unknown, fallback: string, name: string) => {
+  const result = z.string().url().safeParse(value || fallback)
+  if (!result.success) throw new Error(`${name} must be a valid URL`)
+  return result.data
+}
+
+export function resolveAiProvider(config: AiRuntimeConfig) {
+  const providerResult = ProviderSchema.safeParse(config.aiProvider || 'openrouter')
+  if (!providerResult.success) throw new Error('AI_PROVIDER must be either "openrouter" or "deepseek"')
+
+  if (providerResult.data === 'deepseek') {
+    return {
+      provider: 'deepseek' as const,
+      apiKey: nonEmptyString(config.deepseekApiKey, 'DEEPSEEK_API_KEY'),
+      model: nonEmptyString(config.deepseekModel || 'deepseek-v4-flash', 'DEEPSEEK_MODEL'),
+      endpoint: endpoint(config.deepseekApiEndpoint, 'https://api.deepseek.com/chat/completions', 'DEEPSEEK_API_ENDPOINT'),
+    }
+  }
+
+  return {
+    provider: 'openrouter' as const,
+    apiKey: nonEmptyString(config.openrouterApiKey, 'OPENROUTER_API_KEY'),
+    model: nonEmptyString(config.openrouterModel || 'deepseek/deepseek-v4-flash', 'OPENROUTER_MODEL'),
+    endpoint: endpoint(config.openrouterApiEndpoint, 'https://openrouter.ai/api/v1/chat/completions', 'OPENROUTER_API_ENDPOINT'),
+  }
+}
+
+export function buildJsonCompletion(config: AiRuntimeConfig, request: JsonCompletionRequest): JsonCompletion {
+  const provider = resolveAiProvider(config)
+  const messages = [{ role: 'system' as const, content: request.system }, ...request.messages]
+  const common = { model: provider.model, messages, stream: false }
+
+  if (provider.provider === 'deepseek') {
+    return {
+      endpoint: provider.endpoint,
+      headers: { Authorization: `Bearer ${provider.apiKey}`, 'Content-Type': 'application/json' },
+      body: {
+        ...common,
+        messages: [
+          { role: 'system' as const, content: `${request.system}\nReturn only valid JSON matching this JSON Schema: ${JSON.stringify(request.jsonSchema)}` },
+          ...request.messages,
+        ],
+        response_format: { type: 'json_object' },
+        thinking: { type: 'disabled' },
+      },
+    }
+  }
+
+  return {
+    endpoint: provider.endpoint,
+    headers: { Authorization: `Bearer ${provider.apiKey}`, 'Content-Type': 'application/json', 'X-Title': 'Dungeons & Ground' },
+    body: {
+      ...common,
+      response_format: { type: 'json_schema', json_schema: { name: request.schemaName, strict: true, schema: request.jsonSchema } },
+      provider: { require_parameters: true, data_collection: 'deny' },
+    },
+  }
+}
+
+export function parseJsonCompletion(payload: unknown): unknown {
+  const completion = CompletionResponseSchema.parse(payload)
+  return JSON.parse(completion.choices[0]!.message.content)
+}