feat: add Azure AI integration with deployment configuration

src/api/providers/azure-ai.ts

@@ -0,0 +1,147 @@
+import { Anthropic } from "@anthropic-ai/sdk"
+import ModelClient from "@azure-rest/ai-inference"
+import { isUnexpected } from "@azure-rest/ai-inference"
+import { AzureKeyCredential } from "@azure/core-auth"
+import {
+  ApiHandlerOptions,
+  ModelInfo,
+  azureAiDefaultModelId,
+  AzureAiModelId,
+  azureAiModels,
+  AzureDeploymentConfig
+} from "../../shared/api"
+import { ApiHandler, SingleCompletionHandler } from "../index"
+import { convertToOpenAiMessages } from "../transform/openai-format"
+import { ApiStream } from "../transform/stream"
+
+export class AzureAiHandler implements ApiHandler, SingleCompletionHandler {
+  private options: ApiHandlerOptions
+  private client: ModelClient
+  
+  constructor(options: ApiHandlerOptions) {
+    this.options = options
+    
+    if (!options.azureAiEndpoint) {
+      throw new Error("Azure AI endpoint is required")
+    }
+    
+    if (!options.azureAiKey) {
+      throw new Error("Azure AI key is required") 
+    }
+
+    this.client = new ModelClient(
+      options.azureAiEndpoint,
+      new AzureKeyCredential(options.azureAiKey)
+    )
+  }
+  
+  private getDeploymentConfig(): AzureDeploymentConfig {
+    const model = this.getModel()
+    const defaultConfig = azureAiModels[model.id].defaultDeployment
+    
+    return {
+      name: this.options.azureAiDeployments?.[model.id]?.name || defaultConfig.name,
+      apiVersion: this.options.azureAiDeployments?.[model.id]?.apiVersion || defaultConfig.apiVersion,
+      modelMeshName: this.options.azureAiDeployments?.[model.id]?.modelMeshName
+    }
+  }
+
+  async *createMessage(systemPrompt: string, messages: Anthropic.Messages.MessageParam[]): ApiStream {
+    const modelInfo = this.getModel().info
+    const chatMessages = [
+      { role: "system", content: systemPrompt },
+      ...convertToOpenAiMessages(messages)
+    ]
+
+    try {
+      const response = await this.client.path("/chat/completions").post({
+        body: {
+          messages: chatMessages,
+          temperature: 0,
+          stream: true,
+          max_tokens: modelInfo.maxTokens
+        }
+      }).asNodeStream()
+
+      const stream = response.body
+      if (!stream) {
+        throw new Error(`Failed to get chat completions with status: ${response.status}`)
+      }
+
+      if (response.status !== 200) {
+        throw new Error(`Failed to get chat completions: ${response.body.error}`)
+      }
+
+      for await (const chunk of stream) {
+        if (chunk.toString() === 'data: [DONE]') {
+          return
+        }
+
+        try {
+          const data = JSON.parse(chunk.toString().replace('data: ', ''))
+          const delta = data.choices[0]?.delta
+          
+          if (delta?.content) {
+            yield {
+              type: "text",
+              text: delta.content
+            }
+          }
+
+          if (data.usage) {
+            yield {
+              type: "usage",
+              inputTokens: data.usage.prompt_tokens || 0,
+              outputTokens: data.usage.completion_tokens || 0
+            }
+          }
+        } catch (e) {
+          // Ignore parse errors from incomplete chunks
+          continue
+        }
+      }
+    } catch (error) {
+      if (error instanceof Error) {
+        if ('status' in error && error.status === 429) {
+          throw new Error("Azure AI rate limit exceeded. Please try again later.")
+        }
+        throw new Error(`Azure AI error: ${error.message}`)
+      }
+      throw error
+    }
+  }
+
+  getModel(): { id: AzureAiModelId; info: ModelInfo } {
+    const modelId = this.options.apiModelId
+    if (modelId && modelId in azureAiModels) {
+      const id = modelId as AzureAiModelId
+      return { id, info: azureAiModels[id] }
+    }
+    return { id: azureAiDefaultModelId, info: azureAiModels[azureAiDefaultModelId] }
+  }
+
+  async completePrompt(prompt: string): Promise<string> {
+    try {
+      const response = await this.client.path("/chat/completions").post({
+        body: {
+          messages: [{ role: "user", content: prompt }],
+          temperature: 0
+        }
+      })
+
+      if (isUnexpected(response)) {
+        throw response.body.error
+      }
+
+      return response.body.choices[0]?.message?.content || ""
+    } catch (error) {
+      if (error instanceof Error) {
+        if ('status' in error && error.status === 429) {
+          throw new Error("Azure AI rate limit exceeded. Please try again later.")
+        }
+        throw new Error(`Azure AI completion error: ${error.message}`)
+      }
+      throw error
+    }
+  }
+}