refactor: replace LocalOAIEngine with LocalAIEngine

Migrate the legacy `LocalOAIEngine` abstraction to a new, generic `LocalAIEngine` base.
- Move all OpenAI type definitions to `LocalAIEngineTypes` and expose them via the engine index.
- Remove the old `LocalOAIEngine` files (and its test) and replace them with `LocalAIEngine` that defines the abstract API for local inference providers.
- Update the `llamacpp-extension` to extend `LocalAIEngine` instead of `AIEngine`.
- Adjust exports to include the new engine and types, and clean up unused imports.
- Add a new test suite for `LocalAIEngine` ensuring the abstract contract is satisfied.

Author: qnixsynapse

core/src/browser/extensions/engines/AIEngine.ts

@@ -1,223 +1,6 @@
 import { BaseExtension } from '../../extension'
 import { EngineManager } from './EngineManager'
 
-/* AIEngine class types */
-
-export interface chatCompletionRequestMessage {
-  role: 'system' | 'user' | 'assistant' | 'tool'
-  content: string | null | Content[] // Content can be a string OR an array of content parts
-  reasoning?: string | null // Some models return reasoning in completed responses
-  reasoning_content?: string | null // Some models return reasoning in completed responses
-  name?: string
-  tool_calls?: any[] // Simplified tool_call_id?: string
-}
-
-export interface Content {
-  type: 'text' | 'image_url' | 'input_audio'
-  text?: string
-  image_url?: string
-  input_audio?: InputAudio
-}
-
-export interface InputAudio {
-  data: string // Base64 encoded audio data
-  format: 'mp3' | 'wav' | 'ogg' | 'flac' // Add more formats as needed/llama-server seems to support mp3
-}
-
-export interface ToolFunction {
-  name: string // Required: a-z, A-Z, 0-9, _, -, max length 64
-  description?: string
-  parameters?: Record<string, unknown> // JSON Schema object
-  strict?: boolean | null // Defaults to false
-}
-
-export interface Tool {
-  type: 'function' // Currently, only 'function' is supported
-  function: ToolFunction
-}
-
-export interface ToolCallOptions {
-  tools?: Tool[]
-}
-
-// A specific tool choice to force the model to call
-export interface ToolCallSpec {
-  type: 'function'
-  function: {
-    name: string
-  }
-}
-
-// tool_choice may be one of several modes or a specific call
-export type ToolChoice = 'none' | 'auto' | 'required' | ToolCallSpec
-
-export interface chatCompletionRequest {
-  model: string // Model ID, though for local it might be implicit via sessionInfo
-  messages: chatCompletionRequestMessage[]
-  thread_id?: string // Thread/conversation ID for context tracking
-  return_progress?: boolean
-  tools?: Tool[]
-  tool_choice?: ToolChoice
-  // Core sampling parameters
-  temperature?: number | null
-  dynatemp_range?: number | null
-  dynatemp_exponent?: number | null
-  top_k?: number | null
-  top_p?: number | null
-  min_p?: number | null
-  typical_p?: number | null
-  repeat_penalty?: number | null
-  repeat_last_n?: number | null
-  presence_penalty?: number | null
-  frequency_penalty?: number | null
-  dry_multiplier?: number | null
-  dry_base?: number | null
-  dry_allowed_length?: number | null
-  dry_penalty_last_n?: number | null
-  dry_sequence_breakers?: string[] | null
-  xtc_probability?: number | null
-  xtc_threshold?: number | null
-  mirostat?: number | null // 0 = disabled, 1 = Mirostat, 2 = Mirostat 2.0
-  mirostat_tau?: number | null
-  mirostat_eta?: number | null
-
-  n_predict?: number | null
-  n_indent?: number | null
-  n_keep?: number | null
-  stream?: boolean | null
-  stop?: string | string[] | null
-  seed?: number | null // RNG seed
-
-  // Advanced sampling
-  logit_bias?: { [key: string]: number } | null
-  n_probs?: number | null
-  min_keep?: number | null
-  t_max_predict_ms?: number | null
-  image_data?: Array<{ data: string; id: number }> | null
-
-  // Internal/optimization parameters
-  id_slot?: number | null
-  cache_prompt?: boolean | null
-  return_tokens?: boolean | null
-  samplers?: string[] | null
-  timings_per_token?: boolean | null
-  post_sampling_probs?: boolean | null
-  chat_template_kwargs?: chat_template_kdict | null
-}
-
-export interface chat_template_kdict {
-  enable_thinking: false
-}
-
-export interface chatCompletionChunkChoiceDelta {
-  content?: string | null
-  role?: 'system' | 'user' | 'assistant' | 'tool'
-  tool_calls?: any[] // Simplified
-}
-
-export interface chatCompletionChunkChoice {
-  index: number
-  delta: chatCompletionChunkChoiceDelta
-  finish_reason?: 'stop' | 'length' | 'tool_calls' | 'content_filter' | 'function_call' | null
-}
-
-export interface chatCompletionPromptProgress {
-  cache: number
-  processed: number
-  time_ms: number
-  total: number
-}
-
-export interface chatCompletionChunk {
-  id: string
-  object: 'chat.completion.chunk'
-  created: number
-  model: string
-  choices: chatCompletionChunkChoice[]
-  system_fingerprint?: string
-  prompt_progress?: chatCompletionPromptProgress
-}
-
-export interface chatCompletionChoice {
-  index: number
-  message: chatCompletionRequestMessage // Response message
-  finish_reason: 'stop' | 'length' | 'tool_calls' | 'content_filter' | 'function_call'
-  logprobs?: any // Simplified
-}
-
-export interface chatCompletion {
-  id: string
-  object: 'chat.completion'
-  created: number
-  model: string // Model ID used
-  choices: chatCompletionChoice[]
-  usage?: {
-    prompt_tokens: number
-    completion_tokens: number
-    total_tokens: number
-  }
-  system_fingerprint?: string
-}
-// --- End OpenAI types ---
-
-// Shared model metadata
-export interface modelInfo {
-  id: string // e.g. "qwen3-4B" or "org/model/quant"
-  name: string // human‑readable, e.g., "Qwen3 4B Q4_0"
-  quant_type?: string // q4_0 (optional as it might be part of ID or name)
-  providerId: string // e.g. "llama.cpp"
-  port: number
-  sizeBytes: number
-  tags?: string[]
-  path?: string // Absolute path to the model file, if applicable
-  // Additional provider-specific metadata can be added here
-  [key: string]: any
-}
-
-// 1. /list
-export type listResult = modelInfo[]
-
-export interface SessionInfo {
-  pid: number // opaque handle for unload/chat
-  port: number // llama-server output port (corrected from portid)
-  model_id: string //name of the model
-  model_path: string // path of the loaded model
-  is_embedding: boolean
-  api_key: string
-  mmproj_path?: string
-}
-
-export interface UnloadResult {
-  success: boolean
-  error?: string
-}
-
-// 5. /chat
-export interface chatOptions {
-  providerId: string
-  sessionId: string
-  /** Full OpenAI ChatCompletionRequest payload */
-  payload: chatCompletionRequest
-}
-// Output for /chat will be Promise<ChatCompletion> for non-streaming
-// or Promise<AsyncIterable<ChatCompletionChunk>> for streaming
-
-// 7. /import
-export interface ImportOptions {
-  modelPath: string
-  mmprojPath?: string
-  modelSha256?: string
-  modelSize?: number
-  mmprojSha256?: string
-  mmprojSize?: number
-}
-
-export interface importResult {
-  success: boolean
-  modelInfo?: modelInfo
-  error?: string
-}
-
 /**
  * Base AIEngine
  * Applicable to all AI Engines
@@ -240,63 +23,4 @@ export abstract class AIEngine extends BaseExtension {
   registerEngine() {
     EngineManager.instance().register(this)
   }
-
-  /**
-   * Gets model info
-   * @param modelId
-   */
-  abstract get(modelId: string): Promise<modelInfo | undefined>
-
-  /**
-   * Lists available models
-   */
-  abstract list(): Promise<modelInfo[]>
-
-  /**
-   * Loads a model into memory
-   */
-  abstract load(modelId: string, settings?: any): Promise<SessionInfo>
-
-  /**
-   * Unloads a model from memory
-   */
-  abstract unload(sessionId: string): Promise<UnloadResult>
-
-  /**
-   * Sends a chat request to the model
-   */
-  abstract chat(
-    opts: chatCompletionRequest,
-    abortController?: AbortController
-  ): Promise<chatCompletion | AsyncIterable<chatCompletionChunk>>
-
-  /**
-   * Deletes a model
-   */
-  abstract delete(modelId: string): Promise<void>
-
-  /**
-   * Updates a model
-   */
-  abstract update(modelId: string, model: Partial<modelInfo>): Promise<void>
-  /**
-   * Imports a model
-   */
-  abstract import(modelId: string, opts: ImportOptions): Promise<void>
-
-  /**
-   * Aborts an ongoing model import
-   */
-  abstract abortImport(modelId: string): Promise<void>
-
-  /**
-   * Get currently loaded models
-   */
-  abstract getLoadedModels(): Promise<string[]>
-
-  /**
-   * Check if a tool is supported by the model
-   * @param modelId
-   */
-  abstract isToolSupported(modelId: string): Promise<boolean>
 }

core/src/browser/extensions/engines/LocalAIEngine.test.ts

@@ -0,0 +1,69 @@
+import { describe, it, expect, beforeEach, vi } from 'vitest'
+import { LocalAIEngine } from './LocalAIEngine'
+
+class TestLocalAIEngine extends LocalAIEngine {
+  provider = 'test-provider'
+
+  async onUnload(): Promise<void> {}
+
+  async get() {
+    return undefined
+  }
+  async list() {
+    return []
+  }
+  async load() {
+    return {} as any
+  }
+  async unload() {
+    return {} as any
+  }
+  async chat() {
+    return {} as any
+  }
+  async delete() {}
+  async update() {}
+  async import() {}
+  async abortImport() {}
+  async getLoadedModels() {
+    return []
+  }
+  async isToolSupported() {
+    return false
+  }
+}
+
+describe('LocalAIEngine', () => {
+  let engine: TestLocalAIEngine
+
+  beforeEach(() => {
+    engine = new TestLocalAIEngine('', '')
+    vi.clearAllMocks()
+  })
+
+  describe('onLoad', () => {
+    it('should call super.onLoad', async () => {
+      const superOnLoadSpy = vi.spyOn(
+        Object.getPrototypeOf(Object.getPrototypeOf(engine)),
+        'onLoad'
+      )
+
+      await engine.onLoad()
+
+      expect(superOnLoadSpy).toHaveBeenCalled()
+    })
+  })
+
+  describe('abstract requirements', () => {
+    it('should implement provider', () => {
+      expect(engine.provider).toBe('test-provider')
+    })
+
+    it('should implement abstract methods', async () => {
+      expect(await engine.get('id')).toBeUndefined()
+      expect(await engine.list()).toEqual([])
+      expect(await engine.getLoadedModels()).toEqual([])
+      expect(await engine.isToolSupported('id')).toBe(false)
+    })
+  })
+})