init commit for ai feature

Author: eric2788

src/llms/cloudflare-ai.ts

@@ -0,0 +1,59 @@
+import type { LLMProviders, Session } from "~llms";
+
+export default class CloudflareAI implements LLMProviders {
+
+    constructor(
+        private readonly accountId: string,
+        private readonly apiToken: String,
+        private readonly model = '@cf/facebook/bart-large-cnn' // text summarization model
+    ) { }
+
+    async validate(): Promise<void> {
+        const res = await fetch(`https://api.cloudflare.com/client/v4/accounts/${this.accountId}/ai/models/search?per_page=1`, {
+            headers: {
+                Authorization: `Bearer ${this.apiToken}`
+            }
+        })
+        const json = await res.json()
+        if (!json.success) throw new Error('Cloudflare API 验证失败')
+    }
+
+    async prompt(chat: string): Promise<string> {
+        const res = await fetch(`https://api.cloudflare.com/client/v4/accounts/${this.accountId}/ai/run/${this.model}`, {
+            headers: {
+                Authorization: `Bearer ${this.apiToken}`
+            },
+            body: JSON.stringify({ prompt: chat })
+        })
+        const json = await res.json()
+        return json.response
+    }
+
+    async *promptStream(chat: string): AsyncGenerator<string> {
+        const res = await fetch(`https://api.cloudflare.com/client/v4/accounts/${this.accountId}/ai/run/${this.model}`, {
+            headers: {
+                Authorization: `Bearer ${this.apiToken}`
+            },
+            body: JSON.stringify({ prompt: chat, stream: true })
+        })
+        if (!res.body) throw new Error('Cloudflare AI response body is not readable')
+        const reader = res.body.getReader()
+        const decoder = new TextDecoder('utf-8', { ignoreBOM: true })
+        while (true) {
+            const { done, value } = await reader.read()
+            if (done) break
+            const { response } = JSON.parse(decoder.decode(value, { stream: true }))
+            yield response
+        }
+    }
+
+    async asSession(): Promise<Session<LLMProviders>> {
+        console.warn('Cloudflare AI session is not supported')
+        return {
+            ...this,
+            [Symbol.dispose]: () => { }
+        }
+    }
+
+
+}

src/llms/gemini-nano.ts

@@ -0,0 +1,89 @@
+import type { LLMProviders, Session } from "~llms"
+
+export default class GeminiNano implements LLMProviders {
+
+    async validate(): Promise<void> {
+        if (!window.ai) throw new Error('你的浏览器没有启用 AI 功能')
+        if (!window.ai.languageModel &&
+            !window.ai.assistant &&
+            !window.ai.summarizer
+        ) throw new Error('你的浏览器没有启用 AI 功能')
+    }
+
+    async prompt(chat: string): Promise<string> {
+        using session = await this.asSession()
+        return session.prompt(chat)
+    }
+
+    async *promptStream(chat: string): AsyncGenerator<string> {
+        using session = await this.asSession()
+        return session.promptStream(chat)
+    }
+
+    async asSession(): Promise<Session<LLMProviders>> {
+
+        if (window.ai.assistant || window.ai.languageModel) {
+            const assistant = window.ai.assistant ?? window.ai.languageModel
+            const capabilities = await assistant.capabilities()
+            if (capabilities.available === 'readily') {
+                return new GeminiAssistant(await assistant.create())
+            } else {
+                console.warn('AI Assistant 当前不可用: ', capabilities)
+            }
+        } 
+        
+        if (window.ai.summarizer) {
+            const summarizer = window.ai.summarizer
+            const capabilities = await summarizer.capabilities()
+            if (capabilities.available === 'readily') {
+                return new GeminiSummarizer(await summarizer.create())
+            } else {
+                console.warn('AI Summarizer 当前不可用: ', capabilities)
+            }
+        } 
+
+        throw new Error('你的浏览器 AI 功能当前不可用')
+    }
+}
+
+class GeminiAssistant implements Session<LLMProviders> {
+
+    constructor(private readonly assistant: AIAssistant) { }
+
+    prompt(chat: string): Promise<string> {
+        return this.assistant.prompt(chat)
+    }
+
+    async *promptStream(chat: string): AsyncGenerator<string> {
+        const stream = this.assistant.promptStreaming(chat)
+        for await (const chunk of stream) {
+            yield chunk
+        }
+    }
+
+    [Symbol.dispose](): void {
+        this.assistant.destroy()
+    }
+}
+
+
+class GeminiSummarizer implements Session<LLMProviders> {
+
+    constructor(private readonly summarizer: AISummarizer) { }
+
+    prompt(chat: string): Promise<string> {
+        return this.summarizer.summarize(chat)
+    }
+
+    async *promptStream(chat: string): AsyncGenerator<string> {
+        const stream = this.summarizer.summarizeStreaming(chat)
+        for await (const chunk of stream) {
+            yield chunk
+        }
+    }
+
+    [Symbol.dispose](): void {
+        this.summarizer.destroy()
+    }
+
+}

src/llms/index.ts

@@ -0,0 +1,27 @@
+import cloudflare from './cloudflare-ai'
+import nano from './gemini-nano'
+import worker from './remote-worker'
+
+export interface LLMProviders {
+    validate(): Promise<void>
+    prompt(chat: string): Promise<string>
+    promptStream(chat: string): AsyncGenerator<string>
+    asSession(): Promise<Session<LLMProviders>>
+}
+
+export type Session<T> = Disposable & Omit<T, 'asSession' | 'validate'>
+
+const llms = {
+    cloudflare,
+    nano,
+    worker
+}
+
+export type LLMTypes = keyof typeof llms
+
+export async function createLLMProvider(type: LLMTypes, ...args: any[]): Promise<LLMProviders> {
+    const LLM = llms[type].bind(this, ...args)
+    return new LLM()
+}
+
+export default createLLMProvider

src/llms/remote-worker.ts

@@ -0,0 +1,54 @@
+import type { LLMProviders, Session } from "~llms";
+
+
+// for my worker, so limited usage
+export default class RemoteWorker implements LLMProviders {
+
+    async validate(): Promise<void> {
+        const res = await fetch('https://llm.ericlamm.xyz/status')
+        const json = await res.json()
+        if (json.status !== 'working') {
+            throw new Error('Remote worker is not working')
+        }
+    }
+
+    async prompt(chat: string): Promise<string> {
+        const res = await fetch('https://llm.ericlamm.xyz/', {
+            method: 'POST',
+            headers: {
+                'Content-Type': 'application/json'
+            },
+            body: JSON.stringify({ prompt: chat })
+        })
+        const json = await res.json()
+        return json.response
+    }
+
+    async *promptStream(chat: string): AsyncGenerator<string> {
+        const res = await fetch('https://llm.ericlamm.xyz/', {
+            method: 'POST',
+            headers: {
+                'Content-Type': 'application/json'
+            },
+            body: JSON.stringify({ prompt: chat, stream: true })
+        })
+        if (!res.body) throw new Error('Remote worker response body is not readable')
+        const reader = res.body.getReader()
+        const decoder = new TextDecoder('utf-8', { ignoreBOM: true })
+        while (true) {
+            const { done, value } = await reader.read()
+            if (done) break
+            const { response } = JSON.parse(decoder.decode(value, { stream: true }))
+            yield response
+        }
+    }
+
+    async asSession(): Promise<Session<LLMProviders>> {
+        console.warn('Remote worker session is not supported')
+        return {
+            ...this,
+            [Symbol.dispose]: () => { }
+        }
+    }
+    
+}