Function prepareBuiltInModel

apps/aiagent/fh.ai.js:263–292

(receivingCallback)

    }

    async function prepareBuiltInModel(receivingCallback) {
        if (!isBuiltInPromptSupported()) {
            throw createBuiltInError('当前浏览器不支持 Chrome 内置 AI，请使用 Chrome 138+ 或切换云端服务。');
        }

        const availability = await globalThis.LanguageModel.availability(getBuiltInTextLanguageOptions());
        emitStatus(receivingCallback, availability, undefined, '');

        if (availability === 'unavailable') {
            throw createBuiltInError('当前设备暂不满足 Chrome 内置 AI 运行条件，请切换 SiliconFlow 或自定义服务。');
        }

        let session;
        try {
            session = await globalThis.LanguageModel.create(buildBuiltInCreateOptions({
                initialPrompts: [SYSTEM_PROMPT],
                monitor(monitor) {
                    monitor.addEventListener('downloadprogress', event => {
                        emitStatus(receivingCallback, 'downloading', event.loaded || 0, 'Chrome 正在下载本机 AI 模型。');
                    });
                }
            }));
            emitStatus(receivingCallback, 'available', 1, 'Chrome 内置 AI 已可用。');
            return getBuiltInAvailability();
        } finally {
            if (session && typeof session.destroy === 'function') {
                session.destroy();
            }
        }
    }

    /**
     * 流式问答