app/agents/base.py

from __future__ import annotations

from abc import ABC, abstractmethod
from typing import Any

from app.llm_client import chat_completion_json, safe_json_loads
from app.schemas import AgentResult, Finding
from app.prompts import build_agent_prompt
from app.video_payload import VideoPayload


class BaseAgent(ABC):
    def __init__(self, model: str):
        self.model = model

    @abstractmethod
    def agent_name(self) -> str:
        raise NotImplementedError

    def build_messages(self, video_payload: VideoPayload) -> list[dict[str, Any]]:
        content = [
            {
                "type": "video_url",
                "video_url": {
                    "url": video_payload.value
                },
                "fps": video_payload.fps,
            },
            {
                "type": "text",
                "text": build_agent_prompt(self.agent_name()),
            },
        ]
        return [{"role": "user", "content": content}]

    def run(self, client, video_payload: VideoPayload) -> AgentResult:
        messages = self.build_messages(video_payload)
        raw_text = chat_completion_json(client=client, model=self.model, messages=messages)

        try:
            payload = safe_json_loads(raw_text)
            findings = [Finding(**f) for f in payload.get("findings", [])]
            clip_level_summary = payload.get("clip_level_summary", "")
        except Exception:
            findings = []
            clip_level_summary = "模型输出解析失败！！！"

        # 这里做的主要是补齐 clip_start_sec / clip_end_sec
        # 当前整段视频输入，没有显式分段，因此先统一设为 0
        # 真正的时间信息我仍然还是以 findings 里的 start_sec / end_sec 为准
        return AgentResult(
            agent_name=self.agent_name(),
            clip_start_sec=0.0,
            clip_end_sec=0.0,
            findings=findings,
            clip_level_summary=clip_level_summary,
            raw_text=raw_text,
        )