"""
app/session.py - 会话状态管理
"""

import uuid
import time
from enum import Enum
from typing import Optional
from app.models import RequirementAnalysis, TestCaseResult, CodeGenerationResult


class SessionStatus(str, Enum):
    CLARIFYING = "clarifying"      # 正在澄清需求
    PM_READY   = "pm_ready"        # 需求澄清完毕，可运行 PM Agent
    PM_DONE    = "pm_done"         # PM Agent 已完成
    QA_READY   = "qa_ready"        # 可运行 QA Agent
    QA_DONE    = "qa_done"         # QA Agent 已完成
    DEV_READY  = "dev_ready"       # 可运行 Dev Agent
    DEV_DONE   = "dev_done"        # Dev Agent 已完成
    TEST_DONE  = "test_done"        # 单元测试执行完成

class Session:
    def __init__(self, session_id: str, raw_requirement: str):
        self.session_id: str = session_id
        self.raw_requirement: str = raw_requirement          # 用户最原始的需求
        self.clarified_requirement: str = raw_requirement   # 经过澄清补充后的完整需求
        self.clarify_history: list[dict] = []               # 澄清对话历史
        self.status: SessionStatus = SessionStatus.CLARIFYING
        self.created_at: float = time.time()
        self.updated_at: float = time.time()

        # 各 Agent 产出
        self.requirement_analysis: Optional[RequirementAnalysis] = None
        self.test_cases: Optional[TestCaseResult] = None
        self.code_generation: Optional[CodeGenerationResult] = None
        self.test_execution: Optional[dict] = None  # pytest 执行结果

    def touch(self):
        self.updated_at = time.time()


class SessionStore:
    _store: dict[str, Session] = {}
    _TTL_SECONDS = 7200  # 2小时过期

    @classmethod
    def create(cls, raw_requirement: str) -> Session:
        session_id = str(uuid.uuid4())
        session = Session(session_id, raw_requirement)
        cls._store[session_id] = session
        cls._evict_expired()
        return session

    @classmethod
    def get(cls, session_id: str) -> Optional[Session]:
        session = cls._store.get(session_id)
        if session and time.time() - session.updated_at > cls._TTL_SECONDS:
            del cls._store[session_id]
            return None
        return session

    @classmethod
    def _evict_expired(cls):
        now = time.time()
        expired = [sid for sid, s in cls._store.items()
                   if now - s.updated_at > cls._TTL_SECONDS]
        for sid in expired:
            del cls._store[sid]