from datetime import datetime
from enum import StrEnum

from pydantic import BaseModel, ConfigDict, Field, model_validator


class LeaveType(StrEnum):
    PERSONAL = "PERSONAL"
    SICK = "SICK"
    ANNUAL = "ANNUAL"


class LeaveDraftSuggestionRequest(BaseModel):
    text: str = Field(min_length=1, max_length=2000)
    timezone: str = Field(default="Asia/Shanghai", min_length=1, max_length=64)
    now: datetime | None = None


class LeaveDraftSuggestion(BaseModel):
    type: LeaveType | None = None
    startsAt: datetime | None = None
    endsAt: datetime | None = None
    reason: str | None = Field(default=None, max_length=2000)
    assumptions: list[str] = Field(default_factory=list, max_length=10)
    needsClarification: list[str] = Field(default_factory=list, max_length=10)

    @model_validator(mode="after")
    def validate_time_range(self) -> "LeaveDraftSuggestion":
        if self.startsAt is not None and self.endsAt is not None:
            if self.startsAt.tzinfo is None or self.endsAt.tzinfo is None:
                raise ValueError("startsAt and endsAt must include timezone offsets")
            if self.endsAt <= self.startsAt:
                raise ValueError("endsAt must be later than startsAt")
        if self.reason is not None:
            normalized = self.reason.strip()
            self.reason = normalized or None
        return self


class LeaveDraftSuggestionResponse(BaseModel):
    suggestion: LeaveDraftSuggestion
    model: str
    requiresUserConfirmation: bool = True


class LeaveProgressContext(BaseModel):
    model_config = ConfigDict(extra="forbid")
    requestId: str
    type: LeaveType
    status: str
    startsAt: datetime
    endsAt: datetime
    activeTaskNames: list[str] = Field(default_factory=list, max_length=20)
    completedTaskNames: list[str] = Field(default_factory=list, max_length=50)
    processEnded: bool
    timelineEventTypes: list[str] = Field(default_factory=list, max_length=50)


class LeaveProgressAnswerRequest(BaseModel):
    question: str = Field(min_length=1, max_length=2000)
    timezone: str = Field(min_length=1, max_length=64)
    context: LeaveProgressContext


class LeaveProgressAnswerResponse(BaseModel):
    answer: str = Field(min_length=1, max_length=2000)
    model: str