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


# ── AI 对话式设计助手（多阶段交互） ──────────────────────────────────


class DesignerStage(StrEnum):
    UNDERSTANDING = "UNDERSTANDING"
    CLARIFYING = "CLARIFYING"
    GENERATING = "GENERATING"
    VALIDATING = "VALIDATING"
    CONFIRMING = "CONFIRMING"


class DesignerFieldType(StrEnum):
    TEXT = "text"
    TEXT_AREA = "textArea"
    SELECT = "select"
    DATE_TIME = "dateTime"
    NUMBER = "number"


class DesignerFormField(BaseModel):
    key: str = Field(min_length=1, max_length=64)
    label: str = Field(min_length=1, max_length=100)
    control: DesignerFieldType
    required: bool = False
    placeholder: str | None = Field(default=None, max_length=200)
    options: list[str] | None = Field(default=None, max_length=20)
    helperText: str | None = Field(default=None, max_length=200)


class DesignerProcessStep(BaseModel):
    name: str = Field(min_length=1, max_length=100)
    assigneeVariable: str = Field(min_length=1, max_length=64)


class DesignerProcessSuggestion(BaseModel):
    mode: str = Field(default="SERIAL", max_length=20)
    steps: list[DesignerProcessStep] = Field(default_factory=list, max_length=10)
    conditionThresholdDays: float | None = None


class SchemaValidationIssue(BaseModel):
    field: str = Field(min_length=1, max_length=100)
    issue: str = Field(min_length=1, max_length=300)
    severity: str = Field(default="WARNING", max_length=20)


class DesignerSuggestion(BaseModel):
    stage: DesignerStage = DesignerStage.UNDERSTANDING
    formTitle: str | None = Field(default=None, max_length=100)
    formKey: str | None = Field(default=None, max_length=64)
    fields: list[DesignerFormField] = Field(default_factory=list, max_length=30)
    process: DesignerProcessSuggestion | None = None
    summary: str = Field(default="", max_length=500)
    understanding: str = Field(default="", max_length=800)
    assumptions: list[str] = Field(default_factory=list, max_length=10)
    needsClarification: list[str] = Field(default_factory=list, max_length=10)
    validationIssues: list[SchemaValidationIssue] = Field(default_factory=list, max_length=20)
    schemaReady: bool = False


class ChatTurn(BaseModel):
    role: str = Field(min_length=1, max_length=20)
    content: str = Field(min_length=1, max_length=4000)


class DesignerSuggestionRequest(BaseModel):
    message: str = Field(min_length=1, max_length=2000)
    history: list[ChatTurn] = Field(default_factory=list, max_length=20)
    currentSchema: str | None = Field(default=None, max_length=8000)
    timezone: str = Field(default="Asia/Shanghai", min_length=1, max_length=64)


class DesignerSuggestionResponse(BaseModel):
    suggestion: DesignerSuggestion
    model: str
    requiresUserConfirmation: bool = True