from __future__ import annotations

from datetime import datetime
from typing import Any, List, Optional

from pydantic import BaseModel, Field


class MetricCreate(BaseModel):
    """Create a metric definition with business and technical metadata."""
    metric_code: str = Field(..., description="Internal metric code, unique.")
    metric_name: str = Field(..., description="Display name.")
    metric_aliases: Optional[List[str]] = Field(None, description="Optional alias list.")
    biz_domain: str = Field(..., description="Business domain identifier.")
    biz_desc: Optional[str] = Field(None, description="Business definition.")
    chat_turn_id: Optional[int] = Field(None, description="Source chat turn ID.")
    tech_desc: Optional[str] = Field(None, description="Technical definition.")
    formula_expr: Optional[str] = Field(None, description="Formula expression text.")
    base_sql: str = Field(..., description="Canonical SQL used to compute the metric.")
    time_grain: str = Field(..., description="DAY/HOUR/WEEK/MONTH etc.")
    dim_binding: List[str] = Field(..., description="Dimension columns bound to the metric.")
    update_strategy: str = Field(..., description="FULL/INCR/REALTIME.")
    schedule_id: Optional[int] = Field(None, description="Linked schedule id if any.")
    schedule_type: Optional[int] = Field(None, description="Scheduler type identifier.")
    is_active: bool = Field(True, description="Whether the metric is enabled.")
    created_by: Optional[int] = Field(None, description="Creator user id.")
    updated_by: Optional[int] = Field(None, description="Updater user id.")


class MetricUpdate(BaseModel):
    """Partial update for an existing metric definition."""
    metric_name: Optional[str] = None
    metric_aliases: Optional[List[str]] = None
    biz_domain: Optional[str] = None
    biz_desc: Optional[str] = None
    tech_desc: Optional[str] = None
    formula_expr: Optional[str] = None
    base_sql: Optional[str] = None
    time_grain: Optional[str] = None
    dim_binding: Optional[List[str]] = None
    update_strategy: Optional[str] = None
    schedule_id: Optional[int] = None
    schedule_type: Optional[int] = None
    is_active: Optional[bool] = None
    updated_by: Optional[int] = None


class MetricScheduleCreate(BaseModel):
    """Create a cron-based schedule for a metric."""
    metric_id: int
    cron_expr: str
    enabled: bool = True
    priority: int = 10
    backfill_allowed: bool = True
    max_runtime_sec: Optional[int] = None
    retry_times: int = 0
    owner_team: Optional[str] = None
    owner_user_id: Optional[int] = None


class MetricScheduleUpdate(BaseModel):
    """Update fields of an existing metric schedule."""
    cron_expr: Optional[str] = None
    enabled: Optional[bool] = None
    priority: Optional[int] = None
    backfill_allowed: Optional[bool] = None
    max_runtime_sec: Optional[int] = None
    retry_times: Optional[int] = None
    owner_team: Optional[str] = None
    owner_user_id: Optional[int] = None


class MetricRunTrigger(BaseModel):
    """Trigger a metric run, optionally linking to a chat turn or schedule."""
    metric_id: int
    schedule_id: Optional[int] = None
    source_turn_id: Optional[int] = None
    data_time_from: Optional[datetime] = None
    data_time_to: Optional[datetime] = None
    metric_version: Optional[int] = None
    base_sql_snapshot: Optional[str] = None
    triggered_by: str = Field("API", description="SCHEDULER/MANUAL/API/QA_TURN")
    triggered_at: Optional[datetime] = None


class MetricResultItem(BaseModel):
    """Single metric result row to be persisted."""
    stat_time: datetime
    metric_value: float
    metric_version: Optional[int] = None
    extra_dims: Optional[dict[str, Any]] = None
    load_time: Optional[datetime] = None
    data_version: Optional[int] = None


class MetricResultsWriteRequest(BaseModel):
    """Batch write request for metric results."""
    metric_id: int
    results: List[MetricResultItem]