"""Phase 13: Operational Alerts — Pydantic schemas."""

from __future__ import annotations

from datetime import datetime
from typing import Any, Dict, List, Optional
from uuid import UUID

from pydantic import BaseModel, Field, field_validator

from app.models.operational_alert import AlertRuleType, AlertSeverity, AlertStatus

VALID_SEVERITIES  = {s.value for s in AlertSeverity}
VALID_STATUSES    = {s.value for s in AlertStatus}
VALID_RULE_TYPES  = {r.value for r in AlertRuleType}


# ── AlertRule schemas ─────────────────────────────────────────────────────────

class AlertRuleCreate(BaseModel):
    name:           str  = Field(..., min_length=1, max_length=300)
    description:    Optional[str] = None
    rule_type:      str
    severity:       str  = "medium"
    config:         Dict[str, Any] = Field(default_factory=dict)
    notify_in_app:  bool = True
    notify_webhook: bool = False
    webhook_id:     Optional[UUID] = None
    cooldown_hours: int  = Field(24, ge=0, le=8760)

    @field_validator("rule_type")
    @classmethod
    def validate_rule_type(cls, v: str) -> str:
        if v not in VALID_RULE_TYPES:
            raise ValueError(f"Invalid rule_type. Valid: {VALID_RULE_TYPES}")
        return v

    @field_validator("severity")
    @classmethod
    def validate_severity(cls, v: str) -> str:
        if v not in VALID_SEVERITIES:
            raise ValueError(f"Invalid severity. Valid: {VALID_SEVERITIES}")
        return v


class AlertRuleUpdate(BaseModel):
    name:           Optional[str]           = Field(None, min_length=1, max_length=300)
    description:    Optional[str]           = None
    severity:       Optional[str]           = None
    is_enabled:     Optional[bool]          = None
    config:         Optional[Dict[str, Any]] = None
    notify_in_app:  Optional[bool]          = None
    notify_webhook: Optional[bool]          = None
    webhook_id:     Optional[UUID]          = None
    cooldown_hours: Optional[int]           = Field(None, ge=0, le=8760)

    @field_validator("severity")
    @classmethod
    def validate_severity(cls, v: Optional[str]) -> Optional[str]:
        if v is not None and v not in VALID_SEVERITIES:
            raise ValueError(f"Invalid severity. Valid: {VALID_SEVERITIES}")
        return v


class AlertRuleOut(BaseModel):
    id:             UUID
    name:           str
    description:    Optional[str] = None
    rule_type:      str
    severity:       str
    is_enabled:     bool
    is_system:      bool
    config:         Dict[str, Any]
    notify_in_app:  bool
    notify_webhook: bool
    webhook_id:     Optional[UUID] = None
    cooldown_hours: int
    created_by:     Optional[UUID] = None
    created_at:     Optional[datetime] = None
    last_fired_at:  Optional[datetime] = None

    class Config:
        from_attributes = True


# ── AlertInstance schemas ─────────────────────────────────────────────────────

class AlertInstanceOut(BaseModel):
    id:              UUID
    rule_id:         Optional[UUID] = None
    rule_name:       str
    rule_type:       str
    severity:        str
    title:           str
    message:         str
    details:         Optional[Dict[str, Any]] = None
    status:          str
    acknowledged_by: Optional[UUID] = None
    acknowledged_at: Optional[datetime] = None
    resolved_at:     Optional[datetime] = None
    created_at:      Optional[datetime] = None

    class Config:
        from_attributes = True


# ── Evaluation result ─────────────────────────────────────────────────────────

class EvaluationResult(BaseModel):
    rules_evaluated: int
    alerts_fired:    int
    alerts:          List[AlertInstanceOut] = Field(default_factory=list)
    duration_seconds: float


# ── Summary ───────────────────────────────────────────────────────────────────

class AlertSummary(BaseModel):
    total_open:          int
    total_acknowledged:  int
    total_resolved:      int
    by_severity:         Dict[str, int]
    by_rule_type:        Dict[str, int]
    recent_alerts:       List[AlertInstanceOut] = Field(default_factory=list)