"""Manager Gen6 — FinOps v2: 비용 최적화·예산 예측·자원 효율화·태깅"""
import uuid
from datetime import datetime, timedelta
from typing import Any, Dict, List, Optional
from fastapi import APIRouter, HTTPException, Query
from pydantic import BaseModel

router = APIRouter(prefix="/api/finops2", tags=["FinOps v2"])

_budgets: Dict[str, Dict] = {}
_cost_policies: Dict[str, Dict] = {}
_allocations: Dict[str, Dict] = {}

class BudgetCreate(BaseModel):
    name: str; amount: float; period: str = "monthly"  # monthly|quarterly|annual
    category: str = "infra"; owner: str = ""
    alert_threshold: float = 0.8  # 80% 도달 시 알림

class CostPolicy(BaseModel):
    name: str; rule: str; action: str = "alert"  # alert|block|scale_down
    threshold: float; resource_type: str = "compute"

# ── 비용 현황 ────────────────────────────────────────────────────────────────
@router.get("/costs/summary")
async def cost_summary(period: str = "monthly"):
    return {"period": period, "total": 3420000, "currency": "KRW",
            "breakdown": [
                {"category": "compute", "amount": 1820000, "ratio": 53.2},
                {"category": "storage", "amount": 820000, "ratio": 24.0},
                {"category": "network", "amount": 480000, "ratio": 14.0},
                {"category": "license", "amount": 300000, "ratio": 8.8},
            ], "vs_last_period": -5.2, "ts": datetime.utcnow().isoformat()}

@router.get("/costs/trend")
async def cost_trend(months: int = 6):
    import random
    return {"months": months, "trend": [
        {"month": f"2026-{6-i:02d}", "amount": round(random.uniform(3000000, 3800000))}
        for i in range(months)
    ]}

@router.get("/costs/by-resource")
async def cost_by_resource(resource_type: str = "compute"):
    return {"resource_type": resource_type, "resources": [
        {"id": "app-01", "name": "Application Server 01", "cost": 680000, "usage_pct": 71.2, "efficiency": "good"},
        {"id": "app-02", "name": "Application Server 02", "cost": 520000, "usage_pct": 43.1, "efficiency": "poor"},
        {"id": "db-01", "name": "Database Server 01", "cost": 620000, "usage_pct": 82.4, "efficiency": "good"},
    ]}

# ── 예산 관리 ────────────────────────────────────────────────────────────────
@router.post("/budgets")
async def create_budget(budget: BudgetCreate):
    bid = f"BUD-{uuid.uuid4().hex[:8].upper()}"
    _budgets[bid] = {**budget.model_dump(), "id": bid, "spent": 0.0,
                     "created_at": datetime.utcnow().isoformat()}
    return _budgets[bid]

@router.get("/budgets")
async def list_budgets():
    default = [
        {"id": "BUD-2026-01", "name": "2026 인프라 예산", "amount": 50000000, "spent": 20520000,
         "ratio": 41.0, "period": "annual", "status": "on_track"},
    ]
    custom = list(_budgets.values())
    return {"budgets": default + custom, "total": len(default) + len(custom)}

@router.get("/budgets/{bid}/forecast")
async def budget_forecast(bid: str):
    b = _budgets.get(bid)
    return {"budget_id": bid, "forecast_eop": 42000000,
            "projected_ratio": 84.0, "risk": "low",
            "months_remaining": 6, "avg_monthly_spend": 3420000}

# ── 비용 최적화 권고 ─────────────────────────────────────────────────────────
@router.get("/optimizations")
async def optimization_recommendations():
    return {"recommendations": [
        {"id": "OPT-001", "resource": "app-02", "type": "right_sizing",
         "current_spec": "4vCPU/8GB", "recommended": "2vCPU/4GB",
         "monthly_saving": 240000, "risk": "low", "confidence": 0.91},
        {"id": "OPT-002", "resource": "app-03", "type": "shutdown_schedule",
         "detail": "야간·주말 비사용 — 스케줄 종료 권장",
         "monthly_saving": 180000, "risk": "low", "confidence": 0.95},
        {"id": "OPT-003", "resource": "storage-old", "type": "archive",
         "detail": "180일 이상 미접근 데이터 아카이브 권장",
         "monthly_saving": 60000, "risk": "low", "confidence": 0.88},
    ], "total_potential_saving": 480000, "ts": datetime.utcnow().isoformat()}

@router.post("/optimizations/{oid}/apply")
async def apply_optimization(oid: str, auto: bool = False):
    return {"optimization_id": oid, "applied": True, "auto": auto,
            "ts": datetime.utcnow().isoformat(), "estimated_saving": 240000}

# ── 비용 정책 ────────────────────────────────────────────────────────────────
@router.post("/cost-policies")
async def create_cost_policy(policy: CostPolicy):
    pid = f"CPOL-{uuid.uuid4().hex[:8].upper()}"
    _cost_policies[pid] = {**policy.model_dump(), "id": pid, "active": True,
                            "triggered_count": 0, "created_at": datetime.utcnow().isoformat()}
    return _cost_policies[pid]

@router.get("/cost-policies")
async def list_cost_policies():
    return {"policies": list(_cost_policies.values()), "total": len(_cost_policies)}

# ── 태깅 거버넌스 ────────────────────────────────────────────────────────────
@router.get("/tags/compliance")
async def tag_compliance():
    return {"total_resources": 48, "tagged": 41, "untagged": 7,
            "compliance_rate": 85.4,
            "required_tags": ["environment", "owner", "cost_center", "project"],
            "untagged_resources": ["network-fw-01", "backup-storage-02"]}

@router.get("/tags/allocation")
async def cost_allocation_by_tag(tag_key: str = "project"):
    return {"tag_key": tag_key, "allocations": [
        {"tag_value": "guardia", "cost": 2100000, "ratio": 61.4},
        {"tag_value": "zioinfo-web", "cost": 820000, "ratio": 24.0},
        {"tag_value": "shared", "cost": 500000, "ratio": 14.6},
    ]}

@router.get("/health")
async def health():
    return {"status": "ok", "budgets": len(_budgets), "policies": len(_cost_policies)}