#!/usr/bin/env python3
"""
main.py — App FastAPI : pages statiques (page globale + détail tenant),
API JSON pour les graphiques, et /health pour Kubernetes.
"""

from __future__ import annotations

import sys
from contextlib import asynccontextmanager
from pathlib import Path

sys.path.insert(0, str(Path(__file__).parent))

from fastapi import FastAPI, HTTPException, Query
from fastapi.responses import HTMLResponse
from fastapi.staticfiles import StaticFiles

import queries

FRONTEND_DIR = Path(__file__).parent.parent / "frontend"
PROVIDERS = ("aws", "azure")


@asynccontextmanager
async def lifespan(app: FastAPI):
    queries.init_db()
    yield


app = FastAPI(title="simple-cost-dashboard", lifespan=lifespan)
app.mount("/static", StaticFiles(directory=str(FRONTEND_DIR / "static")), name="static")


def _read_page(filename: str) -> str:
    return (FRONTEND_DIR / filename).read_text()


def _require_provider(provider: str) -> None:
    if provider not in PROVIDERS:
        raise HTTPException(status_code=404, detail=f"Provider inconnu : {provider}")


@app.get("/", response_class=HTMLResponse)
def index_page():
    return _read_page("index.html")


@app.get("/tenant/{provider}/{name}", response_class=HTMLResponse)
def tenant_page(provider: str, name: str):
    _require_provider(provider)
    return _read_page("tenant.html")


@app.get("/health")
def health():
    try:
        conn = queries.get_connection()
        try:
            conn.execute("SELECT 1")
        finally:
            conn.close()
    except Exception as e:
        raise HTTPException(status_code=503, detail=f"Base indisponible : {e}")
    return {"status": "ok"}


@app.get("/api/overview")
def api_overview(months: int = Query(12, ge=1, le=24)):
    conn = queries.get_connection()
    try:
        return queries.overview(conn, months=months)
    finally:
        conn.close()


@app.get("/api/tenant/{provider}/{name}")
def api_tenant_detail(provider: str, name: str, range: int = Query(30, alias="range")):
    _require_provider(provider)
    if range not in (7, 30, 365):
        raise HTTPException(status_code=400, detail="range doit être 7, 30 ou 365")
    conn = queries.get_connection()
    try:
        return queries.tenant_detail(conn, provider, name, range_days=range)
    finally:
        conn.close()


@app.get("/api/tenant/{provider}/{name}/services")
def api_tenant_services_selection(
    provider: str, name: str,
    days: str = Query(None), months: str = Query(None),
):
    _require_provider(provider)
    conn = queries.get_connection()
    try:
        if months:
            selected = [m for m in months.split(",") if m]
            return {"services": queries.services_for_months(conn, provider, name, selected)}
        if days:
            selected = [d for d in days.split(",") if d]
            return {"services": queries.services_for_days(conn, provider, name, selected)}
        raise HTTPException(status_code=400, detail="'days' ou 'months' requis")
    finally:
        conn.close()


@app.get("/api/tenant/{provider}/{name}/resources/{service_name}")
def api_resource_detail(provider: str, name: str, service_name: str):
    _require_provider(provider)
    conn = queries.get_connection()
    try:
        return queries.resource_detail(conn, provider, name, service_name)
    finally:
        conn.close()