"""
DocuLens — Tier & usage API endpoints.

Provides routes for checking usage, listing plans, and managing subscriptions.
"""

import logging
from fastapi import APIRouter, Depends, HTTPException
from middleware import check_rate_limit
from api_usage import (
    get_usage, check_quota, check_feature, get_user_tier,
    TIER_FEATURES, TIER_LIMITS,
)

logger = logging.getLogger(__name__)

tiers_router = APIRouter(tags=["tiers"])


# ---------------------------------------------------------------------------
# Public — plan information
# ---------------------------------------------------------------------------

@tiers_router.get("/api/v1/plans")
async def list_plans():
    """List all available pricing plans and their features."""
    plans = []
    pricing = {
        "free": {"price": 0, "label": "Free"},
        "starter": {"price": 29, "label": "Starter"},
        "pro": {"price": 79, "label": "Pro"},
        "enterprise": {"price": 199, "label": "Enterprise"},
    }
    for tier_id, features in TIER_FEATURES.items():
        p = pricing.get(tier_id, {"price": 0, "label": tier_id})
        plans.append({
            "id": tier_id,
            "name": p["label"],
            "price_monthly": p["price"],
            "features": features,
        })
    return {"plans": plans}


# ---------------------------------------------------------------------------
# Authenticated — user usage & quota
# ---------------------------------------------------------------------------

@tiers_router.get("/api/v1/usage")
async def get_user_usage(
    user_id: str = "",
    api_key: str = Depends(check_rate_limit),
):
    """Get the authenticated user's current month usage and limits."""
    if not user_id:
        raise HTTPException(status_code=400, detail="user_id is required")
    usage = get_usage(user_id)
    return usage


@tiers_router.get("/api/v1/usage/check")
async def check_user_quota(
    user_id: str = "",
    pages: int = 1,
    api_key: str = Depends(check_rate_limit),
):
    """Pre-check whether the user can process the requested number of pages."""
    if not user_id:
        raise HTTPException(status_code=400, detail="user_id is required")
    result = check_quota(user_id, pages)
    if not result["allowed"]:
        raise HTTPException(status_code=429, detail=result["message"])
    return result


@tiers_router.get("/api/v1/usage/features")
async def get_tier_features(
    user_id: str = "",
    api_key: str = Depends(check_rate_limit),
):
    """Get the feature flags for the user's current tier."""
    if not user_id:
        raise HTTPException(status_code=400, detail="user_id is required")
    tier = get_user_tier(user_id)
    features = TIER_FEATURES.get(tier, TIER_FEATURES["free"])
    return {"tier": tier, "features": features}