"""WSGI / ASGI application entrypoint. Gunicorn target stays app:asgi_app.

Routes, caching, validation, and Redis statistics live in the adlist package.
"""
import hashlib
from pathlib import Path
from flask import Flask
from flask_compress import Compress
from flask_limiter import Limiter
from asgiref.wsgi import WsgiToAsgi
import config
from adlist import services, pages, converter, metrics

app = Flask(__name__)
app.config.update(MAX_CONTENT_LENGTH=config.MAX_CONTENT_LENGTH, SECRET_KEY=config.SECRET_KEY)
app.debug = config.FLASK_DEBUG

limiter = Limiter(
    key_func=services.get_client_ip,
    app=app,
    default_limits=[config.RATE_LIMIT_DEFAULT],
    storage_uri=config.REDIS_URL,
)
Compress(app)
app.before_request(services.track_request_data)
app.after_request(services.finalize_response)
app.add_template_filter(services.datetimeformat_filter, "datetimeformat")

# Fingerprinting keeps long-lived cache safe for upgraded CSS / JS assets.
def _asset_revision():
    root = Path(__file__).resolve().parent / "static"
    digest = hashlib.sha256()
    for asset in sorted(root.rglob("*.css")) + sorted(root.rglob("*.js")):
        digest.update(asset.relative_to(root).as_posix().encode("utf-8"))
        digest.update(asset.read_bytes())
    return digest.hexdigest()[:12]

ASSET_REVISION = _asset_revision()

@app.context_processor
def inject_common():
    return {"asset_revision": ASSET_REVISION}

app.add_url_rule("/", "index", pages.index, methods=["GET"])
app.add_url_rule("/favicon.ico", "favicon", pages.favicon, methods=["GET"])
app.add_url_rule("/convert", "convert", limiter.limit(config.RATE_LIMIT_CONVERT)(converter.convert), methods=["GET", "HEAD"])

for name, func in (("stats", metrics.stats), ("stats_json", metrics.stats_json)):
    wrapped = services.basic_auth_required(
        realm=config.STATS_BASIC_AUTH_REALM,
        user=config.STATS_BASIC_AUTH_USER,
        password=config.STATS_BASIC_AUTH_PASS,
    )(func)
    app.add_url_rule("/" + ("stats" if name == "stats" else "stats.json"), name, wrapped, methods=["GET"])

for code in (400, 403, 404, 413, 415, 422, 429, 500, 502):
    app.register_error_handler(code, pages.handle_errors)

# Compatibility: integrations refer to app:app or app:asgi_app.
asgi_app = WsgiToAsgi(app)
convert = converter.convert
stats = metrics.stats
stats_json = metrics.stats_json
redis_client = services.redis_client
cache_headers = converter.cache_headers

if __name__ == "__main__":
    app.run(host=config.BIND_HOST, port=config.BIND_PORT)