"""Flask frontend application."""
import functools

import httpx
from flask import (
    Flask,
    flash,
    redirect,
    render_template,
    request,
    session,
    url_for,
)

from frontend.app.config import Config

app = Flask(__name__)
app.config.from_object(Config)


# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------

def _backend(path: str) -> str:
    return f"{app.config['BACKEND_URL']}{path}"


def _api(method: str, path: str, *, token: str | None = None, **kwargs):
    headers = kwargs.pop("headers", {})
    if token:
        headers["Authorization"] = f"Bearer {token}"
    return httpx.request(method, _backend(path), headers=headers, timeout=30, **kwargs)


def login_required(view):
    @functools.wraps(view)
    def wrapped(*args, **kwargs):
        if "access_token" not in session:
            return redirect(url_for("login"))
        return view(*args, **kwargs)
    return wrapped


# ---------------------------------------------------------------------------
# Auth routes
# ---------------------------------------------------------------------------

@app.get("/")
def index():
    if "access_token" in session:
        return redirect(url_for("dashboard"))
    return redirect(url_for("login"))


@app.route("/login", methods=["GET", "POST"])
def login():
    if request.method == "POST":
        email = request.form["email"]
        password = request.form["password"]
        resp = _api("POST", "/auth/login", json={"email": email, "password": password})
        if resp.status_code == 200:
            data = resp.json()
            session["access_token"] = data["access_token"]
            session["refresh_token"] = data["refresh_token"]
            return redirect(url_for("dashboard"))
        flash("Invalid email or password.", "error")
    return render_template("login.html")


@app.route("/register", methods=["GET", "POST"])
def register():
    if request.method == "POST":
        email = request.form["email"]
        password = request.form["password"]
        resp = _api("POST", "/auth/register", json={"email": email, "password": password})
        if resp.status_code == 201:
            flash("Account created. Please log in.", "success")
            return redirect(url_for("login"))
        detail = resp.json().get("detail", "Registration failed.")
        flash(detail, "error")
    return render_template("register.html")


@app.get("/logout")
def logout():
    refresh_token = session.get("refresh_token")
    if refresh_token:
        _api("POST", "/auth/logout", json={"refresh_token": refresh_token})
    session.clear()
    return redirect(url_for("login"))


# ---------------------------------------------------------------------------
# Authenticated routes
# ---------------------------------------------------------------------------

@app.get("/dashboard")
@login_required
def dashboard():
    token = session["access_token"]
    resp = _api("GET", "/users/me", token=token)
    user = resp.json() if resp.status_code == 200 else {}
    return render_template("dashboard.html", user=user)


@app.route("/generate", methods=["GET", "POST"])
@login_required
def generate():
    result = None
    error = None
    if request.method == "POST":
        gen_type = request.form.get("type", "text")
        model = request.form.get("model", "").strip()
        prompt = request.form.get("prompt", "").strip()
        token = session["access_token"]

        if gen_type == "text":
            resp = _api("POST", "/generate/text", token=token,
                        json={"model": model, "prompt": prompt})
        elif gen_type == "image":
            resp = _api("POST", "/generate/image", token=token,
                        json={"model": model, "prompt": prompt})
        elif gen_type == "video":
            resp = _api("POST", "/generate/video", token=token,
                        json={"model": model, "prompt": prompt})
        else:
            resp = None

        if resp is not None and resp.status_code == 200:
            result = resp.json()
        else:
            detail = resp.json().get("detail", "Generation failed.") if resp is not None else "Unknown error."
            error = detail

    return render_template("generate.html", result=result, error=error)