import html

from fastapi import APIRouter, Form, Request
from fastapi.responses import HTMLResponse, RedirectResponse

from app.auth import authenticate_user, current_user
from app.templates.layout import page

router = APIRouter()


@router.get("/login", response_class=HTMLResponse)
def login_form(request: Request):
    if current_user(request):
        return RedirectResponse(url="/portal", status_code=303)

    return _render_login()


@router.post("/login", response_class=HTMLResponse)
def login(request: Request, username: str = Form(...), password: str = Form(...)):
    user = authenticate_user(username, password)

    if not user:
        return _render_login("Neplatné přihlašovací údaje.")

    request.session.clear()
    request.session["user_id"] = user["id"]

    return RedirectResponse(url="/portal", status_code=303)


@router.post("/logout")
def logout(request: Request):
    request.session.clear()
    return RedirectResponse(url="/portal/login", status_code=303)


def _render_login(error: str | None = None) -> str:
    error_html = ""
    if error:
        error_html = f'<p class="alert alert-danger">{html.escape(error)}</p>'

    return page(
        "Přihlášení",
        f"""
        <div class="auth-card card">
            <h2>Přihlášení do portálu</h2>
            <p class="muted">Přihlaste se interním účtem AppFactory.</p>
            {error_html}

            <form method="post" action="/portal/login">
                <p>
                    <label>Uživatelské jméno</label><br>
                    <input name="username" autocomplete="username" required autofocus>
                </p>

                <p>
                    <label>Heslo</label><br>
                    <input type="password" name="password" autocomplete="current-password" required>
                </p>

                <button type="submit">Přihlásit</button>
            </form>
        </div>
        """,
    )