from . import slides_bp
from flask import current_app, abort, redirect, url_for, request, send_from_directory
from app.utils import get_cached_deck_info, token_required
from app.models import Deck, db, Course, PageView
import os
import flask_login
import re


slidev_deck_pattern = re.compile(
    r"^\/slides\/[^\/]+\/[^\/]+\/(?:\d+|index\.html)(?:\?.*)?$"
)
slidev_all_pattern = re.compile(
    r"^\/slides\/([^\/]+)\/([^\/]+)(?:\/presenter)?\/(\d+)(?:\?.*)?$"
)


def log_404(reason: str, deck: str, course: str, path: str, token):
    """
    Helper function to log 404 errors with the user's identity.
    Uses current_app.logger to ensure logs are handled by the app's config.
    """
    user_identity = f"User: {token.name} (ID: {token.id})"
    current_app.logger.warning(
        f"404 Not Found [{reason}] | {user_identity} | Resource: {course}/{deck}/{path}"
    )


@slides_bp.after_request
def inject_confused_button(response):
    if (
        (slidev_deck_pattern.match(request.path) or request.path == "/")
        and response.content_type.startswith("text/html")
        and not flask_login.current_user.is_authenticated
    ):
        if response.direct_passthrough:
            response.direct_passthrough = False
        body = response.get_data(as_text=True)
        insert_at = body.find("</body>")
        if insert_at != -1:
            button_html = """
            <button id="confused-button" style="
                position: fixed;
                bottom: 1.5rem;
                right: 1.5rem;
                z-index: 9999;
                background-color: #4f8cff;
                color: white;
                font-size: 1rem;
                font-weight: bold;
                border: none;
                border-radius: 9999px;
                padding: 1rem;
                box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
                cursor: pointer;
                transition: background-color 0.3s, transform 0.2s;"
                title="Didn't understand? Click!">
              Ich habe das nicht verstanden
            </button>
            <script>
            document.getElementById('confused-button').addEventListener('click', () => {
                fetch('/confused', {method: 'POST'})
                  .then(response => {
                    if (response.ok) {
                      alert('Alles klar! Ich versuche es besser zu erklären. Melde dich, wenn du eine spezifische Frage hast oder noch etwas unklar bleibt.');
                    }
                  }).catch(error => console.error('Error:', error));
            });
            </script>
            """
            body = body[:insert_at] + button_html + body[insert_at:]
            response.set_data(body)
    return response


@slides_bp.route("/<course_folder>/<deck>/")
@slides_bp.route("/<course_folder>/<deck>/<path:path>")
@token_required
def serve_deck(course_folder, deck, token, path="index.html"):
    # 1. Ask the cache for the deck data (0 DB queries on a cache hit!)
    deck_info = get_cached_deck_info(token.id, course_folder, deck)

    # 2. Handle missing data
    if not deck_info["course_exists"]:
        log_404("Course not found", deck, course_folder, path, token)
        abort(404)

    if not deck_info["deck_exists"]:
        log_404("Deck not in database", deck, course_folder, path, token)
        abort(404)

    # 3. Handle authorization
    if not deck_info["auth"]:
        current_app.logger.warning(
            f"Access denied (locked) for user {token.name} -> {deck_info.get('deck_name', deck)}"
        )
        return redirect(url_for("main.index"))

    # 4. Resolve the file path entirely using strings
    slides_dir = os.path.join(current_app.config["SLIDES_DIR"], course_folder)
    deck_path = os.path.join(slides_dir, deck)

    if not os.path.exists(deck_path):
        log_404("Deck directory missing on disk", deck, course_folder, path, token)
        return f"Deck '{deck_info['deck_name']}' not found.", 404

    # 5. Serve the file
    if slidev_all_pattern.match(request.path):
        current_app.logger.info(f"User reloaded in deck {deck_info['deck_name']}")
        return send_from_directory(deck_path, deck_info["index_file"])

    requested_file = os.path.join(deck_path, path)
    if os.path.isfile(requested_file):
        if path == deck_info["index_file"]:
            current_app.logger.info(
                f"User {token.name} accessed deck {deck_info['deck_name']}"
            )
            try:
                pv = PageView(deck_id=deck_info["deck_id"], token_id=token.id)
                db.session.add(pv)
                db.session.commit()
            except Exception as e:
                db.session.rollback()
                current_app.logger.error(f"Failed to log page view: {e}")
        return send_from_directory(deck_path, path)

    log_404("File missing within deck", deck, course_folder, path, token)
    abort(404)


@slides_bp.route("/<course_folder>/<deck>/export")
@token_required
def serve_export(deck, course_folder, token):
    course = db.session.execute(
        db.select(Course).where(Course.folder == course_folder)
    ).scalar()
    if not course:
        log_404("Export: Course not found", deck, course_folder, "", token)
        abort(404)
    assert isinstance(course, Course)

    deck_obj = db.session.execute(
        db.select(Deck).where(Deck.deck == deck, Deck.course_id == course.id)
    ).scalar()
    if not deck_obj:
        log_404("Export: Deck not in database", deck, course_folder, "", token)
        abort(404)
    assert isinstance(deck_obj, Deck)

    if not deck_obj.export_file:
        log_404("Export: Deck has no export_file set", deck, course_folder, "", token)
        abort(404)

    if not token.is_unlocked(deck_obj.deck):
        return redirect(url_for("main.index"))

    exports_dir = os.path.join(current_app.config["EXPORTS_DIR"], course.folder)
    deck_path = os.path.join(exports_dir, deck_obj.deck)
    requested_file = os.path.join(deck_path, deck_obj.export_file)
    if os.path.isfile(requested_file):
        current_app.logger.info(f"User {token.name} exported deck {deck_obj.name}")
        return send_from_directory(deck_path, deck_obj.export_file)

    log_404("Export file missing", deck, course_folder, deck_obj.export_file, token)
    abort(404)