# app/routes/broadcast.py
# -----------------------
# Admin-only route for composing and sending push notifications to all
# iOS apps. Uses the existing Notification model and notify() utility —
# broadcasts arrive on the iPad via the standard 60-second poll cycle
# (GET /api/v1/notifications?since=...) and trigger a local banner via
# deliverLocalNotification().  No APNs/FCM required.

import logging
from flask import Blueprint, render_template, request, redirect, url_for, flash
from flask_login import login_required, current_user

from app import db
from app.models.broadcast import Broadcast
from app.models.user import User
from app.models.notification import Notification
from app.utils.decorators import admin_required
from app.utils.audit import log_action, ACTION_CREATE

logger = logging.getLogger(__name__)

bp = Blueprint('broadcast', __name__, url_prefix='/admin/broadcast')

# All roles that can hold an active iOS session
BROADCAST_ROLES = ['inspector', 'external_inspector', 'project_manager',
                   'director', 'admin']

ROLE_LABELS = {
    'inspector':          'Inspectors',
    'external_inspector': 'External Inspectors',
    'project_manager': 'Project Managers',
    'director':        'Directors',
    'admin':           'Admins',
}


@bp.route('/', methods=['GET'])
@login_required
@admin_required
def index():
    """Show the compose form and recent broadcast history."""
    history = (
        Broadcast.query
        .order_by(Broadcast.sent_at.desc())
        .limit(50)
        .all()
    )
    return render_template(
        'admin/broadcast.html',
        history=history,
        roles=BROADCAST_ROLES,
        role_labels=ROLE_LABELS,
    )


@bp.route('/send', methods=['POST'])
@login_required
@admin_required
def send():
    """
    Compose and send a broadcast notification.

    Form fields
    -----------
    title       str   Notification title (required, max 255)
    body        str   Notification body text (required)
    roles[]     list  One or more role keys to target (required)
    """
    title       = (request.form.get('title') or '').strip()
    body        = (request.form.get('body')  or '').strip()
    target_roles = request.form.getlist('roles')

    # ── Validation ─────────────────────────────────────────────────────────
    errors = []
    if not title:
        errors.append('Title is required.')
    elif len(title) > 255:
        errors.append('Title must be 255 characters or fewer.')
    if not body:
        errors.append('Message body is required.')
    elif len(body) > 500:
        errors.append('Message must be 500 characters or fewer.')
    valid_roles = [r for r in target_roles if r in BROADCAST_ROLES]
    if not valid_roles:
        errors.append('Select at least one target role.')

    if errors:
        for e in errors:
            flash(e, 'danger')
        return redirect(url_for('broadcast.index'))

    # ── Find target users (active only) ────────────────────────────────────
    recipients = (
        User.query
        .filter(User.role.in_(valid_roles), User.active == True)  # noqa: E712
        .all()
    )
    if not recipients:
        flash('No active users found for the selected roles.', 'warning')
        return redirect(url_for('broadcast.index'))

    # ── Create Notification rows ────────────────────────────────────────────
    # One row per recipient — the iOS poll picks them up in the next 60s cycle.
    # Using the same Notification model as all other in-app notifications means
    # no iOS code changes are needed: existing deliverLocalNotification() fires
    # a banner, and unreadNotificationCount increments as usual.
    for user in recipients:
        notif = Notification(
            user_id    = user.id,
            title      = title,
            body       = body,
            link       = None,   # broadcasts are informational — no destination page
            event_type = 'admin_broadcast',
            is_read    = False,
        )
        db.session.add(notif)

    # ── Record the broadcast ────────────────────────────────────────────────
    broadcast = Broadcast(
        title           = title,
        body            = body,
        target_roles    = valid_roles,
        sent_by_id      = current_user.id,
        recipient_count = len(recipients),
    )
    db.session.add(broadcast)
    db.session.commit()

    log_action(ACTION_CREATE, 'Broadcast', broadcast.id,
               f'"{title}" → {", ".join(valid_roles)} ({len(recipients)} users)')

    logger.info(
        'BROADCAST | id=%d | title=%r | roles=%s | recipients=%d | by=%s',
        broadcast.id, title, valid_roles, len(recipients), current_user.username,
    )

    flash(
        f'Broadcast sent to {len(recipients)} user(s) across '
        f'{", ".join(ROLE_LABELS[r] for r in valid_roles)}.',
        'success',
    )
    return redirect(url_for('broadcast.index'))