from flask import Blueprint, request, redirect, flash
from auth import require_level
from config_utils import load_core, save_core, verify_core_hash, apply_msg
import sanitize

bp = Blueprint('action_apply_vlans', __name__)

VIEW   = '/view/view_vlans'


def _row_index():
    try:
        return int(request.form.get('row_index', ''))
    except (ValueError, TypeError):
        return None


def _hash_ok():
    if not verify_core_hash(request.form.get('config_hash', '')):
        flash('Configuration was modified by another session. Please refresh and try again.', 'error')
        return False
    return True


@bp.route('/action/add_vlan', methods=['POST'])
@require_level('administrator')
def add_vlan():
    vlan_id_raw    = request.form.get('vlan_id', '').strip()
    name           = sanitize.name(request.form.get('name', ''))
    interface      = sanitize.interface_name(request.form.get('interface', ''))
    subnet         = sanitize.ip_or_cidr(request.form.get('subnet', ''))
    radius_default  = 'radius_default' in request.form
    mdns_reflection = 'mdns_reflection' in request.form

    if not vlan_id_raw or not name or not interface:
        flash('VLAN ID, name, and interface are required.', 'error')
        return redirect(VIEW)

    try:
        vlan_id = int(vlan_id_raw)
        if not (1 <= vlan_id <= 4094):
            raise ValueError
    except (ValueError, TypeError):
        flash('VLAN ID must be between 1 and 4094.', 'error')
        return redirect(VIEW)

    if not _hash_ok():
        return redirect(VIEW)

    core  = load_core()
    vlans = core.setdefault('vlans', [])

    if any(v.get('vlan_id') == vlan_id for v in vlans):
        flash(f'VLAN {vlan_id} already exists.', 'error')
        return redirect(VIEW)

    vlans.append({
        'vlan_id':         vlan_id,
        'name':            name,
        'interface':       interface,
        'dhcp':            {'subnet': subnet},
        'use_blocklists':  [],
        'radius_default':  radius_default,
        'mdns_reflection': mdns_reflection,
        'reservations':    [],
    })
    save_core(core)

    flash(apply_msg(), 'success')
    return redirect(VIEW)


@bp.route('/action/edit_vlan', methods=['POST'])
@require_level('administrator')
def edit_vlan():
    idx = _row_index()
    if idx is None:
        flash('Invalid request.', 'error')
        return redirect(VIEW)

    name           = sanitize.name(request.form.get('name', ''))
    interface      = sanitize.interface_name(request.form.get('interface', ''))
    subnet         = sanitize.ip_or_cidr(request.form.get('subnet', ''))
    radius_default  = 'radius_default' in request.form
    mdns_reflection = 'mdns_reflection' in request.form

    if not name or not interface:
        flash('Name and interface are required.', 'error')
        return redirect(VIEW)

    if not _hash_ok():
        return redirect(VIEW)

    core  = load_core()
    vlans = core.get('vlans', [])
    if idx < 0 or idx >= len(vlans):
        flash('VLAN not found.', 'error')
        return redirect(VIEW)

    vlans[idx].update({'name': name, 'interface': interface, 'radius_default': radius_default, 'mdns_reflection': mdns_reflection})
    vlans[idx].setdefault('dhcp', {})['subnet'] = subnet
    save_core(core)

    flash(apply_msg(), 'success')
    return redirect(VIEW)


@bp.route('/action/delete_vlan', methods=['POST'])
@require_level('administrator')
def delete_vlan():
    idx = _row_index()
    if idx is None:
        flash('Invalid request.', 'error')
        return redirect(VIEW)

    if not _hash_ok():
        return redirect(VIEW)

    core  = load_core()
    vlans = core.get('vlans', [])
    if idx < 0 or idx >= len(vlans):
        flash('VLAN not found.', 'error')
        return redirect(VIEW)

    removed = vlans.pop(idx)
    save_core(core)

    flash(apply_msg(), 'success')
    return redirect(VIEW)