from pathlib import Path
import copy

from flask import Blueprint, request, redirect, flash
from auth import require_level
from config_utils import load_config, record_group, diff_fields, verify_config_hash
import sanitize
import mod_validation as validate

_PAGE = Path(__file__).parent.name

bp = Blueprint(_PAGE, __name__)

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


def _hash_ok():
    if not verify_config_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/hostoverrides/addoverride_add', methods=['POST'])
@require_level('administrator')
def addoverride_add():
    description = sanitize.text(request.form.get('description', ''))
    host        = validate.domainname(request.form.get('host', ''))
    ip          = sanitize.ip(request.form.get('ip', ''))

    if not host or not ip:
        flash('Hostname and IP address are required.', 'error')
        return redirect(f'/{_PAGE}')
    if not _hash_ok():
        return redirect(f'/{_PAGE}')

    cfg = load_config()
    err = validate.check_host_override_ip_in_vlans(ip, cfg)
    if err:
        flash(err, 'error')
        return redirect(f'/{_PAGE}')

    entry = {'description': description, 'host': host, 'ip': ip, 'enabled': True}
    cfg.setdefault('host_overrides', []).append(entry)
    errors = validate.validate_config(cfg)
    if errors:
        for msg in errors:
            flash(msg, 'error')
        return redirect(f'/{_PAGE}')

    changes = diff_fields(None, entry)
    flash(record_group(cfg, 'host_overrides', 'host', host, changes, 'core apply'), 'success')
    return redirect(f'/{_PAGE}')


@bp.route('/action/hostoverrides/table_toggle', methods=['POST'])
@require_level('administrator')
def table_toggle():
    idx = _row_index()
    if idx is None:
        flash('Invalid request.', 'error')
        return redirect(f'/{_PAGE}')
    if not _hash_ok():
        return redirect(f'/{_PAGE}')

    cfg  = load_config()
    items = cfg.get('host_overrides', [])
    if idx < 0 or idx >= len(items):
        flash('Entry not found.', 'error')
        return redirect(f'/{_PAGE}')

    old_enabled        = items[idx].get('enabled', True)
    before             = copy.deepcopy(items[idx])
    items[idx]['enabled'] = not old_enabled
    errors = validate.validate_config(cfg)
    if errors:
        for msg in errors:
            flash(msg, 'error')
        return redirect(f'/{_PAGE}')

    host = items[idx]['host']
    changes = diff_fields(before, items[idx])
    flash(record_group(cfg, 'host_overrides', 'host', host, changes, 'core apply'), 'success')
    return redirect(f'/{_PAGE}')


@bp.route('/action/hostoverrides/table_edit', methods=['POST'])
@require_level('administrator')
def table_edit():
    idx = _row_index()
    if idx is None:
        flash('Invalid request.', 'error')
        return redirect(f'/{_PAGE}')

    description = sanitize.text(request.form.get('description', ''))
    host        = validate.domainname(request.form.get('host', ''))
    ip          = sanitize.ip(request.form.get('ip', ''))
    enabled     = request.form.get('enabled') == 'on'

    if not host or not ip:
        flash('Hostname and IP address are required.', 'error')
        return redirect(f'/{_PAGE}')
    if not _hash_ok():
        return redirect(f'/{_PAGE}')

    cfg = load_config()
    err = validate.check_host_override_ip_in_vlans(ip, cfg)
    if err:
        flash(err, 'error')
        return redirect(f'/{_PAGE}')

    items = cfg.get('host_overrides', [])
    if idx < 0 or idx >= len(items):
        flash('Entry not found.', 'error')
        return redirect(f'/{_PAGE}')

    before = copy.deepcopy(items[idx])
    items[idx].update({'description': description, 'host': host, 'ip': ip, 'enabled': enabled})
    errors = validate.validate_config(cfg)
    if errors:
        for msg in errors:
            flash(msg, 'error')
        return redirect(f'/{_PAGE}')

    changes = diff_fields(before, items[idx])
    flash(record_group(cfg, 'host_overrides', 'host', host, changes, 'core apply'), 'success')
    return redirect(f'/{_PAGE}')


@bp.route('/action/hostoverrides/table_delete', methods=['POST'])
@require_level('administrator')
def table_delete():
    idx = _row_index()
    if idx is None:
        flash('Invalid request.', 'error')
        return redirect(f'/{_PAGE}')
    if not _hash_ok():
        return redirect(f'/{_PAGE}')

    cfg  = load_config()
    items = cfg.get('host_overrides', [])
    if idx < 0 or idx >= len(items):
        flash('Entry not found.', 'error')
        return redirect(f'/{_PAGE}')

    removed = items.pop(idx)
    errors = validate.validate_config(cfg)
    if errors:
        for msg in errors:
            flash(msg, 'error')
        return redirect(f'/{_PAGE}')

    changes = diff_fields(removed, None)
    flash(record_group(cfg, 'host_overrides', 'host', removed['host'], changes, 'core apply'), 'success')
    return redirect(f'/{_PAGE}')