import json
import os
import config_utils
import factory
from pages.ddns.view import public_ip_info
from pages.dhcpleases.view import live_dhcp_leases

METRICS_FILE = f'{config_utils.CONFIGS_DIR}/.dns-metrics'


def load_dns_metrics():
    empty = {'queries': '-', 'hits': '-', 'hit_rate': '-', 'forwarded': '-',
             'auth': '-', 'tcp_peak': '-', 'updated': '-', 'since': '-', 'servers': []}
    try:
        with open(METRICS_FILE) as f:
            data = json.load(f)
        t    = data.get('totals', {})
        meta = data.get('metadata', {})
        fwd  = t.get('queries_forwarded', 0)
        hits = t.get('queries_answered_locally', 0)
        total = fwd + hits
        return {
            'queries':   f'{total:,}' if total else '-',
            'hits':      f'{hits:,}'  if hits  else '-',
            'hit_rate':  f'{hits / total * 100:.0f}%' if total > 0 else '-',
            'forwarded': f'{fwd:,}'   if fwd   else '-',
            'auth':      f'{t.get("queries_authoritative", 0):,}',
            'tcp_peak':  str(t.get('tcp_hwm', 0)),
            'updated':   meta.get('last_recorded', '-'),
            'since':     meta.get('first_recorded', '-'),
            'servers':   t.get('servers', []),
        }
    except Exception:
        return empty


def count_blocked_today():
    out = factory.run("journalctl -u 'dnsmasq-routlin-*' --since '24 hours ago' --no-pager 2>/dev/null | grep -c ' is 0\\.0\\.0\\.0'")
    return out.strip() or '0'


def count_blocked_domains():
    try:
        total = sum(
            int(factory.run(f'wc -l < "{config_utils.BLOCKLISTS_DIR}/{f}"') or 0)
            for f in os.listdir(config_utils.BLOCKLISTS_DIR) if f.endswith('.con')
        )
        return str(total)
    except Exception:
        return '-'


def bl_last_update():
    try:
        mtime = max(
            os.path.getmtime(f'{config_utils.BLOCKLISTS_DIR}/{f}')
            for f in os.listdir(config_utils.BLOCKLISTS_DIR) if f.endswith('.con')
        )
        return config_utils.fmt_timestamp(int(mtime))
    except Exception:
        return '-'


def collect_tokens(cfg):
    tokens = config_utils.collect_layout_tokens(cfg)
    vlans = cfg.get('vlans', [])
    non_vpn_vlans = [v for v in vlans if not v.get('is_vpn')]
    vlan_names = [v.get('name', '') for v in vlans]
    net = cfg.get('network_interfaces', {})
    dns = cfg.get('upstream_dns', {})
    dns_stats = load_dns_metrics()
    ddns = factory.load_ddns()
    ip_str, domains_sub, last_obtained = public_ip_info(ddns)

    tokens['GENERAL_WAN_INTERFACE']     = str(net.get('wan_interface', '-'))
    tokens['OVERVIEW_VLAN_NAMES']       = ', '.join(vlan_names) or '-'
    tokens['STAT_VLAN_COUNT']           = str(len(non_vpn_vlans))
    tokens['STAT_LEASE_COUNT']          = str(len(live_dhcp_leases()))
    tokens['STAT_BANNED_IP_COUNT']      = str(sum(1 for b in cfg.get('banned_ips', []) if b.get('enabled', True)))
    tokens['STAT_BLOCKLIST_COUNT']      = str(len(cfg.get('dns_blocking', {}).get('blocklists', [])))
    tokens['STAT_BLOCKED_TODAY']        = count_blocked_today()
    tokens['STAT_BLOCKED_DOMAINS']      = count_blocked_domains()
    tokens['STAT_BL_LAST_UPDATE']       = bl_last_update()
    tokens['STAT_UPTIME']               = factory.run('uptime -p') or '-'
    tokens['STAT_NFTABLES_STATUS']      = 'Active' if factory.run('nft list tables 2>/dev/null').strip() else 'Inactive'
    tokens['STAT_PUBLIC_IP']            = ip_str
    tokens['STAT_DDNS_HOSTNAME']        = domains_sub
    tokens['DNS_CACHE_SIZE']            = str(dns.get('cache_size', '-'))
    tokens['OVERVIEW_UPSTREAM_SERVERS'] = ', '.join(dns.get('upstream_servers', [])) or '-'
    tokens['DNS_STAT_QUERIES']          = dns_stats['queries']
    tokens['DNS_STAT_HITS']             = dns_stats['hits']
    tokens['DNS_STAT_HIT_RATE']         = dns_stats['hit_rate']
    tokens['DNS_STAT_FORWARDED']        = dns_stats['forwarded']
    tokens['DNS_STAT_AUTH']             = dns_stats['auth']
    tokens['DNS_STAT_TCP_PEAK']         = dns_stats['tcp_peak']
    tokens['DNS_METRICS_UPDATED']       = dns_stats['updated']
    tokens['DNS_METRICS_SINCE']         = dns_stats['since']
    return tokens