<?php
require_once __DIR__ . '/config.php';

// Monitor helpers — docker, GPU, resources, transcode sessions, fallback state.

function vv_docker_containers(): array {
    $out = shell_exec('docker ps --format \'{"name":"{{.Names}}","status":"{{.Status}}","image":"{{.Image}}"}\' 2>/dev/null');
    $containers = [];
    foreach (explode("\n", trim($out ?? '')) as $line) {
        if (!$line) continue;
        $c = json_decode($line, true);
        if ($c) $containers[] = $c;
    }
    return $containers;
}

function vv_docker_stopped(): array {
    $out = shell_exec('docker ps -a --filter "status=exited" --filter "status=created" --format \'{"name":"{{.Names}}","status":"{{.Status}}"}\' 2>/dev/null');
    $containers = [];
    foreach (explode("\n", trim($out ?? '')) as $line) {
        if (!$line) continue;
        $c = json_decode($line, true);
        if ($c) $containers[] = $c;
    }
    return $containers;
}

function vv_gpu_stats(): array {
    $out = shell_exec('nvidia-smi --query-gpu=name,memory.used,memory.total,utilization.gpu,temperature.gpu,power.draw,utilization.encoder,utilization.decoder --format=csv,noheader,nounits 2>/dev/null');
    if (!$out) return ['available' => false];

    $parts = array_map('trim', explode(',', $out));
    $power = is_numeric($parts[5] ?? '') ? round((float)$parts[5], 1) : null;
    return [
        'available'    => true,
        'name'         => $parts[0] ?? '',
        'memory_used'  => (int)($parts[1] ?? 0),
        'memory_total' => (int)($parts[2] ?? 0),
        'utilization'  => (int)($parts[3] ?? 0),
        'temperature'  => (int)($parts[4] ?? 0),
        'power_w'      => $power,
        'enc_pct'      => (int)($parts[6] ?? 0),
        'dec_pct'      => (int)($parts[7] ?? 0),
    ];
}

function vv_gpu_processes(): array {
    $out = shell_exec('nvidia-smi --query-compute-apps=pid,used_gpu_memory,name --format=csv,noheader,nounits 2>/dev/null');
    $procs = [];
    foreach (explode("\n", trim($out ?? '')) as $line) {
        if (!$line) continue;
        $parts = array_map('trim', explode(',', $line));
        $procs[] = [
            'pid'        => $parts[0] ?? '',
            'memory_mb'  => $parts[1] ?? '',
            'name'       => $parts[2] ?? '',
        ];
    }
    return $procs;
}

function vv_system_resources(): array {
    $mem = [];
    foreach (file('/proc/meminfo') ?: [] as $line) {
        if (preg_match('/^(MemTotal|MemAvailable):\s+(\d+)/', $line, $m))
            $mem[$m[1]] = (int)$m[2];
    }
    return [
        'ram_total_mb' => (int)(($mem['MemTotal']     ?? 0) / 1024),
        'ram_free_mb'  => (int)(($mem['MemAvailable'] ?? 0) / 1024),
        'cache'        => vv_df('/mnt/cache'),
    ];
}

function vv_cpu_per_core(): array {
    // Parse /proc/stat — [user, nice, system, idle, iowait, irq, softirq]
    $raw = [];
    foreach (file('/proc/stat') ?: [] as $line) {
        if (!preg_match('/^(cpu\d*)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)\s+(\d+)/', $line, $m)) continue;
        $raw[$m[1]] = [(int)$m[2],(int)$m[3],(int)$m[4],(int)$m[5],(int)$m[6],(int)$m[7],(int)$m[8]];
    }

    $stateFile = '/tmp/vv_cpu_stat.json';
    $prev = file_exists($stateFile) ? (json_decode(file_get_contents($stateFile), true) ?: []) : [];
    file_put_contents($stateFile, json_encode($raw));

    $usage = function(array $c, ?array $p): int {
        if (!$p) return 0;
        $dt = array_sum($c) - array_sum($p);
        $di = ($c[3] + $c[4]) - ($p[3] + $p[4]);
        return $dt > 0 ? max(0, min(100, (int)round((1 - $di / $dt) * 100))) : 0;
    };

    $overall = $usage($raw['cpu'] ?? [], $prev['cpu'] ?? null);
    $cores   = [];
    foreach ($raw as $cpu => $c) {
        if ($cpu === 'cpu') continue;
        $num     = (int)substr($cpu, 3);
        $freqKhz = (int)@file_get_contents("/sys/devices/system/cpu/$cpu/cpufreq/scaling_cur_freq");
        $maxKhz  = (int)@file_get_contents("/sys/devices/system/cpu/$cpu/cpufreq/cpuinfo_max_freq");
        $minKhz  = (int)@file_get_contents("/sys/devices/system/cpu/$cpu/cpufreq/cpuinfo_min_freq");
        $cores[] = [
            'core'      => $num,
            'usage_pct' => $usage($c, $prev[$cpu] ?? null),
            'freq_mhz'  => $freqKhz > 0 ? (int)round($freqKhz / 1000) : 0,
            'max_mhz'   => $maxKhz  > 0 ? (int)round($maxKhz  / 1000) : 0,
            'min_mhz'   => $minKhz  > 0 ? (int)round($minKhz  / 1000) : 0,
        ];
    }
    usort($cores, fn($a, $b) => $a['core'] - $b['core']);
    return ['overall' => $overall, 'cores' => $cores];
}

function vv_memory_breakdown(): array {
    $mem = [];
    foreach (file('/proc/meminfo') ?: [] as $line) {
        if (preg_match('/^(\w+):\s+(\d+)/', $line, $m)) $mem[$m[1]] = (int)$m[2];
    }
    $totalKb = $mem['MemTotal'] ?? 0;

    // ZFS ARC
    $arcKb = 0;
    foreach (@file('/proc/spl/kstat/zfs/arcstats') ?: [] as $line) {
        if (preg_match('/^size\s+\d+\s+(\d+)/', $line, $m)) { $arcKb = (int)($m[1] / 1024); break; }
    }

    // Docker — cgroup v1 then v2
    $dockerKb = 0;
    $cgv1 = '/sys/fs/cgroup/memory/docker/memory.usage_in_bytes';
    if (file_exists($cgv1)) {
        $dockerKb = (int)((float)@file_get_contents($cgv1) / 1024);
    } else {
        foreach (glob('/sys/fs/cgroup/system.slice/docker-*.scope/memory.current') ?: [] as $f) {
            $v = @file_get_contents($f);
            if ($v !== false) $dockerKb += (int)((float)$v / 1024);
        }
    }

    // VM (QEMU/KVM RSS)
    $vmKb = 0;
    foreach (preg_split('/\s+/', trim(shell_exec('ps -C qemu-system-x86_64 -o rss= 2>/dev/null') ?: '')) as $rss) {
        if (is_numeric($rss) && $rss > 0) $vmKb += (int)$rss;
    }

    $freeKb   = max(0, $mem['MemAvailable'] ?? 0);
    $systemKb = max(0, $totalKb - $freeKb - $arcKb - $dockerKb - $vmKb);

    // Top processes by RSS — group same-named procs, take top 5
    $grouped = [];
    $psOut = shell_exec("ps -eo comm,rss --sort=-rss 2>/dev/null | tail -n +2 | head -40") ?: '';
    foreach (explode("\n", trim($psOut)) as $line) {
        $parts = preg_split('/\s+/', trim($line), 2);
        if (count($parts) === 2 && is_numeric($parts[1]) && (int)$parts[1] > 0)
            $grouped[$parts[0]] = ($grouped[$parts[0]] ?? 0) + (int)$parts[1];
    }
    arsort($grouped);
    $topProcs = [];
    foreach (array_slice($grouped, 0, 3, true) as $name => $kb)
        $topProcs[] = ['name' => $name, 'kb' => $kb];

    return [
        'total_kb'  => $totalKb,
        'system_kb' => $systemKb,
        'vm_kb'     => $vmKb,
        'zfs_kb'    => $arcKb,
        'docker_kb' => $dockerKb,
        'free_kb'   => $freeKb,
        'top_procs' => $topProcs,
    ];
}

function vv_df(string $path): array {
    $out = shell_exec("df -BM --output=size,used,avail '$path' 2>/dev/null | tail -1");
    if (!$out) return ['available' => false, 'path' => $path];
    $parts = preg_split('/\s+/', trim($out));
    return [
        'available' => true,
        'path'      => $path,
        'size_mb'   => (int)$parts[0],
        'used_mb'   => (int)$parts[1],
        'free_mb'   => (int)$parts[2],
    ];
}

function vv_network_stats(): array {
    $iface = trim(shell_exec("ip route show default 2>/dev/null | awk 'NR==1{print \$5}'") ?: '');
    if (!$iface) {
        $best = ''; $bestBytes = 0;
        foreach (file('/proc/net/dev') ?: [] as $line) {
            if (!preg_match('/^\s*(\w+):\s+(\d+)/', $line, $m) || $m[1] === 'lo') continue;
            if ((int)$m[2] > $bestBytes) { $bestBytes = (int)$m[2]; $best = $m[1]; }
        }
        $iface = $best;
    }
    if (!$iface) return ['available' => false];

    $rxBytes = $txBytes = 0;
    foreach (file('/proc/net/dev') ?: [] as $line) {
        if (!preg_match('/^\s*' . preg_quote($iface, '/') . ':\s+(.+)$/', $line, $m)) continue;
        $parts   = preg_split('/\s+/', trim($m[1]));
        $rxBytes = (int)($parts[0] ?? 0);
        $txBytes = (int)($parts[8] ?? 0);
        break;
    }

    $stateFile = '/tmp/vv_net_stat.json';
    $now  = ['rx' => $rxBytes, 'tx' => $txBytes, 'ts' => microtime(true)];
    $prev = file_exists($stateFile) ? (json_decode(file_get_contents($stateFile), true) ?: []) : [];
    file_put_contents($stateFile, json_encode($now));

    $rxRate = $txRate = 0;
    if (!empty($prev['ts']) && ($dt = $now['ts'] - $prev['ts']) > 0.1) {
        $rxRate = max(0, (int)(($rxBytes - ($prev['rx'] ?? $rxBytes)) / $dt));
        $txRate = max(0, (int)(($txBytes - ($prev['tx'] ?? $txBytes)) / $dt));
    }

    $speedMbps = (int)@file_get_contents("/sys/class/net/$iface/speed");

    // Local IP — use primary iface
    $localIp = trim(shell_exec(
        "ip -4 addr show " . escapeshellarg($iface) . " 2>/dev/null | awk '/inet /{print \$2}' | cut -d/ -f1 | head -1"
    ) ?: '');

    // External IP — curl ifconfig.me, cached 5 min so we don't hammer it
    $extIpCache = '/tmp/vv_ext_ip.cache';
    $extIp = '';
    if (file_exists($extIpCache) && (time() - filemtime($extIpCache)) < 300) {
        $extIp = trim(file_get_contents($extIpCache) ?: '');
    } else {
        $fetched = trim(shell_exec('curl -sf --max-time 4 https://ifconfig.me 2>/dev/null') ?: '');
        if (preg_match('/^\d+\.\d+\.\d+\.\d+$/', $fetched)) {
            $extIp = $fetched;
            file_put_contents($extIpCache, $extIp);
        }
    }

    // Tailscale IP — use `tailscale ip` CLI (interface name varies: tailscale0, tailscale1, etc.)
    $tsIp = trim(shell_exec('tailscale ip -4 2>/dev/null | head -1') ?: '');

    return [
        'available'  => true,
        'iface'      => $iface,
        'speed_mbps' => $speedMbps > 0 ? $speedMbps : null,
        'rx_bps'     => $rxRate,
        'tx_bps'     => $txRate,
        'local_ip'   => $localIp,
        'ext_ip'     => $extIp,
        'ts_ip'      => $tsIp,
    ];
}

function vv_fallback_state(): array {
    // State file written by fallback.sh
    $stateFile = '/tmp/fallback_state.db';
    if (!file_exists($stateFile)) return ['state' => 'UNKNOWN'];
    $raw = [];
    foreach (file($stateFile) ?: [] as $line) {
        [$k, $v] = array_pad(explode('=', trim($line), 2), 2, '');
        $raw[trim($k)] = trim($v);
    }
    return [
        'state'          => $raw['state']          ?? 'UNKNOWN',
        'failover_start' => $raw['failover_start']  ?? '0',
        'tier2_started'  => $raw['tier2_started']   ?? 'false',
        'tier3_started'  => $raw['tier3_started']   ?? 'false',
        'tier4_started'  => $raw['tier4_started']   ?? 'false',
    ];
}

function vv_transcode_sessions(): array {
    $stateFile = '/tmp/transcode_state.db';
    if (!file_exists($stateFile)) return ['available' => false];

    $raw = [];
    foreach (file($stateFile) ?: [] as $line) {
        [$k, $v] = array_pad(explode('=', trim($line), 2), 2, '');
        $raw[trim($k)] = trim($v);
    }

    $target       = $raw['current_target'] ?? '';
    $lastFlip     = (int)($raw['last_flip_time'] ?? 0);
    $flipCount    = (int)($raw['flip_count_hour'] ?? 0);
    $isRamdisk    = str_contains($target, 'ramdisk');

    // Count active session dirs in both known locations
    $ramdiskPath = '/mnt/ramdisk_transcodes/transcoding-temp';
    $ramSessions = count(glob("$ramdiskPath/*/", GLOB_ONLYDIR) ?: []);

    // SSD path: look for any other transcoding-temp sibling
    $ssdPath     = '';
    $ssdSessions = 0;
    foreach (glob('/mnt/*/transcoding-temp/', GLOB_ONLYDIR) ?: [] as $p) {
        if (!str_contains($p, 'ramdisk')) { $ssdPath = $p; break; }
    }
    if ($ssdPath) $ssdSessions = count(glob($ssdPath . '/*/', GLOB_ONLYDIR) ?: []);

    // Ramdisk disk usage
    $rd = vv_df('/mnt/ramdisk_transcodes');

    return [
        'available'       => true,
        'current_target'  => $target,
        'is_ramdisk'      => $isRamdisk,
        'flip_count_hour' => $flipCount,
        'last_flip_time'  => $lastFlip,
        'last_flip_ago'   => $lastFlip > 0 ? time() - $lastFlip : null,
        'ram_sessions'    => $ramSessions,
        'ssd_sessions'    => $ssdSessions,
        'ramdisk'         => $rd,
    ];
}