<?php
header('Content-Type: application/json');
require_once dirname(__DIR__) . '/include/config.php';

if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    echo json_encode(['ok' => false, 'error' => 'Method not allowed']);
    exit;
}

$action = trim($_POST['action'] ?? 'save');

// ── HOST2 pull: pull master.conf from HOST1 via SSH ──────────────────────────────────────────
if ($action === 'pull') {
    $host1Hostname = trim($_POST['host1_hostname'] ?? '');
    $mySlot        = trim($_POST['my_slot'] ?? 'host2');
    $myHostname    = trim($_POST['my_hostname'] ?? '');

    if (!$host1Hostname) {
        echo json_encode(['ok' => false, 'error' => 'HOST1 hostname required']);
        exit;
    }
    if (!preg_match('/^host\d+$/', $mySlot)) {
        echo json_encode(['ok' => false, 'error' => 'Invalid slot']);
        exit;
    }

    $hostId    = strtoupper($mySlot);
    $hostIdLow = strtolower($mySlot);

    // Derive SSH key path from this server's hostname
    $sshOwner = strtolower(preg_replace('/^unraid-/i', '', $myHostname ?: vv_get_hostname()));
    $sshKey   = '/root/.ssh/' . $sshOwner . '_rsync_automation';

    if (!file_exists($sshKey)) {
        echo json_encode(['ok' => false, 'error' =>
            "SSH key not found at $sshKey — run Partnership/ssh_setup.sh first"]);
        exit;
    }

    // Resolve HOST1 Tailscale IP
    $ip = trim(shell_exec('tailscale ip -4 ' . escapeshellarg($host1Hostname) . ' 2>/dev/null') ?: '');
    if (!$ip) {
        echo json_encode(['ok' => false, 'error' =>
            "Cannot resolve Tailscale IP for $host1Hostname — is Tailscale running on both servers?"]);
        exit;
    }

    // Get HOST1's SCRIPTS_DIR from their varaverk.cfg
    $sshBase   = 'ssh -i ' . escapeshellarg($sshKey)
               . ' -o ConnectTimeout=10 -o StrictHostKeyChecking=no root@' . $ip;
    $remoteCfg = trim(shell_exec($sshBase . ' "grep SCRIPTS_DIR /boot/config/plugins/varaverk/varaverk.cfg 2>/dev/null"') ?: '');
    preg_match('/SCRIPTS_DIR\s*=\s*["\']?([^"\']+)["\']?/', $remoteCfg, $sm);
    $remoteConf = rtrim($sm[1] ?? '/mnt/user/appdata/Varaverk', '/') . '/Configurations';

    // SCP master.conf from HOST1
    $localMaster = CONF_DIR . '/master.conf';
    $src  = escapeshellarg('root@' . $ip . ':' . $remoteConf . '/master.conf');
    $cmd  = 'scp -i ' . escapeshellarg($sshKey)
          . ' -o ConnectTimeout=10 -o StrictHostKeyChecking=no'
          . ' ' . $src . ' ' . escapeshellarg($localMaster) . ' 2>&1';
    exec($cmd, $out, $rc);
    if ($rc !== 0) {
        echo json_encode(['ok' => false, 'error' =>
            'SCP failed: ' . implode('; ', $out) .
            ' — ensure your SSH key is authorised on HOST1 (run Partnership/ssh_setup.sh)']);
        exit;
    }

    // Create host conf from template if it doesn't exist
    $confFile = $hostIdLow . '.conf';
    if (!file_exists(CONF_DIR . '/' . $confFile)) {
        $template = @file_get_contents(CONF_DIR . '/host.conf.template') ?: '';
        if ($template) {
            $hostname   = $myHostname ?: vv_get_hostname();
            $sshKeyPath = $sshKey;
            $conf = str_replace('HOSTN', $hostId,    $template);
            $conf = str_replace('hostn', $hostIdLow, $conf);
            $conf = preg_replace('/^(\s*' . $hostId . '_SSH_KEY\s*=\s*)""/m',
                '${1}"' . $sshKeyPath . '"', $conf);
            vv_write_conf_raw($confFile, $conf);
        }
    }

    echo json_encode(['ok' => true, 'host_id' => $hostId, 'conf_file' => $confFile,
                      'redirect' => '?tab=scheduler&vv_setup=' . $confFile]);
    exit;
}

// ── Default action: save (HOST1 first-run wizard) ────────────────────────────────────────────
$host1      = trim($_POST['host1']      ?? '');
$host2      = trim($_POST['host2']      ?? '');
$mySlot     = trim($_POST['my_slot']    ?? 'host1');
$myHostname = trim($_POST['my_hostname'] ?? '');

if (empty($host1)) {
    echo json_encode(['ok' => false, 'error' => 'HOST1 hostname is required']);
    exit;
}
if (!preg_match('/^host\d+$/', $mySlot)) {
    echo json_encode(['ok' => false, 'error' => 'Invalid slot']);
    exit;
}

// Write HOST1 / HOST2 into master.conf
$master = vv_read_conf_raw('master.conf');
if ($master === '') {
    echo json_encode(['ok' => false, 'error' => 'master.conf not found — check SCRIPTS_DIR in varaverk.cfg']);
    exit;
}

$master = preg_replace('/^(\s*HOST1\s*=\s*).*$/m', '${1}"' . addslashes($host1) . '"', $master);
$master = preg_replace('/^(\s*HOST2\s*=\s*).*$/m', '${1}"' . addslashes($host2) . '"', $master);

$slotNum = (int) preg_replace('/\D/', '', $mySlot);
if ($slotNum > 2 && !empty($myHostname)) {
    $hostKey = 'HOST' . $slotNum;
    if (!preg_match('/^\s*' . $hostKey . '\s*=/m', $master)) {
        $master = preg_replace('/^(\s*HOST2\s*=.*$)/m',
            '$1' . "\n    {$hostKey}=\"" . addslashes($myHostname) . '"', $master);
    } else {
        $master = preg_replace('/^(\s*' . $hostKey . '\s*=\s*).*$/m',
            '${1}"' . addslashes($myHostname) . '"', $master);
    }
}

if (!vv_write_conf_raw('master.conf', $master)) {
    echo json_encode(['ok' => false, 'error' => 'Failed to write master.conf']);
    exit;
}

// Create host*.conf from template
$hostId    = strtoupper($mySlot);
$hostIdLow = strtolower($mySlot);
$confFile  = $hostIdLow . '.conf';

if (!file_exists(CONF_DIR . '/' . $confFile)) {
    $template = @file_get_contents(CONF_DIR . '/host.conf.template') ?: '';
    if ($template) {
        $sshOwner   = strtolower(preg_replace('/^unraid-/i', '', $myHostname));
        $sshKeyPath = '/root/.ssh/' . $sshOwner . '_rsync_automation';
        $conf = str_replace('HOSTN', $hostId,    $template);
        $conf = str_replace('hostn', $hostIdLow, $conf);
        $conf = preg_replace('/^(\s*' . $hostId . '_SSH_KEY\s*=\s*)""/m',
            '${1}"' . $sshKeyPath . '"', $conf);
        if (!vv_write_conf_raw($confFile, $conf)) {
            echo json_encode(['ok' => false, 'error' => "Failed to write $confFile"]);
            exit;
        }
    }
}

// Write setup state file — lets partner servers know HOST1 is configured
vv_setup_state_write(['host1_hostname' => $host1]);

echo json_encode([
    'ok'       => true,
    'host_id'  => $hostId,
    'redirect' => '?tab=scheduler&vv_setup=master.conf',
]);