@model List<UserSyncState>
@{
    ViewData["Title"] = "Sync Status";
    var nextSync = (DateTimeOffset?)ViewBag.NextSyncUtc;
    var lastCycle = (DateTimeOffset?)ViewBag.LastCycleStartedUtc;
    var now = (DateTimeOffset)ViewBag.Now;
}

<div class="card">
    <h1>📊 Sync Status</h1>

    @if (TempData["SyncNowMessage"] is string msg)
    {
        <div style="background: #e8f5e9; border: 1px solid #a5d6a7; border-radius: 6px; padding: 12px 16px; margin-bottom: 16px; color: #2e7d32;">
            @msg
        </div>
    }

    @* ── Global sync schedule ── *@
    <div style="background: #f0f4ff; border-radius: 8px; padding: 16px; margin-bottom: 24px;">
        <div style="display: flex; justify-content: space-between; align-items: center;">
            <h3 style="margin-top: 0; margin-bottom: 0;">⏱ Sync Schedule</h3>
            <div style="display: flex; gap: 8px;">
                <a asp-action="TestExcel" class="btn" style="font-size: 0.85rem; padding: 0.4rem 1rem; background: #ff9800; color: white; text-decoration: none; border-radius: 4px;">
                    🧪 Test Excel
                </a>
                <a asp-action="SyncNow" class="btn btn-primary" style="font-size: 0.85rem; padding: 0.4rem 1rem; text-decoration: none; color: white;">
                    ⚡ Sync Now
                </a>
            </div>
        </div>
        <table style="width: auto;">
            <tr>
                <td><strong>Server time (UTC):</strong></td>
                <td>@now.ToString("yyyy-MM-dd HH:mm:ss") UTC</td>
            </tr>
            <tr>
                <td><strong>Last sync cycle started:</strong></td>
                <td>
                    @if (lastCycle.HasValue)
                    {
                        var ago = now - lastCycle.Value;
                        <span>@lastCycle.Value.ToString("yyyy-MM-dd HH:mm:ss") UTC <em>(@FormatTimeSpan(ago) ago)</em></span>
                    }
                    else
                    {
                        <span>⏳ Not yet run (worker starting up…)</span>
                    }
                </td>
            </tr>
            <tr>
                <td><strong>Next sync cycle at:</strong></td>
                <td>
                    @if (nextSync.HasValue)
                    {
                        var remaining = nextSync.Value - now;
                        if (remaining.TotalSeconds <= 0)
                        {
                            <span>🔄 Running now…</span>
                        }
                        else
                        {
                            <span>@nextSync.Value.ToString("yyyy-MM-dd HH:mm:ss") UTC <em>(in @FormatTimeSpan(remaining))</em></span>
                        }
                    }
                    else
                    {
                        <span>⏳ Worker starting up…</span>
                    }
                </td>
            </tr>
        </table>
    </div>

    @* ── Per-user status table ── *@
    <p>All enrolled users and their current synchronization state.</p>

    @if (Model.Count == 0)
    {
        <p><em>No users enrolled yet.</em></p>
    }
    else
    {
        <table>
            <thead>
                <tr>
                    <th>Status</th>
                    <th>Email</th>
                    <th>User ID</th>
                    <th>Delta Link</th>
                    <th>Last Sync</th>
                    <th>Last Result</th>
                </tr>
            </thead>
            <tbody>
                @foreach (var user in Model)
                {
                    var hasDelta = !string.IsNullOrEmpty(user.LastDeltaLink);
                    var hasError = !string.IsNullOrEmpty(user.LastSyncError);
                    var statusClass = hasError ? "status-error" : hasDelta ? "status-synced" : "status-pending";
                    var statusLabel = hasError ? "Error" : hasDelta ? "Synced" : "Pending";
                    <tr>
                        <td>
                            <span class="status-dot @statusClass"></span>
                            @statusLabel
                        </td>
                        <td>@user.UserEmail</td>
                        <td><code>@user.UserId[..Math.Min(8, user.UserId.Length)]…</code></td>
                        <td>
                            @if (hasDelta)
                            {
                                <span title="@user.LastDeltaLink">✅ Stored (@(user.LastDeltaLink!.Length) chars)</span>
                            }
                            else
                            {
                                <span>⏳ Initial sync pending</span>
                            }
                        </td>
                        <td>
                            @if (user.LastSyncUtc.HasValue)
                            {
                                var syncAgo = now - user.LastSyncUtc.Value;
                                <span title="@user.LastSyncUtc.Value.ToString("o")">
                                    @user.LastSyncUtc.Value.ToString("HH:mm:ss")
                                    <br /><em>(@FormatTimeSpan(syncAgo) ago)</em>
                                </span>
                            }
                            else
                            {
                                <span>—</span>
                            }
                        </td>
                        <td>
                            @if (hasError)
                            {
                                var isTokenError = user.LastSyncError!.Contains("MsalUiRequired") ||
                                                   user.LastSyncError!.Contains("IDW10502") ||
                                                   user.LastSyncError!.Contains("re-authenticate");
                                if (isTokenError)
                                {
                                    <span style="color: #d32f2f;">
                                        🔑 Token expired — <a asp-action="Reauthorize" style="color: #d32f2f; font-weight: bold;">re-authenticate here</a>
                                    </span>
                                }
                                else
                                {
                                    <span style="color: #d32f2f;" title="@user.LastSyncError">
                                        ❌ @(user.LastSyncError!.Length > 80 ? user.LastSyncError[..80] + "…" : user.LastSyncError)
                                    </span>
                                }
                            }
                            else if (!string.IsNullOrEmpty(user.LastSyncResult))
                            {
                                <span style="color: #2e7d32;">✅ @user.LastSyncResult</span>
                            }
                            else
                            {
                                <span>—</span>
                            }
                        </td>
                    </tr>
                }
            </tbody>
        </table>
    }

    <p style="margin-top: 16px; font-size: 0.85em; color: #888;">
        📝 Detailed sync logs are also written to <strong>CalendarSync.xlsx</strong> in each user's OneDrive root.
    </p>
</div>

@functions {
    static string FormatTimeSpan(TimeSpan ts)
    {
        if (ts.TotalSeconds < 60)
            return $"{(int)ts.TotalSeconds}s";
        if (ts.TotalMinutes < 60)
            return $"{(int)ts.TotalMinutes}m {ts.Seconds}s";
        if (ts.TotalHours < 24)
            return $"{(int)ts.TotalHours}h {ts.Minutes}m";
        return $"{(int)ts.TotalDays}d {ts.Hours}h";
    }
}