using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using PowderCoating.Core.Entities;
using PowderCoating.Infrastructure.Data;
using PowderCoating.Shared.Constants;

namespace PowderCoating.Web.Controllers;

/// <summary>
/// SuperAdmin-only dashboard for inspecting Stripe webhook events logged by
/// <c>StripeWebhookController</c>. Provides filtering, search, and pagination over the
/// <c>StripeWebhookEvents</c> table so platform operators can diagnose failed events, confirm
/// delivery, and view the raw JSON payload Stripe sent. Restricted to SuperAdmin because the raw
/// event payloads may contain sensitive subscription and billing information.
/// </summary>
// Intentional exception: StripeWebhookEvents is a platform infrastructure table (not a business entity); same reasoning as StripeWebhookController. See docs/DATA_ACCESS_ARCHITECTURE.md — Permanent Exceptions.
[Authorize(Policy = AppConstants.Policies.SuperAdminOnly)]
public class StripeEventsController : Controller
{
    private readonly ApplicationDbContext _db;
    private readonly ILogger<StripeEventsController> _logger;

    public StripeEventsController(ApplicationDbContext db, ILogger<StripeEventsController> logger)
    {
        _db = db;
        _logger = logger;
    }

    /// <summary>
    /// Lists Stripe webhook events with optional filtering by event type, status, free-text search
    /// (event ID or error message), and date range. Page size is validated against an allowlist
    /// (25/50/100) to prevent unbounded queries. Summary counts (total, processed, failed, last 24h)
    /// are computed with separate COUNT queries rather than in-memory aggregation so they reflect
    /// the unfiltered totals regardless of the current filter state — this gives operators a quick
    /// health snapshot even when the filter is narrowed. The distinct event-type list for the filter
    /// dropdown is also fetched from the DB so it always reflects what has actually been received
    /// rather than a hardcoded enum.
    /// </summary>
    public async Task<IActionResult> Index(
        string? eventType,
        string? status,
        string? search,
        DateTime? from,
        DateTime? to,
        int page = 1,
        int pageSize = 50)
    {
        pageSize = pageSize is 25 or 50 or 100 ? pageSize : 50;
        page = Math.Max(1, page);

        var query = _db.StripeWebhookEvents.AsNoTracking().AsQueryable();

        if (!string.IsNullOrWhiteSpace(eventType))
            query = query.Where(e => e.EventType == eventType);

        if (!string.IsNullOrWhiteSpace(status) && Enum.TryParse<StripeWebhookEventStatus>(status, out var statusEnum))
            query = query.Where(e => e.Status == statusEnum);

        if (!string.IsNullOrWhiteSpace(search))
            query = query.Where(e => e.EventId.Contains(search) || (e.ErrorMessage != null && e.ErrorMessage.Contains(search)));

        if (from.HasValue)
            query = query.Where(e => e.ReceivedAt >= from.Value.Date);

        if (to.HasValue)
            query = query.Where(e => e.ReceivedAt < to.Value.Date.AddDays(1));

        query = query.OrderByDescending(e => e.ReceivedAt);

        var totalCount = await query.CountAsync();
        var events = await query.Skip((page - 1) * pageSize).Take(pageSize).ToListAsync();

        // Distinct event types for filter dropdown
        var eventTypes = await _db.StripeWebhookEvents.AsNoTracking()
            .Select(e => e.EventType)
            .Where(t => t != string.Empty)
            .Distinct()
            .OrderBy(t => t)
            .ToListAsync();

        // Summary counts
        ViewBag.TotalCount = await _db.StripeWebhookEvents.CountAsync();
        ViewBag.ProcessedCount = await _db.StripeWebhookEvents.CountAsync(e => e.Status == StripeWebhookEventStatus.Processed);
        ViewBag.FailedCount = await _db.StripeWebhookEvents.CountAsync(e => e.Status == StripeWebhookEventStatus.Failed);
        ViewBag.Last24hCount = await _db.StripeWebhookEvents.CountAsync(e => e.ReceivedAt >= DateTime.UtcNow.AddHours(-24));

        ViewBag.EventTypes = eventTypes;
        ViewBag.EventTypeFilter = eventType;
        ViewBag.StatusFilter = status;
        ViewBag.Search = search;
        ViewBag.From = from?.ToString("yyyy-MM-dd");
        ViewBag.To = to?.ToString("yyyy-MM-dd");
        ViewBag.Page = page;
        ViewBag.PageSize = pageSize;
        ViewBag.TotalPages = (int)Math.Ceiling(totalCount / (double)pageSize);
        ViewBag.FilteredCount = totalCount;

        return View(events);
    }

    /// <summary>
    /// Shows the full details of a single Stripe webhook event including the raw JSON payload.
    /// Pretty-prints the JSON using <c>System.Text.Json.JsonDocument</c> for readability; falls
    /// back to the original raw string if parsing fails (e.g. for events logged before JSON
    /// validation was added). Returns 404 for unknown event IDs rather than throwing.
    /// </summary>
    public async Task<IActionResult> Details(long id)
    {
        var evt = await _db.StripeWebhookEvents.AsNoTracking().FirstOrDefaultAsync(e => e.Id == id);
        if (evt == null) return NotFound();

        // Try to format the JSON for display
        string formattedJson = evt.RawJson;
        try
        {
            var doc = System.Text.Json.JsonDocument.Parse(evt.RawJson);
            formattedJson = System.Text.Json.JsonSerializer.Serialize(doc.RootElement,
                new System.Text.Json.JsonSerializerOptions { WriteIndented = true });
        }
        catch { /* keep original if parse fails */ }

        ViewBag.FormattedJson = formattedJson;
        return View(evt);
    }
}