using MongoDB.Driver;
using QuestionsApi.Models;

namespace QuestionsApi.Services;

public sealed class AccessPurchaseStore
{
    private readonly IMongoCollection<AccessPurchase> _purchases;

    public AccessPurchaseStore(MongoDatabaseProvider mongo)
    {
        _purchases = mongo.Database.GetCollection<AccessPurchase>("AccessPurchases");
        _purchases.Indexes.CreateMany([
            new CreateIndexModel<AccessPurchase>(
                Builders<AccessPurchase>.IndexKeys.Ascending(value => value.UserId).Descending(value => value.CreatedUtc)),
            new CreateIndexModel<AccessPurchase>(
                Builders<AccessPurchase>.IndexKeys.Ascending(value => value.ProviderSessionId),
                new CreateIndexOptions<AccessPurchase>
                {
                    Unique = true,
                    PartialFilterExpression = Builders<AccessPurchase>.Filter.Ne(value => value.ProviderSessionId, "")
                })
        ]);
    }

    public async Task<AccessPurchase> CreateAsync(string userId, AccessProduct product)
    {
        var purchase = new AccessPurchase
        {
            UserId = userId,
            Sku = product.Sku,
            AmountCents = product.AmountCents,
            Currency = product.Currency
        };
        await _purchases.InsertOneAsync(purchase);
        return purchase;
    }

    public async Task<AccessPurchase?> GetOwnedAsync(string id, string userId) =>
        await _purchases.Find(value => value.Id == id && value.UserId == userId).FirstOrDefaultAsync();

    public async Task<AccessPurchase?> GetAsync(string id) =>
        await _purchases.Find(value => value.Id == id).FirstOrDefaultAsync();

    public Task AttachSessionAsync(string id, string sessionId) =>
        _purchases.UpdateOneAsync(
            value => value.Id == id && value.Status == AccessPurchaseStatus.Pending,
            Builders<AccessPurchase>.Update
                .Set(value => value.ProviderSessionId, sessionId)
                .Set(value => value.UpdatedUtc, DateTime.UtcNow));

    public Task MarkCheckoutFailedAsync(string id) =>
        _purchases.UpdateOneAsync(
            value => value.Id == id && value.Status == AccessPurchaseStatus.Pending,
            Builders<AccessPurchase>.Update
                .Set(value => value.Status, AccessPurchaseStatus.Failed)
                .Set(value => value.UpdatedUtc, DateTime.UtcNow));

    public async Task<AccessPurchase?> ApplyProviderStatusAsync(
        string id, string sessionId, long amountCents, string currency,
        string status, string paymentId, string eventId)
    {
        if (string.IsNullOrWhiteSpace(id) || string.IsNullOrWhiteSpace(sessionId)) return null;
        var filters = Builders<AccessPurchase>.Filter;
        var filter = filters.Eq(value => value.Id, id) &
            filters.Eq(value => value.AmountCents, amountCents) &
            filters.Eq(value => value.Currency, currency.ToLowerInvariant()) &
            (filters.Eq(value => value.ProviderSessionId, sessionId) |
             filters.Eq(value => value.ProviderSessionId, "")) &
            filters.Not(filters.AnyEq(value => value.ProviderEventIds, eventId));
        var update = Builders<AccessPurchase>.Update
            .Set(value => value.Status, status)
            .Set(value => value.ProviderSessionId, sessionId)
            .Set(value => value.ProviderPaymentId, paymentId)
            .AddToSet(value => value.ProviderEventIds, eventId)
            .Set(value => value.UpdatedUtc, DateTime.UtcNow);
        return await _purchases.FindOneAndUpdateAsync(filter, update,
            new FindOneAndUpdateOptions<AccessPurchase> { ReturnDocument = ReturnDocument.After });
    }

    public Task MarkGrantAppliedAsync(string id) =>
        _purchases.UpdateOneAsync(
            value => value.Id == id && value.Status == AccessPurchaseStatus.Paid,
            Builders<AccessPurchase>.Update
                .Set(value => value.GrantApplied, true)
                .Set(value => value.UpdatedUtc, DateTime.UtcNow));

    public static AccessPurchaseStatusResponse ToStatus(AccessPurchase purchase) => new()
    {
        PurchaseId = purchase.Id ?? "",
        Sku = purchase.Sku,
        AmountCents = purchase.AmountCents,
        Currency = purchase.Currency,
        Status = purchase.Status
    };
}