using LiteDB;

namespace Campus_live_rewrite.api.dbs
{
    /// <summary>
    /// Website support tickets. A signed-in player opens a ticket (from the Support page bot's
    /// "talk to a real person" flow); staff (dev / mod / owner) see EVERY ticket and can reply,
    /// close and reopen. Stored in its own LiteDB file; checkpointed by DbMaintenance.
    /// </summary>
    public static class SupportDB
    {
        private static readonly LiteDatabase DB =
            new LiteDatabase(Environment.CurrentDirectory + "/Data/DBs/Support.db");

        public static void Checkpoint() => DB.Checkpoint();

        private static ILiteCollection<Ticket> Tickets => DB.GetCollection<Ticket>("tickets");

        static SupportDB()
        {
            Tickets.EnsureIndex(x => x.AccountId);
            Tickets.EnsureIndex(x => x.Status);
        }

        public sealed class TicketMessage
        {
            public ulong FromAccountId { get; set; }
            public string FromName { get; set; } = "";
            public bool Staff { get; set; }
            public string Body { get; set; } = "";
            public DateTime At { get; set; } = DateTime.UtcNow;
        }

        public sealed class Ticket
        {
            public int Id { get; set; }                 // LiteDB auto-increment PK
            public ulong AccountId { get; set; }
            public string Username { get; set; } = "";
            public string Subject { get; set; } = "";
            public string Status { get; set; } = "open"; // "open" | "closed"
            public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
            public DateTime UpdatedAt { get; set; } = DateTime.UtcNow;
            public List<TicketMessage> Messages { get; set; } = new();
        }

        public static Ticket Create(ulong accountId, string username, string subject, string body)
        {
            var t = new Ticket
            {
                AccountId = accountId,
                Username = username,
                Subject = string.IsNullOrWhiteSpace(subject) ? "Support request" : subject,
                Status = "open",
            };
            t.Messages.Add(new TicketMessage { FromAccountId = accountId, FromName = username, Staff = false, Body = body });
            Tickets.Insert(t);   // Id auto-assigned
            return t;
        }

        public static Ticket? Get(int id) => Tickets.FindById(id);

        public static List<Ticket> ForAccount(ulong accountId) =>
            Tickets.Find(x => x.AccountId == accountId).OrderByDescending(x => x.UpdatedAt).ToList();

        public static List<Ticket> All(string? status)
        {
            var rows = status == "open"   ? Tickets.Find(x => x.Status == "open")
                     : status == "closed" ? Tickets.Find(x => x.Status == "closed")
                     : Tickets.FindAll();
            return rows.OrderByDescending(x => x.UpdatedAt).ToList();
        }

        public static bool AddMessage(int id, ulong fromId, string fromName, bool staff, string body)
        {
            var t = Tickets.FindById(id);
            if (t == null) return false;
            t.Messages.Add(new TicketMessage { FromAccountId = fromId, FromName = fromName, Staff = staff, Body = body });
            t.UpdatedAt = DateTime.UtcNow;
            // A reply on a closed ticket reopens it, so nobody's follow-up is lost in a closed thread.
            if (t.Status == "closed") t.Status = "open";
            Tickets.Update(t);
            return true;
        }

        public static bool SetStatus(int id, string status)
        {
            var t = Tickets.FindById(id);
            if (t == null) return false;
            t.Status = status;
            t.UpdatedAt = DateTime.UtcNow;
            Tickets.Update(t);
            return true;
        }

        public static int OpenCount() => Tickets.Count(x => x.Status == "open");
    }
}