namespace Aeshnidae.Mule;

/// <summary>
/// Two patches. One warms a vault so the first /mule is instant; the other stops ACE's own
/// maintenance from deleting it.
/// </summary>
[HarmonyPatch]
public static class Patches
{
    /// <summary>Purges this mod has refused, for mule-admin and the log.</summary>
    public static int PurgesRefused;

    /// <summary>
    /// Read a vault off disk as its owner logs in, so the first /mule finds it there
    /// rather than being told to try again. The load runs on its own task; this returns
    /// immediately.
    /// </summary>
    [HarmonyPostfix]
    [HarmonyPatch(typeof(Player), nameof(Player.PlayerEnterWorld))]
    public static void AfterEnterWorld(Player __instance)
    {
        try
        {
            var accountId = __instance?.Account?.AccountId ?? 0;

            if (accountId != 0)
                Vault.Warm(accountId);
        }
        catch (Exception ex)
        {
            // Never throw out of a hot-path patch.
            ModManager.Log($"[{Mod.Name}] warming a vault at login failed: {ex.Message}", ModManager.LogLevel.Warn);
        }
    }

    /// <summary>
    /// ACE WOULD DELETE THE VAULT. This stops it.
    ///
    /// `ShardDatabaseOfflineTools.PurgeOrphanedBiotasInParallel` deletes every biota that
    /// has no parent Container, no Wielder and no Location, with one exemption
    /// (WeenieType.Allegiance). A vault container is exactly that: it is in nobody's
    /// inventory, nobody wields it, and it has no position because it is in no landblock.
    /// It would be purged - and on the NEXT run of the same tool every item that had been
    /// in it would be purged too, by the "Parent container not found" pass.
    ///
    /// The tool only runs when `Offline.PurgeOrphanedBiotas` is set in Config.js, it runs
    /// at startup, and its own documentation calls it a once-every-few-months job. That is
    /// precisely the kind of switch that gets flipped a year from now by someone who has
    /// never heard of the vault, so the protection is in code and not in a note:
    /// ModManager.Initialize runs at Program.cs:158 and the purge at :173, so this patch is
    /// in place before the tool can run, and MuleDb has already read every vault container
    /// id out of `aeshnidae_mule` using its own connection (the mod does not need
    /// DatabaseManager, which is not started until :259).
    ///
    /// Giving the containers a dummy Location row would also satisfy the tool, and was
    /// rejected: a biota with a Location in a landblock's range is exactly what
    /// GetDynamicObjectsByLandblock loads when that landblock wakes up, and a vault
    /// appearing on the ground somewhere is worse than the problem.
    /// </summary>
    [HarmonyPrefix]
    [HarmonyPatch(typeof(ACE.Database.ShardDatabaseOfflineTools), nameof(ACE.Database.ShardDatabaseOfflineTools.PurgeBiota),
        new[] { typeof(ACE.Database.Models.Shard.ShardDbContext), typeof(uint), typeof(string) })]
    public static bool BeforePurgeBiota(uint id, string reason, ref bool __result)
    {
        try
        {
            if (!MuleDb.IsVaultContainer(id))
                return true;

            Interlocked.Increment(ref PurgesRefused);

            ModManager.Log($"[{Mod.Name}] REFUSED a purge of 0x{id:X8} - it is an account's vault container (reason given: {reason ?? "none"}). ACE's orphaned-biota pass cannot see that a vault has an owner; aeshnidae_mule can.",
                           ModManager.LogLevel.Warn);

            __result = false;
            return false;
        }
        catch (Exception ex)
        {
            // If the guard itself cannot answer, let ACE through rather than wedging a
            // maintenance tool - but say so loudly, because this is the one patch whose
            // failure can cost an account its gear.
            ModManager.Log($"[{Mod.Name}] the vault purge guard threw on 0x{id:X8} and ACE's purge was NOT blocked: {ex.Message}",
                           ModManager.LogLevel.Error);
            return true;
        }
    }
}