namespace Aeshnidae.CombatWindow;

/// <summary>
/// Chat / console commands added by this mod.
///
/// ModContainer scans the assembly for [CommandHandler] methods and registers them
/// when the mod is enabled (Meta.json "RegisterCommands": true), then removes them
/// again on Disable. Handlers must be public static and match ACE's CommandHandler
/// delegate exactly: (Session session, params string[] parameters).
///
/// Putting a [CommandCategory("...")] attribute on this class would exclude it from
/// automatic registration, leaving it for ModContainer.RegisterCommandCategory().
/// </summary>
public static class Commands
{
    [CommandHandler("combatwindow", AccessLevel.Player, CommandHandlerFlag.None, -1,
        "The evade and resist window in force, and your chance to land at a given skill gap.",
        "/combatwindow            the terms\n" +
        "/combatwindow <gap>      chance to land and to resist at that gap, e.g. /combatwindow -50")]
    public static void HandleStatus(Session session, params string[] parameters)
    {
        var s = Mod.Settings;
        var sb = new StringBuilder();

        if (!s.Enabled)
        {
            Reply(session, "Combat window: off - retail's curve (slope 0.03, no floor, no ceiling).");
            return;
        }

        sb.AppendLine($"Combat window: evade slope {s.EvadeSlope:0.###} (retail 0.03), land chance clamped {s.MinLandChance:P0}-{s.MaxLandChance:P0}; " +
                      $"resist slope {s.ResistSlope:0.###}, spell land chance clamped {s.MinSpellLandChance:P0}-{s.MaxSpellLandChance:P0}.");

        if (parameters.Length > 0 && int.TryParse(parameters[0], out var gap))
        {
            sb.AppendLine($"  attack {gap:+#;-#;0} over defense: melee/missile lands {s.LandChance(gap, 0, false):P1} (retail {Retail(gap):P1}); " +
                          $"a spell lands {s.LandChance(gap, 0, true):P1} (retail {Retail(gap):P1}).");
        }
        else
        {
            foreach (var g in new[] { -150, -100, -50, 0, 50, 100, 150 })
                sb.AppendLine($"  gap {g,4:+#;-#;0}: lands {s.LandChance(g, 0, false),6:P1}   retail {Retail(g),6:P1}");
        }

        Reply(session, sb.ToString().TrimEnd());
    }

    private static double Retail(int gap) => Math.Clamp(1.0 - 1.0 / (1.0 + Math.Exp(0.03 * gap)), 0, 1);

    [CommandHandler("combatwindow-watch", AccessLevel.Admin, CommandHandlerFlag.None, 0,
        "Write every attack on or by an online player to the server journal, with ACE's numbers (Watch.cs). Console-safe.",
        "/combatwindow-watch <player> [minutes]   watch for that long (default 10)\n" +
        "/combatwindow-watch off                  stop\n" +
        "/combatwindow-watch                      who is being watched")]
    public static void HandleWatch(Session session, params string[] parameters)
    {
        if (parameters.Length == 0)
        {
            Reply(session, Watch.Status);
            return;
        }

        if (parameters.Length == 1 && parameters[0].Equals("off", StringComparison.OrdinalIgnoreCase))
        {
            Watch.Stop();
            Reply(session, "watch stopped");
            return;
        }

        var minutes = 10.0;
        var nameParts = parameters;
        if (parameters.Length > 1 && double.TryParse(parameters[^1], out var m) && m > 0)
        {
            minutes = Math.Min(m, 120);
            nameParts = parameters[..^1];
        }

        var name = string.Join(" ", nameParts).Trim();
        var player = PlayerManager.GetOnlinePlayer(name) ?? PlayerManager.GetOnlinePlayer("+" + name);
        if (player is null)
        {
            Reply(session, $"{name} is not online.");
            return;
        }

        Watch.Start(player, minutes);
        Reply(session, $"{Watch.Status} - lines go to the server journal, prefixed [{Mod.Name}] watch:");
    }

    [CommandHandler("combatwindow-reload", AccessLevel.Admin, CommandHandlerFlag.None, 0,
        "Restart the Aeshnidae.CombatWindow mod, re-reading Settings.json.",
        "/combatwindow-reload")]
    public static void HandleReload(Session session, params string[] parameters)
    {
        var container = Mod.Container;
        if (container is null)
        {
            Reply(session, $"{Mod.Name} is not loaded.");
            return;
        }

        container.Restart();
        Reply(session, $"{Mod.Name} restarted.");
    }

    /// <summary>
    /// The client renders an embedded newline as a music note, so a multi-line
    /// message has to go out as one SendMessage per line.
    /// </summary>
    private static void Reply(Session? session, string message)
    {
        if (session?.Player is null)
        {
            ModManager.Log(message);
            return;
        }

        foreach (var line in (message ?? "").Split('\n'))
        {
            var text = line.TrimEnd('\r');

            if (!string.IsNullOrWhiteSpace(text))
                session.Player.SendMessage(text);
        }
    }
}