Playa/hosts/Volcanic.AgenticCore.Telegram/Triggers/JevStates.cs

using System.Globalization;
using System.Text.Json.Nodes;
using Volcanic.AgenticCore.Telegram.Groups;

namespace Volcanic.AgenticCore.Telegram.Triggers;

/// <summary>What Jev is asked: the state for one message or a snooze batch, and each trigger's question.</summary>
public static class JevStates
{
    /// <summary><c>{ group, sender, text, reply_to? }</c>.</summary>
    public static JsonObject Single(GroupMessage message)
    {
        ArgumentNullException.ThrowIfNull(message);
        var state = new JsonObject { ["group"] = message.GroupTitle, ["sender"] = message.Sender, ["text"] = message.Text ?? "" };
        AddReply(state, message);
        return state;
    }

    /// <summary>
    /// <c>{ group, messages: [ { time, sender, text, reply_to? } ] }</c>, split so each state stays under
    /// <paramref name="maxChars"/> characters of JSON (one oversized message still gets a state of its own).
    /// </summary>
    public static IReadOnlyList<JsonObject> Batches(string groupTitle, IReadOnlyList<GroupMessage> messages, TimeZoneInfo zone, int maxChars)
    {
        ArgumentNullException.ThrowIfNull(messages);
        ArgumentNullException.ThrowIfNull(zone);
        var states = new List<JsonObject>();
        JsonArray? current = null;
        var size = 0;
        foreach (var message in messages)
        {
            var item = new JsonObject
            {
                ["time"] = TimeZoneInfo.ConvertTime(message.Time, zone).ToString("yyyy-MM-dd HH:mm", CultureInfo.InvariantCulture),
                ["sender"] = message.Sender,
                ["text"] = message.Text ?? "",
            };
            AddReply(item, message);
            var itemSize = item.ToJsonString().Length + 1;
            if (current is null || (size + itemSize > maxChars && current.Count > 0))
            {
                current = [];
                states.Add(new JsonObject { ["group"] = groupTitle, ["messages"] = current });
                size = groupTitle.Length + 30;
            }
            current.Add(item);
            size += itemSize;
        }
        return states;
    }

    public static JevQuestion Question(string id, Trigger trigger)
    {
        ArgumentNullException.ThrowIfNull(trigger);
        return new JevQuestion(id, trigger.Instructions, trigger.CriteriaTrue, trigger.CriteriaFalse);
    }

    /// <summary>
    /// The trigger's one-message question wrapped for a batch: asked plainly, a batch scores high on loosely related
    /// chatter and lower on the real thing (measured: 0.92 vs 0.99 plain, 0.12 vs 0.99 wrapped).
    /// </summary>
    public static JevQuestion BatchQuestion(string id, Trigger trigger)
    {
        ArgumentNullException.ThrowIfNull(trigger);
        var both = !string.IsNullOrWhiteSpace(trigger.CriteriaTrue) && !string.IsNullOrWhiteSpace(trigger.CriteriaFalse);
        return new JevQuestion(id,
            "Answer yes if at least one message in the batch passes this check: " + trigger.Instructions,
            both ? "At least one message: " + trigger.CriteriaTrue : null,
            both ? "No message does; all are like: " + trigger.CriteriaFalse : null);
    }

    private static void AddReply(JsonObject target, GroupMessage message)
    {
        if (message.ReplyTo is { } reply)
            target["reply_to"] = new JsonObject { ["sender"] = reply.Sender, ["text"] = reply.Text ?? "" };
    }
}