using System.Text;

namespace ClaudeDo.Data;

/// <summary>
/// Single source of truth for the text handed to Claude as a task prompt:
/// title + description + the OPEN sub-tasks. Resolved sub-tasks are dropped.
/// Shared by the Worker (real prompt) and the UI (the card's "what Claude gets" preview).
/// </summary>
public static class TaskPromptComposer
{
    public static string Compose(string title, string? description, IEnumerable<(string Title, bool Completed)> subtasks,
        IEnumerable<string>? attachmentPaths = null)
    {
        var sb = new StringBuilder((title ?? "").Trim());

        if (!string.IsNullOrWhiteSpace(description))
            sb.Append("\n\n").Append(description.Trim());

        var open = subtasks?.Where(s => !s.Completed).ToList() ?? new List<(string, bool)>();
        if (open.Count > 0)
        {
            sb.Append("\n\n## Sub-Tasks\n");
            foreach (var s in open)
                sb.Append("- [ ] ").Append(s.Title).Append('\n');
        }

        var paths = attachmentPaths?.ToList();
        if (paths is { Count: > 0 })
        {
            sb.Append("\n\n## Reference files\nThese files were attached to this task as read-only reference (they live outside the repo). Read them as needed:\n");
            foreach (var p in paths)
                sb.Append("- ").Append(p).Append('\n');
        }

        return sb.ToString();
    }
}