using NeonSprawl.Server.Game.PositionState;

namespace NeonSprawl.Server.Game.Skills;

/// <summary>Maps <c>GET /game/players/{{id}}/skill-progression</c> (NEO-37).</summary>
public static class SkillProgressionSnapshotApi
{
    public static WebApplication MapSkillProgressionSnapshotApi(this WebApplication app)
    {
        app.MapGet(
            "/game/players/{id}/skill-progression",
            (string id, IPositionStateStore positions, ISkillDefinitionRegistry registry) =>
            {
                if (!positions.TryGetPosition(id, out _))
                {
                    return Results.NotFound();
                }

                var trimmedId = id.Trim();
                return Results.Json(BuildSnapshot(trimmedId, registry));
            });

        return app;
    }

    internal static SkillProgressionSnapshotResponse BuildSnapshot(
        string playerId,
        ISkillDefinitionRegistry registry)
    {
        var defs = registry.GetDefinitionsInIdOrder();
        var skills = new List<SkillProgressionRowJson>(defs.Count);
        foreach (var d in defs)
        {
            skills.Add(
                new SkillProgressionRowJson
                {
                    Id = d.Id,
                    Xp = 0,
                    Level = 1,
                });
        }

        // Ordinal sort for stable serialization; consumers must index rows by skill id (NEO-37).
        skills.Sort(static (a, b) => string.CompareOrdinal(a.Id, b.Id));

        return new SkillProgressionSnapshotResponse
        {
            PlayerId = playerId,
            Skills = skills,
            SchemaVersion = SkillProgressionSnapshotResponse.CurrentSchemaVersion,
        };
    }
}