using Godot;
using Mr.BrickAdventures.Autoloads;
using Mr.BrickAdventures.Progression;

namespace Mr.BrickAdventures.scripts.Events;

/// <summary>
/// Records lifetime statistics on the Profile.
/// </summary>
/// <remarks>
/// Statistics moved to the Profile alongside level progression, because they outlive a Playthrough —
/// see docs/adr/0001-three-progression-scopes.md. <see cref="StatName"/> is a closed set, so a typo is
/// now a compile error rather than a silently invented sixth statistic.
/// </remarks>
public partial class StatisticsEventHandler : Node
{
    public override void _Ready()
    {
        EventBus.Instance.CoinCollected += OnCoinCollected;
        EventBus.Instance.EnemyDefeated += OnEnemyDefeated;
        EventBus.Instance.PlayerDied += OnPlayerDied;
        EventBus.Instance.ChildRescued += OnChildRescued;
    }

    public override void _ExitTree()
    {
        if (EventBus.Instance == null) return;

        EventBus.Instance.CoinCollected -= OnCoinCollected;
        EventBus.Instance.EnemyDefeated -= OnEnemyDefeated;
        EventBus.Instance.PlayerDied -= OnPlayerDied;
        EventBus.Instance.ChildRescued -= OnChildRescued;
    }

    private static void Record(StatName stat, int amount = 1) =>
        ProgressionRoot.Instance?.RecordStat(stat, amount);

    // Record rejects non-positive amounts, so a zero-value coin is skipped rather than throwing.
    private void OnCoinCollected(int amount, Vector2 position)
    {
        if (amount > 0) Record(StatName.CoinsCollected, amount);
    }

    private void OnEnemyDefeated(Node enemy, Vector2 position) => Record(StatName.EnemiesDefeated);

    private void OnPlayerDied(Vector2 position) => Record(StatName.Deaths);

    private void OnChildRescued(Vector2 position) => Record(StatName.ChildrenRescued);

    // LevelsCompleted is recorded by ProgressionService.FinishLevel, not here. It counts completions
    // including Replays — deliberately a different fact from ClearedLevels.Count — and keeping it next
    // to the settlement is what stops the two drifting apart the way the old pair did.
}