namespace BlueLaminate.Core.Tradeups;

/// <summary>
/// The ordered weapon-skin rarity tiers that participate in a 10-input tradeup.
/// The ordinal value IS the tier order: a tradeup consumes 10 inputs of tier T and
/// produces an output at the next tier present in the same collection.
/// <para>
/// Only the six weapon tiers are modelled. The catalogue also carries
/// <c>Contraband</c> (the Howl) and <c>Extraordinary</c> (gloves), and knives are
/// stored as <c>Covert</c>; none of those are weapon tradeup tiers, so
/// <see cref="TryParse"/> reports them as "not a weapon tier" rather than mapping
/// them. See the eligibility rules in <see cref="TradeupGraphBuilder"/>.
/// </para>
/// </summary>
public enum WeaponRarity
{
    Consumer = 1,
    Industrial = 2,
    MilSpec = 3,
    Restricted = 4,
    Classified = 5,
    Covert = 6,
}

public static class WeaponRarityExtensions
{
    /// <summary>
    /// Maps a <c>skins.rarity</c> string literal to its weapon tier.
    /// </summary>
    /// <returns>
    /// <c>true</c> with <paramref name="rarity"/> set when the literal is one of the
    /// six weapon tiers; <c>false</c> for <c>Contraband</c>/<c>Extraordinary</c>
    /// (valid catalogue rarities that are not weapon tradeup tiers).
    /// </returns>
    /// <exception cref="ArgumentException">
    /// The literal is none of the known catalogue rarities. Thrown deliberately so a
    /// catalogue rename surfaces loudly instead of silently dropping a whole tier.
    /// </exception>
    public static bool TryParse(string rarity, out WeaponRarity result)
    {
        switch (rarity)
        {
            case "Consumer Grade":
                result = WeaponRarity.Consumer;
                return true;
            case "Industrial Grade":
                result = WeaponRarity.Industrial;
                return true;
            case "Mil-Spec Grade":
                result = WeaponRarity.MilSpec;
                return true;
            case "Restricted":
                result = WeaponRarity.Restricted;
                return true;
            case "Classified":
                result = WeaponRarity.Classified;
                return true;
            case "Covert":
                result = WeaponRarity.Covert;
                return true;

            // Known, valid catalogue rarities that are not weapon tradeup tiers.
            case "Contraband":     // The Howl
            case "Extraordinary":  // Gloves
                result = default;
                return false;

            default:
                throw new ArgumentException(
                    $"Unknown skin rarity literal '{rarity}'. The catalogue may have renamed a "
                    + "rarity; update WeaponRarityExtensions.TryParse so a tier isn't silently dropped.",
                    nameof(rarity));
        }
    }
}