namespace BlueLaminate.EFCore.Entities;

/// <summary>Lifecycle of a CSFloat listing as observed across sweeps.</summary>
public enum ListingStatus
{
    /// <summary>Seen in the most recent sweep that covered it.</summary>
    Active = 0,

    /// <summary>
    /// Previously seen, then absent from a sweep that should have covered it —
    /// i.e. sold or delisted. The disappearance is the signal; we can't tell sold
    /// from delisted with certainty, but <see cref="Listing.LastSeenAt"/> bounds when.
    /// </summary>
    Removed = 1,
}

/// <summary>
/// One active-market listing observed on CSFloat via the official
/// <c>GET /api/v1/listings</c> endpoint. Rows are keyed by CSFloat's own listing
/// id and soft-tracked across sweeps: <see cref="FirstSeenAt"/>/<see cref="LastSeenAt"/>
/// bound the observation window and <see cref="Status"/> flips to
/// <see cref="ListingStatus.Removed"/> when a once-seen listing stops appearing,
/// which approximates a sale/delisting.
///
/// A global sweep returns items that may not be in our catalogue, so
/// <see cref="SkinId"/> is a best-effort nullable link (resolved by
/// def_index + paint_index); the listing stands on its own without it.
/// </summary>
public class Listing
{
    public int Id { get; set; }

    /// <summary>CSFloat's listing id (a snowflake string). Natural key for dedup.</summary>
    public string CsFloatListingId { get; set; } = null!;

    /// <summary>"buy_now" or "auction".</summary>
    public string Type { get; set; } = null!;

    /// <summary>Asking price.</summary>
    public decimal Price { get; set; }

    /// <summary>Currency of <see cref="Price"/>. CSFloat lists in USD.</summary>
    public string Currency { get; set; } = "USD";

    /// <summary>When CSFloat says the listing was created.</summary>
    public DateTimeOffset ListedAt { get; set; }

    // Item identity. Stored directly (not only via the Skin link) so listings for
    // items outside our catalogue are still fully described.
    public int DefIndex { get; set; }
    public int PaintIndex { get; set; }
    public string MarketHashName { get; set; } = null!;
    public string? WearName { get; set; }

    /// <summary>
    /// Exact float, or null for items with no float at all (e.g. Vanilla knives).
    /// Null is deliberately distinct from a genuine 0.0 float; a floatless item
    /// also can't be fingerprinted, so its <see cref="SkinInstanceId"/> stays null.
    /// </summary>
    public decimal? FloatValue { get; set; }
    public int PaintSeed { get; set; }
    public bool IsStatTrak { get; set; }
    public bool IsSouvenir { get; set; }
    public int StickerCount { get; set; }

    public string? SellerSteamId { get; set; }
    public string? InspectLink { get; set; }

    /// <summary>
    /// Steam asset id of the listed copy. Changes on trade, so not a stable
    /// identity — but the discriminator that distinguishes duped copies which
    /// otherwise share an identical fingerprint.
    /// </summary>
    public string? AssetId { get; set; }

    /// <summary>Best-effort catalogue link, resolved by def_index + paint_index. Null if unmatched.</summary>
    public int? SkinId { get; set; }
    public Skin? Skin { get; set; }

    /// <summary>
    /// The wear band this listing belongs to. Unlike <see cref="SkinId"/> this is NOT
    /// best-effort: the catalogue sweep pages one skin+wear band at a time, so the band
    /// is set directly from the sweep unit. Null for whole-skin sweeps (e.g. vanilla
    /// knives with no wear bands).
    /// </summary>
    public int? ConditionId { get; set; }
    public SkinCondition? Condition { get; set; }

    /// <summary>
    /// The physical item (by fingerprint) this listing is for. Many listings over
    /// time roll up to one instance, forming its market-movement history. Nullable
    /// because catalogue-less items can't be fingerprinted to a known skin.
    /// </summary>
    public int? SkinInstanceId { get; set; }
    public SkinInstance? SkinInstance { get; set; }

    // Soft-tracking across sweeps.
    public DateTimeOffset FirstSeenAt { get; set; }
    public DateTimeOffset LastSeenAt { get; set; }
    public ListingStatus Status { get; set; }

    /// <summary>When the listing was marked Removed (absent from a sweep). Null while Active.</summary>
    public DateTimeOffset? RemovedAt { get; set; }
}