using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using System.Text.Json;
using System.Text.Json.Serialization;
using DorkNet.Server.Auth;
using DorkNet.Server.Data;
using DorkNet.Server.Services;

namespace DorkNet.Server.Controllers.API.Avatar.V4;

/// <summary>
/// api.rec.net/api/avatar/v{2,3,4}/items — list of avatar items the
/// caller has UNLOCKED. The watch's
/// <c>RecNet.Avatars+&lt;DowloadUnlockedAvatarItems&gt;</c> coroutine
/// (Cpp2IL_ISIL/.../Avatars_NestedType__DowloadUnlockedAvatarItems_d__21.txt:149
/// hits <c>"{api/avatar/}v4/items"</c>) parses the result as
/// <c>List&lt;UnlockedAvatarItem&gt;</c>; the wardrobe UI then
/// renders a "buy" button for any item NOT in this list and an
/// "equip" affordance for items that are.
///
/// Wire shape per
/// Cpp2IL_ISIL/.../Avatars_NestedType_UnlockedAvatarItem.txt:186-212:
///   "AvatarItemType" (int — Outfit=0 / HairDye=1, NOT slot-based),
///   "AvatarItemDesc" (string — the item GUID with three empty
///     customizations appended, see below),
///   "PlatformMask"   (int), "FriendlyName"   (string),
///   "Tooltip"        (string), "Rarity" (int).
///
/// IMPORTANT — <c>AvatarItemDesc</c> format: the client passes this
/// string to <c>AvatarItem.FromRecNetString(string)</c>
/// (Cpp2IL_ISIL/.../RecRoom/Avatar/Data/Runtime/AvatarItem.txt:81-257).
/// The desc is <c>String.Split(',')</c> into <c>guid + customization[0..3]</c>
/// — the inner overload then indexes <c>customization[0]</c>,
/// <c>customization[1]</c>, <c>customization[2]</c> and throws
/// <c>ArgumentException</c> at <c>ArraySegment.get_Current</c> if the
/// segment is shorter than 3. Every desc we ship MUST therefore have
/// at least 4 comma-separated parts, so we suffix bare GUIDs with
/// <c>",,,"</c> (three empty customizations).
///
/// CATALOG SOURCE — <c>data/avatar_item_lookup.json</c>. Generated by
/// the manual/CI-only BepInEx patch under
/// <c>tools/AvatarCatalogDumpPatch</c>. That patch reads the watch's bundled
/// <c>AvatarItemWardrobeRuntimeConfig.avatarItemDataLookup</c>
/// SerializedDictionary at boot and writes every (guid, AvatarItemData)
/// pair to JSON. THIS is the authoritative safe list — any GUID NOT
/// in this file throws <c>InvalidOperationException("Missing data
/// for guid …")</c> inside the watch's wardrobe parser, which aborts
/// the entire coroutine on the first bad item and leaves the drawer
/// empty. Items extracted from <c>outfits_assets_*.bundle</c>
/// MonoBehaviours (the older <c>data/wardrobe_items.json</c>) are
/// MASK + SWATCH asset GUIDs, NOT AvatarItem GUIDs, so that file
/// can't be used as a safelist.
///
/// PER-PLAYER ownership: the watch intersects each store tile's
/// <c>AvatarItemDesc</c> against THIS list to flip the buy-button
/// to "Already Owned." Returning the global wardrobe here therefore
/// makes every store item appear owned. We instead intersect the
/// caller's <see cref="AvatarEntity.InventoryJson"/> with the master
/// catalog so the watch sees only items the player actually owns.
/// Anonymous calls return [].
/// </summary>
[ApiController]
public class AvatarItemsController(DorkNetDbContext db, IConfiguration config) : ControllerBase
{
    /// <summary>Master catalog keyed by GUID. Loaded once on first
    /// request from <c>data/avatar_item_lookup.json</c>. Same
    /// lazy-load idiom as before but the catalog itself is now a
    /// dump of the watch's bundled
    /// <c>avatarItemDataLookup</c> instead of the asset-bundle
    /// MonoBehaviour scan in the previous wardrobe_items.json.</summary>
    private static readonly Lazy<CatalogData> _catalog = new(LoadCatalog);

    [HttpGet("api/avatar/v2/items")]
    [HttpGet("api/avatar/v3/items")]
    [HttpGet("api/avatar/v4/items")]
    [Authorize]
    public async Task<ActionResult<List<UnlockedAvatarItemDto>>> Get()
    {
        // Keep this switch as a fast kill-switch, but default it on now that
        // the response is bounded below. The risky path is not the parser
        // itself; it is feeding the 2020 watch too many BrowsableAvatarItem /
        // DynamicAvatarItemImposter rows at once.
        if (!config.GetValue("Avatar:EnableUnlockedItems", true))
            return Ok(new List<UnlockedAvatarItemDto>());

        var maxItems = Math.Clamp(config.GetValue("Avatar:MaxUnlockedItems", 30), 1, 120);
        var maxPerSlot = Math.Clamp(config.GetValue("Avatar:MaxUnlockedItemsPerSlot", 4), 1, 20);

        var pid = this.CurrentPlayerId();
        if (pid is not long me) return Ok(new List<UnlockedAvatarItemDto>());

        var avatar = await db.Avatars
            .Where(a => a.PlayerId == me)
            .Select(a => new { a.InventoryJson, a.OutfitSelections })
            .FirstOrDefaultAsync();

        var owned = ParseInventory(avatar?.InventoryJson);
        var ownedHairDyeSlugs = await db.PlayerInventory
            .Where(i => i.PlayerId == me && i.Quantity > 0)
            .Select(i => i.ItemSlug)
            .ToListAsync();
        var ownedHairDyes = ownedHairDyeSlugs
            .Where(slug => StoreService.TryGetHairDyePayload(slug, out _))
            .Distinct(StringComparer.OrdinalIgnoreCase)
            .ToList();
        if (owned.Count == 0 && ownedHairDyes.Count == 0) return Ok(new List<UnlockedAvatarItemDto>());

        var catalog = _catalog.Value;
        var equipped = ParseEquippedItemGuids(avatar?.OutfitSelections);
        var ordered = owned
            .OrderByDescending(guid => equipped.Contains(guid))
            .ThenBy(guid => catalog.SlotByGuid.TryGetValue(guid, out var slot) ? slot : int.MaxValue)
            .ThenBy(guid => guid, StringComparer.OrdinalIgnoreCase);

        var maxOutfitItems = Math.Max(0, maxItems - ownedHairDyes.Count);
        var perSlot = new Dictionary<int, int>();
        var result = new List<UnlockedAvatarItemDto>(Math.Min(owned.Count, maxItems));
        foreach (var guid in ordered)
        {
            if (result.Count >= maxOutfitItems) break;
            // Intersect against the safelist. Items not in the bundled
            // lookup would crash the watch's wardrobe parser, so they're
            // silently dropped here.
            if (!catalog.Items.TryGetValue(guid, out var item)) continue;

            var slot = catalog.SlotByGuid.TryGetValue(guid, out var value) ? value : -1;
            perSlot.TryGetValue(slot, out var count);
            if (count >= maxPerSlot && !equipped.Contains(guid)) continue;

            perSlot[slot] = count + 1;
            result.Add(item);
            if (result.Count >= maxItems) break;
        }

        foreach (var slug in ownedHairDyes)
        {
            if (result.Count >= maxItems) break;
            if (!StoreService.TryGetHairDyePayload(slug, out var hairColorGuid)) continue;
            StoreService.TryGetHairDyeName(slug, out var friendlyName);
            result.Add(new UnlockedAvatarItemDto
            {
                AvatarItemType = AvatarItemType.HairDye,
                AvatarItemDesc = hairColorGuid,
                PlatformMask = unchecked((int)0xFFFFFFFF),
                FriendlyName = friendlyName,
                Tooltip = string.Empty,
                Rarity = 0,
            });
        }
        return Ok(result);
    }

    /// <summary>The set of GUIDs the bundled
    /// <c>AvatarItemWardrobeRuntimeConfig.avatarItemDataLookup</c>
    /// contains. Exposed so other controllers (StoreService seed,
    /// PlayerService starter inventory) can validate their seed
    /// data against the same safe list.</summary>
    public static IReadOnlySet<string> SafeGuids => _catalog.Value.SafeGuids;

    /// <summary>Master catalog of all renderable items, keyed by
    /// GUID. Used by callers that need item metadata (slot type,
    /// name, hair-color flags) outside of the per-player ownership
    /// check.</summary>
    public static IReadOnlyDictionary<string, UnlockedAvatarItemDto> Catalog
        => _catalog.Value.Items;

    /// <summary>GET <c>api/avatar/v1/lockeditems</c> — metadata for
    /// specific avatar item descriptions the caller does not own. The
    /// store UI calls this with item descs from purchasable rows and
    /// expects the same item-detail shape used by unlocked items,
    /// minus ownership. We resolve against the safe runtime catalog so
    /// unknown GUIDs never reach the client parser.</summary>
    [HttpGet("api/avatar/v1/lockeditems")]
    [AllowAnonymous]
    public async Task<IActionResult> LockedItems()
    {
        var requested = RequestedAvatarItemGuids().ToList();
        if (requested.Count == 0) return Ok(Array.Empty<object>());

        var owned = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        var pid = this.CurrentPlayerId();
        if (pid is long me)
        {
            var invJson = await db.Avatars
                .Where(a => a.PlayerId == me)
                .Select(a => a.InventoryJson)
                .FirstOrDefaultAsync();
            foreach (var guid in ParseInventory(invJson))
                owned.Add(guid);
        }

        var catalog = _catalog.Value.Items;
        var rows = requested
            .Where(guid => !owned.Contains(guid))
            .Distinct(StringComparer.OrdinalIgnoreCase)
            .Select(guid => catalog.TryGetValue(guid, out var item) ? item : null)
            .Where(item => item is not null)
            .Select(item => new
            {
                item!.AvatarItemType,
                item.AvatarItemDesc,
                item.FriendlyName,
                item.Tooltip,
                item.Rarity,
            })
            .ToArray();
        return Ok(rows);
    }

    /// <summary>Per-OutfitType slot index → list of GUIDs in that slot.
    /// Used by <see cref="DorkNet.Server.Services.PlayerService"/> to
    /// build a starter loadout (one per slot) and a starter inventory
    /// (a few per slot).</summary>
    public static IReadOnlyDictionary<int, List<string>> BySlot
        => _catalog.Value.BySlot;

    public static bool TryGetOutfitType(string guid, out int outfitType) =>
        _catalog.Value.SlotByGuid.TryGetValue(guid, out outfitType);

    private IEnumerable<string> RequestedAvatarItemGuids()
    {
        foreach (var pair in Request.Query)
        foreach (var raw in pair.Value)
        foreach (var part in (raw ?? string.Empty).Split(';', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries))
        {
            var value = part.Trim();
            if (string.IsNullOrWhiteSpace(value)) continue;
            var comma = value.IndexOf(',');
            if (comma >= 0) value = value[..comma];
            if (Guid.TryParse(value, out _)) yield return value;
        }
    }

    private static List<string> ParseInventory(string? json)
    {
        if (string.IsNullOrWhiteSpace(json)) return new();
        try
        {
            var strings = JsonSerializer.Deserialize<List<string>>(json);
            if (strings is not null) return strings;
        }
        catch { }

        try
        {
            using var doc = JsonDocument.Parse(json);
            if (doc.RootElement.ValueKind != JsonValueKind.Array) return new();

            var result = new List<string>();
            foreach (var element in doc.RootElement.EnumerateArray())
            {
                string? value = null;
                if (element.ValueKind == JsonValueKind.String)
                    value = element.GetString();
                else if (element.ValueKind == JsonValueKind.Object &&
                         element.TryGetProperty("itemId", out var itemId) &&
                         itemId.ValueKind == JsonValueKind.String)
                    value = itemId.GetString();

                if (string.IsNullOrWhiteSpace(value)) continue;
                const string wardrobePrefix = "wardrobe-";
                if (value.StartsWith(wardrobePrefix, StringComparison.Ordinal))
                    value = value[wardrobePrefix.Length..];
                var comma = value.IndexOf(',');
                if (comma >= 0)
                    value = value[..comma];
                result.Add(value);
            }

            return result
                .Distinct(StringComparer.OrdinalIgnoreCase)
                .ToList();
        }
        catch { return new(); }
    }

    private static HashSet<string> ParseEquippedItemGuids(string? outfitSelections)
    {
        var result = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        if (string.IsNullOrWhiteSpace(outfitSelections)) return result;

        foreach (var selection in outfitSelections.Split(';', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries))
        {
            var comma = selection.IndexOf(',');
            var guid = comma >= 0 ? selection[..comma] : selection;
            if (!string.IsNullOrWhiteSpace(guid))
                result.Add(guid.Trim());
        }

        return result;
    }

    private sealed record CatalogData(
        IReadOnlyDictionary<string, UnlockedAvatarItemDto> Items,
        IReadOnlySet<string> SafeGuids,
        IReadOnlyDictionary<int, List<string>> BySlot,
        IReadOnlyDictionary<string, int> SlotByGuid);

    private static CatalogData LoadCatalog()
    {
        // Try both lowercase 'data/' (csproj None+Link target) and
        // uppercase 'Data/' (git-tracked source folder) so case-sensitivity
        // mismatches between Windows (where the dev wrote the path) and
        // Linux (where Coolify builds the container) can't lose the lookup
        // file. Without this fallback, a single missed file → empty
        // SafeGuids → StoreService.SeedAsync skips its stale-row cleanup
        // → 418 swatch-GUID rows ship live → every store tile renders as
        // Hat_Angler.
        var candidates = new[]
        {
            Path.Combine(AppContext.BaseDirectory, "data", "avatar_item_lookup.json"),
            Path.Combine(AppContext.BaseDirectory, "Data", "avatar_item_lookup.json"),
            Path.Combine(Directory.GetCurrentDirectory(), "data", "avatar_item_lookup.json"),
            Path.Combine(Directory.GetCurrentDirectory(), "Data", "avatar_item_lookup.json"),
        };
        var path = candidates.FirstOrDefault(System.IO.File.Exists);
        Console.WriteLine(path is null
            ? $"[avatar-catalog] avatar_item_lookup.json not found in any of: {string.Join(", ", candidates)}"
            : $"[avatar-catalog] loading from {path}");
        if (path is null) return new CatalogData(
            new Dictionary<string, UnlockedAvatarItemDto>(),
            new HashSet<string>(),
            new Dictionary<int, List<string>>(),
            new Dictionary<string, int>());

        using var fs = System.IO.File.OpenRead(path);
        var dump = JsonSerializer.Deserialize<LookupFile>(fs,
            new JsonSerializerOptions { PropertyNameCaseInsensitive = true })
            ?? new LookupFile();

        var items = new Dictionary<string, UnlockedAvatarItemDto>(dump.Items.Count, StringComparer.OrdinalIgnoreCase);
        var safe = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        var bySlot = new Dictionary<int, List<string>>();
        var slotByGuid = new Dictionary<string, int>(StringComparer.OrdinalIgnoreCase);

        foreach (var row in dump.Items)
        {
            if (string.IsNullOrEmpty(row.Guid)) continue;
            safe.Add(row.Guid);
            // Prefer the baked display_name from the JSON if present
            // (tools/add-display-names.py writes it once per refresh).
            // Falls back to the raw-name cleanup if the field is missing
            // — e.g. partial dumps or older fixture files.
            var pretty = !string.IsNullOrEmpty(row.DisplayName)
                ? row.DisplayName
                : PrettyName(row.Name);
            items[row.Guid] = new UnlockedAvatarItemDto
            {
                // AvatarItemType is the wire enum the watch parses
                // (Outfit=0 / HairDye=1), not the slot. Rows in
                // avatarItemDataLookup are wearable avatar items, including
                // hair meshes that *use* hair color. They must still be sent
                // as Outfit; sending HairDye makes the client treat the item
                // GUID as a color GUID and log "Can not find hair dye color".
                AvatarItemType = AvatarItemType.Outfit,
                AvatarItemDesc = row.Guid + ",,,",
                PlatformMask = unchecked((int)0xFFFFFFFF),
                FriendlyName = pretty,
                Tooltip = string.Empty,
                Rarity = 0,
            };
            if (!bySlot.TryGetValue(row.OutfitType, out var lst))
                bySlot[row.OutfitType] = lst = new List<string>();
            lst.Add(row.Guid);
            slotByGuid[row.Guid] = row.OutfitType;
        }

        return new CatalogData(items, safe, bySlot, slotByGuid);
    }

    private static string PrettyName(string raw)
    {
        if (string.IsNullOrEmpty(raw)) return string.Empty;
        // Strip leading/trailing parens that the bundled config wraps
        // names in, then turn underscores into spaces. Keep it simple —
        // the watch shows whatever string we send.
        var trimmed = raw.Trim().TrimStart('(').TrimEnd(')');
        // Drop common asset-name suffixes. Items in the runtime config
        // use the raw asset name (e.g. "Hat_Wizard", "shirt_sherlock");
        // the watch never normalises these, so we do it server-side.
        var s = trimmed.Replace('_', ' ').Trim();
        return s;
    }

    /// <summary>Shape of <c>data/avatar_item_lookup.json</c> as written
    /// by <c>tools/AvatarCatalogDumpPatch</c>.</summary>
    private sealed class LookupFile
    {
        [JsonPropertyName("items")]
        public List<LookupItem> Items { get; set; } = new();

        // Auxiliary GUID lists (prefab/mask/swatch/decal). Not used
        // server-side yet — they'd matter for resolving asset
        // references the watch might subsequently request, but the
        // wire protocol only ever ships the AvatarItem GUID.
        [JsonPropertyName("prefab_guids")]
        public List<string> PrefabGuids { get; set; } = new();
        [JsonPropertyName("mask_guids")]
        public List<string> MaskGuids { get; set; } = new();
        [JsonPropertyName("swatch_guids")]
        public List<string> SwatchGuids { get; set; } = new();
        [JsonPropertyName("decal_guids")]
        public List<string> DecalGuids { get; set; } = new();
    }

    private sealed class LookupItem
    {
        [JsonPropertyName("guid")]         public string Guid { get; set; } = string.Empty;
        [JsonPropertyName("name")]         public string Name { get; set; } = string.Empty;
        // Algorithmically derived from `name` by
        // tools/add-display-names.py — Rec Room's official UI strings
        // live in Unity asset bundles we can't read from a code dump,
        // so this is a best-effort cleanup. Optional — server falls
        // back to PrettyName() if missing.
        [JsonPropertyName("display_name")] public string? DisplayName { get; set; }
        [JsonPropertyName("outfit_type")]  public int OutfitType { get; set; }
        [JsonPropertyName("outfit_set")]   public int OutfitSet { get; set; }
        [JsonPropertyName("drawer_index")] public int DrawerIndex { get; set; }
        [JsonPropertyName("hides_hair")]      public bool HidesHair { get; set; }
        [JsonPropertyName("hides_hand")]      public bool HidesHand { get; set; }
        // hides_left_ear / hides_right_ear were added to AvatarItemData
        // in the 2020.12.18 client build. Optional in the JSON so older
        // dumps still deserialize.
        [JsonPropertyName("hides_left_ear")]  public bool HidesLeftEar { get; set; }
        [JsonPropertyName("hides_right_ear")] public bool HidesRightEar { get; set; }
        [JsonPropertyName("uses_hair_color")] public bool UsesHairColor { get; set; }
        [JsonPropertyName("uses_team_color")] public bool UsesTeamColor { get; set; }
        [JsonPropertyName("is_team_item")]    public bool IsTeamItem { get; set; }
    }

    /// <summary>Mirrors <c>RecNet.Avatars+AvatarItemType</c>
    /// (Avatars.cs:186-190).</summary>
    private static class AvatarItemType
    {
        public const int Outfit  = 0;
        public const int HairDye = 1;
    }

    /// <summary>OutfitType slot enum mirrored from
    /// <c>RecRoom.Avatar.Data.Shared.OutfitType</c>. Used by other
    /// callers (PlayerService, StoreService) for slot-aware seeding.</summary>
    public static class Slot
    {
        public const int Hat       = 0;
        public const int BackHead  = 1;
        public const int Hair      = 2;
        public const int Eye       = 10;
        public const int Mouth     = 20;
        public const int Neck      = 100;
        public const int Shirt     = 101;
        public const int Belt      = 102;
        public const int Pocket    = 103;
        public const int TeamShirt = 104;
        public const int Wrist     = 200;
        public const int Glove     = 201;
        public const int Watch     = 202;
        public const int TeamWrist = 203;
    }
}

public class UnlockedAvatarItemDto
{
    [JsonPropertyName("AvatarItemType")]
    public int AvatarItemType { get; set; }

    [JsonPropertyName("AvatarItemDesc")]
    public string AvatarItemDesc { get; set; } = string.Empty;

    [JsonPropertyName("PlatformMask")]
    public int PlatformMask { get; set; }

    [JsonPropertyName("FriendlyName")]
    public string FriendlyName { get; set; } = string.Empty;

    [JsonPropertyName("Tooltip")]
    public string Tooltip { get; set; } = string.Empty;

    [JsonPropertyName("Rarity")]
    public int Rarity { get; set; }
}