using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;
using SVSim.Database;
using SVSim.Database.Enums;
using SVSim.Database.Models;
using SVSim.Database.Repositories.Viewer;
using SVSim.EmulatedEntrypoint.Extensions;
using SVSim.EmulatedEntrypoint.Infrastructure;
using SVSim.EmulatedEntrypoint.Models.Dtos.Requests.Admin;
using SVSim.EmulatedEntrypoint.Models.Dtos.Responses.Admin;

namespace SVSim.EmulatedEntrypoint.Controllers;

/// <summary>
/// Util endpoints for bootstrapping the dev environment. Anonymous-allowed today — security
/// audit pending (don't expose these to the public internet).
/// </summary>
public class AdminController : SVSimController
{
    private readonly IViewerRepository _viewerRepository;
    private readonly SVSimDbContext _dbContext;
    private readonly ILogger<AdminController> _logger;

    public AdminController(IViewerRepository viewerRepository, SVSimDbContext dbContext,
        ILogger<AdminController> logger)
    {
        _viewerRepository = viewerRepository;
        _dbContext = dbContext;
        _logger = logger;
    }

    /// <summary>
    /// Upsert a viewer from external data (typically captured from the live game via the
    /// SVSimLoader dump). Matches existing viewers by SteamId; creates a new one if missing.
    /// Only essential fields are imported today — extend as needed.
    /// </summary>
    [AllowAnonymous]
    [HttpPost("import_viewer")]
    public async Task<ActionResult<ImportViewerResponse>> ImportViewer(ImportViewerRequest request)
    {
        if (request.SteamId == 0)
        {
            return BadRequest("steam_id is required");
        }

        // SocialAccountConnection is [Owned]-by-Viewer — can't query the owned table directly;
        // look up the Viewer with a matching owned connection instead.
        var existing = await _dbContext.Viewers
            .AsNoTracking()
            .FirstOrDefaultAsync(v => v.SocialAccountConnections.Any(sac =>
                sac.AccountType == SocialAccountType.Steam && sac.AccountId == request.SteamId));

        long viewerId;
        bool wasCreated;

        if (existing is null)
        {
            var created = await _viewerRepository.RegisterViewer(
                request.DisplayName ?? "Imported Viewer",
                SocialAccountType.Steam,
                request.SteamId);
            viewerId = created.Id;
            wasCreated = true;
        }
        else
        {
            viewerId = existing.Id;
            wasCreated = false;
        }

        // Reload with all the nav properties we need to mutate. RegisterViewer SaveChanges'd
        // already, so we re-fetch with full graph and apply the updates. AsSplitQuery to avoid
        // the cartesian-explosion across all the many-to-many cosmetic collections.
        var viewer = await _dbContext.Viewers
            .AsSplitQuery()
            .Include(v => v.Info).ThenInclude(i => i.SelectedEmblem)
            .Include(v => v.Info).ThenInclude(i => i.SelectedDegree)
            .Include(v => v.Currency)
            .Include(v => v.MissionData)
            .Include(v => v.Classes).ThenInclude(c => c.Class)
            .Include(v => v.Sleeves)
            .Include(v => v.Emblems)
            .Include(v => v.Degrees)
            .Include(v => v.LeaderSkins)
            .Include(v => v.MyPageBackgrounds)
            .Include(v => v.Cards).ThenInclude(c => c.Card)
            .Include(v => v.Items).ThenInclude(i => i.Item)
            .Include(v => v.Decks).ThenInclude(d => d.Cards)
            .FirstAsync(v => v.Id == viewerId);

        if (request.DisplayName is not null) viewer.DisplayName = request.DisplayName;
        if (request.CountryCode is not null) viewer.Info.CountryCode = request.CountryCode;
        if (request.TutorialState.HasValue) viewer.MissionData.TutorialState = request.TutorialState.Value;

        if (request.Currency is not null)
        {
            if (request.Currency.Crystals.HasValue) viewer.Currency.Crystals = request.Currency.Crystals.Value;
            if (request.Currency.Rupees.HasValue) viewer.Currency.Rupees = request.Currency.Rupees.Value;
            if (request.Currency.RedEther.HasValue) viewer.Currency.RedEther = request.Currency.RedEther.Value;
        }

        if (request.SelectedEmblemId.HasValue)
        {
            var emblem = await _dbContext.Emblems.FindAsync(request.SelectedEmblemId.Value);
            if (emblem is not null) viewer.Info.SelectedEmblem = emblem;
        }
        if (request.SelectedDegreeId.HasValue)
        {
            var degree = await _dbContext.Degrees.FindAsync(request.SelectedDegreeId.Value);
            if (degree is not null) viewer.Info.SelectedDegree = degree;
        }

        await ReplaceOwned(viewer.Sleeves, request.OwnedSleeveIds, _dbContext.Sleeves);
        await ReplaceOwned(viewer.Emblems, request.OwnedEmblemIds, _dbContext.Emblems);
        await ReplaceOwned(viewer.Degrees, request.OwnedDegreeIds, _dbContext.Degrees);
        await ReplaceOwned(viewer.LeaderSkins, request.OwnedLeaderSkinIds, _dbContext.LeaderSkins);
        await ReplaceOwned(viewer.MyPageBackgrounds, request.OwnedMyPageBackgroundIds, _dbContext.MyPageBackgrounds);

        if (request.Classes is not null)
        {
            foreach (var importClass in request.Classes)
            {
                var existingClass = viewer.Classes.FirstOrDefault(c => c.Class.Id == importClass.ClassId);
                if (existingClass is not null)
                {
                    existingClass.Level = importClass.Level;
                    existingClass.Exp = importClass.Exp;
                }
            }
        }

        // Accumulates distinct card_ids referenced by the import (owned list + deck lists)
        // that aren't in our card master. Surfaced in the response and logged after save.
        var skippedCardIds = new HashSet<long>();

        if (request.OwnedCards is not null)
        {
            var wanted = request.OwnedCards
                .GroupBy(c => c.CardId)
                .Select(g => g.First())
                .ToList();
            var ids = wanted.Select(c => c.CardId).ToList();
            var cardMaster = await _dbContext.Cards
                .Where(c => ids.Contains(c.Id))
                .ToDictionaryAsync(c => c.Id);

            viewer.Cards.Clear();
            foreach (var c in wanted)
            {
                if (!cardMaster.TryGetValue(c.CardId, out var card))
                {
                    skippedCardIds.Add(c.CardId);
                    continue;
                }
                viewer.Cards.Add(new OwnedCardEntry
                {
                    Card = card,
                    Count = Math.Clamp(c.Count, 1, OwnedCardEntry.MaxCopies),
                    IsProtected = c.IsProtected,
                });
            }
        }

        if (request.Items is not null)
        {
            var wanted = request.Items
                .GroupBy(i => i.ItemId)
                .Select(g => g.First())
                .ToList();
            var ids = wanted.Select(i => i.ItemId).ToList();
            var itemMaster = await _dbContext.Items
                .Where(i => ids.Contains(i.Id))
                .ToDictionaryAsync(i => i.Id);

            viewer.Items.Clear();
            foreach (var i in wanted)
            {
                if (!itemMaster.TryGetValue(i.ItemId, out var item)) continue; // unknown master id
                viewer.Items.Add(new OwnedItemEntry { Item = item, Count = i.Count, Viewer = viewer });
            }
        }

        if (request.Decks is not null)
        {
            var allDeckCardIds = request.Decks
                .Where(d => d.CardIdArray is not null)
                .SelectMany(d => d.CardIdArray!)
                .Distinct()
                .ToList();
            var deckCardMaster = await _dbContext.Cards
                .Where(c => allDeckCardIds.Contains(c.Id))
                .ToDictionaryAsync(c => c.Id);
            var classes = await _dbContext.Classes.Include(c => c.LeaderSkins).ToDictionaryAsync(c => c.Id);
            var sleeves = await _dbContext.Sleeves.ToDictionaryAsync(s => (long)s.Id);
            var leaderSkins = await _dbContext.LeaderSkins.ToDictionaryAsync(s => s.Id);
            var defaultSleeve = await _dbContext.Sleeves.FindAsync((int)DefaultSleeveId);
            var latestMyRotationId = (await _dbContext.MyRotationSettings.AsNoTracking()
                .Select(s => (int?)s.Id)
                .OrderByDescending(id => id)
                .FirstOrDefaultAsync())?.ToString();

            _dbContext.RemoveRange(viewer.Decks);
            viewer.Decks.Clear();

            foreach (var d in request.Decks)
            {
                // A /load/index dump carries every deck slot, most of them empty placeholders
                // (no cards). Skip them: the client manages empty slots itself (it's why the old
                // default-deck cloning was removed), and importing empty MyRotation slots would
                // otherwise persist decks with a bogus rotation id.
                if ((d.CardIdArray?.Count ?? 0) == 0) continue;

                Format format;
                try { format = FormatExtensions.FromApi(d.DeckFormat); }
                catch (ArgumentOutOfRangeException) { continue; } // skip unsupported wire format
                if (!classes.TryGetValue(d.ClassId, out var classEntry)) continue;

                SleeveEntry? sleeve = null;
                if (d.SleeveId.HasValue) sleeves.TryGetValue(d.SleeveId.Value, out sleeve);
                sleeve ??= defaultSleeve;

                LeaderSkinEntry? leaderSkin = null;
                if (d.LeaderSkinId.HasValue) leaderSkins.TryGetValue(d.LeaderSkinId.Value, out leaderSkin);
                leaderSkin ??= classEntry.DefaultLeaderSkin ?? classEntry.LeaderSkins.FirstOrDefault();

                if (sleeve is null || leaderSkin is null) continue;

                var cards = (d.CardIdArray ?? new List<long>())
                    .GroupBy(id => id)
                    .Where(g =>
                    {
                        if (deckCardMaster.ContainsKey(g.Key)) return true;
                        skippedCardIds.Add(g.Key);
                        return false;
                    })
                    .Select(g => new DeckCard { Card = deckCardMaster[g.Key], Count = g.Count() })
                    .ToList();

                viewer.Decks.Add(new ShadowverseDeckEntry
                {
                    Name = d.DeckName ?? $"Deck {d.DeckNo}",
                    Number = d.DeckNo,
                    Format = format,
                    Class = classEntry,
                    Sleeve = sleeve,
                    LeaderSkin = leaderSkin,
                    RandomLeaderSkin = (d.IsRandomLeaderSkin ?? 0) != 0,
                    Cards = cards,
                    MyRotationId = format == Format.MyRotation ? (d.MyRotationId ?? latestMyRotationId) : null,
                });
            }
        }

        await _dbContext.SaveChangesAsync();

        if (skippedCardIds.Count > 0)
        {
            _logger.LogWarning(
                "ImportViewer (steam_id={SteamId}, viewer_id={ViewerId}): skipped {Count} unknown " +
                "card_id(s) not present in the card master. Sample: [{Sample}]",
                request.SteamId, viewer.Id, skippedCardIds.Count,
                string.Join(", ", skippedCardIds.Take(20)));
        }

        return new ImportViewerResponse
        {
            ViewerId = viewer.Id,
            ShortUdid = viewer.ShortUdid,
            WasCreated = wasCreated,
            SkippedCardCount = skippedCardIds.Count,
        };
    }

    /// <summary>
    /// Replaces the owned-collection with the master rows matching the supplied ids.
    /// Null `ids` is a no-op (preserve existing). Empty list clears the collection.
    /// </summary>
    private async Task ReplaceOwned<TEntity>(List<TEntity> owned, List<int>? ids, DbSet<TEntity> table)
        where TEntity : class
    {
        if (ids is null) return;
        owned.Clear();
        if (ids.Count == 0) return;

        var rows = await table.Where(e => ids.Contains(EF.Property<int>(e, "Id"))).ToListAsync();
        owned.AddRange(rows);
    }

    /// <summary>
    /// Fallback sleeve id used when an imported deck has no resolvable <c>sleeve_id</c>.
    /// 3000011 is prod's default deck sleeve.
    /// </summary>
    private const long DefaultSleeveId = 3000011L;
}