using System.Security.Claims;
using FictionArchive.Service.UserNovelDataService.Models.Database;
using FictionArchive.Service.UserNovelDataService.Models.DTOs;
using FictionArchive.Service.UserNovelDataService.Services;
using HotChocolate.Authorization;
using HotChocolate.Types;
using Microsoft.EntityFrameworkCore;

namespace FictionArchive.Service.UserNovelDataService.GraphQL;

public class Mutation
{
    [Authorize]
    [Error<InvalidOperationException>]
    public async Task<BookmarkPayload> UpsertBookmark(
        UserNovelDataServiceDbContext dbContext,
        ClaimsPrincipal claimsPrincipal,
        UpsertBookmarkInput input)
    {
        var oAuthProviderId = claimsPrincipal.FindFirst(ClaimTypes.NameIdentifier)?.Value;
        if (string.IsNullOrEmpty(oAuthProviderId))
        {
            throw new InvalidOperationException("Unable to determine current user identity");
        }

        var user = await dbContext.Users
            .FirstOrDefaultAsync(u => u.OAuthProviderId == oAuthProviderId);

        if (user == null)
        {
            // Auto-create user if not exists
            user = new User { OAuthProviderId = oAuthProviderId };
            dbContext.Users.Add(user);
            await dbContext.SaveChangesAsync();
        }

        var existingBookmark = await dbContext.Bookmarks
            .FirstOrDefaultAsync(b => b.UserId == user.Id && b.ChapterId == input.ChapterId);

        if (existingBookmark != null)
        {
            // Update existing
            existingBookmark.Description = input.Description;
        }
        else
        {
            // Create new
            existingBookmark = new Bookmark
            {
                UserId = user.Id,
                NovelId = input.NovelId,
                ChapterId = input.ChapterId,
                Description = input.Description
            };
            dbContext.Bookmarks.Add(existingBookmark);
        }

        await dbContext.SaveChangesAsync();

        return new BookmarkPayload
        {
            Success = true,
            Bookmark = new BookmarkDto
            {
                Id = existingBookmark.Id,
                ChapterId = existingBookmark.ChapterId,
                NovelId = existingBookmark.NovelId,
                Description = existingBookmark.Description,
                CreatedTime = existingBookmark.CreatedTime
            }
        };
    }

    [Authorize]
    [Error<InvalidOperationException>]
    public async Task<BookmarkPayload> RemoveBookmark(
        UserNovelDataServiceDbContext dbContext,
        ClaimsPrincipal claimsPrincipal,
        uint chapterId)
    {
        var oAuthProviderId = claimsPrincipal.FindFirst(ClaimTypes.NameIdentifier)?.Value;
        if (string.IsNullOrEmpty(oAuthProviderId))
        {
            throw new InvalidOperationException("Unable to determine current user identity");
        }

        var user = await dbContext.Users
            .AsNoTracking()
            .FirstOrDefaultAsync(u => u.OAuthProviderId == oAuthProviderId);

        if (user == null)
        {
            return new BookmarkPayload { Success = false };
        }

        var bookmark = await dbContext.Bookmarks
            .FirstOrDefaultAsync(b => b.UserId == user.Id && b.ChapterId == chapterId);

        if (bookmark == null)
        {
            return new BookmarkPayload { Success = false };
        }

        dbContext.Bookmarks.Remove(bookmark);
        await dbContext.SaveChangesAsync();

        return new BookmarkPayload { Success = true };
    }
}