using System.Linq.Expressions;
using Fake.Application;
using Microsoft.AspNetCore.Mvc;
using Oms.Application.Dtos.PlatformStore;
using Oms.Application.Dtos.Shared;
using Oms.Application.Shared;
using Oms.Domain.CustomersAggregate.Repositories;
using Oms.Domain.OrdersAggregate.Entities;
using Oms.Domain.OrdersAggregate.Repositories;
using Oms.Domain.WarehouseAggregate.Consts;

namespace Oms.Application.Services.Orders;

/// <summary>
/// 店铺授权 API 服务。
/// </summary>
[ApiExplorerSettings(GroupName = "OMS-Order")]
public class PlatformStoreService : ApplicationService
{
    private ICustomerRepository CustomerRepository => LazyServiceProvider.GetRequiredService<ICustomerRepository>();
    private ISalesStoreRepository StoreRepository => LazyServiceProvider.GetRequiredService<ISalesStoreRepository>();

    /// <summary>
    /// 查询店铺授权列表。
    /// </summary>
    /// <param name="input">入参：店铺分页查询条件。</param>
    /// <returns>店铺分页结果。</returns>
    [HttpPost("/order/platform-store/list")]
    public async Task<OmsPageResult<PlatformStoreOutput>> GetListAsync(PlatformStorePageInput input)
    {
        var customerId = await WarehouseCustomerHelper.ResolveListCustomerIdAsync(
            CustomerRepository,
            CurrentUser,
            input.CustomerId);
        var predicate = BuildListPredicate(customerId, input);
        var pageIndex = OmsDocHelper.NormalizePage(input.Page);
        var pageSize = OmsDocHelper.NormalizePageSize(input.PageSize);
        var entities = await StoreRepository.GetPagedListAsync(
            predicate,
            pageIndex,
            pageSize,
            new Dictionary<string, bool> { [nameof(SalesStore.UpdateTime)] = false, [nameof(SalesStore.Id)] = false });
        var total = await StoreRepository.CountAsync(predicate);

        return new OmsPageResult<PlatformStoreOutput>
        {
            Items = entities.Select(MapOutput).ToList(),
            Total = total
        };
    }

    /// <summary>
    /// 获取店铺 OAuth 授权地址。
    /// </summary>
    /// <param name="input">入参：平台编码与回调地址。</param>
    /// <returns>授权跳转 URL。</returns>
    [HttpPost("/order/platform-store/auth-url")]
    public async Task<PlatformStoreAuthUrlOutput> GetAuthUrlAsync(PlatformStoreAuthUrlInput input)
    {
        await WarehouseCustomerHelper.ResolveRequiredCustomerIdAsync(
            CustomerRepository,
            CurrentUser,
            input.CustomerId);

        var platform = input.PlatformCode.Trim().ToLowerInvariant();
        var redirect = string.IsNullOrWhiteSpace(input.RedirectUri)
            ? "https://localhost/oauth/callback"
            : input.RedirectUri.Trim();

        return new PlatformStoreAuthUrlOutput
        {
            AuthUrl = $"https://oauth.example.com/{platform}?redirect={Uri.EscapeDataString(redirect)}",
            Message = "OAuth 对接待平台 SDK 接入，当前返回占位地址"
        };
    }

    /// <summary>
    /// 保存店铺授权（新增或编辑）。
    /// </summary>
    /// <param name="input">入参：店铺保存数据。</param>
    /// <returns>保存后的店铺信息。</returns>
    [HttpPost("/order/platform-store/save")]
    public async Task<PlatformStoreOutput> SaveAsync(PlatformStoreSaveInput input)
    {
        var customerId = await WarehouseCustomerHelper.ResolveRequiredCustomerIdAsync(
            CustomerRepository,
            CurrentUser,
            input.CustomerId);
        var nickname = input.StoreNickname.Trim();
        if (string.IsNullOrWhiteSpace(nickname))
        {
            throw new BusinessException("店铺昵称不能为空");
        }

        SalesStore entity;
        if (input.Id > 0)
        {
            entity = await GetStoreOrThrowAsync(customerId, input.Id);
        }
        else
        {
            entity = new SalesStore
            {
                CustomerId = customerId,
                PlatformCode = string.IsNullOrWhiteSpace(input.PlatformCode) ? "manual" : input.PlatformCode.Trim(),
                AuthStatus = SalesStoreAuthStatusCodes.Active,
                AuthTime = DateTime.Now
            };
        }

        entity.StoreNickname = nickname;
        entity.PlatformAccount = string.IsNullOrWhiteSpace(input.PlatformAccount) ? null : input.PlatformAccount.Trim();
        entity.SiteCountry = string.IsNullOrWhiteSpace(input.SiteCountry) ? null : input.SiteCountry.Trim();
        entity.IsAutoFulfill = input.IsAutoFulfill;
        entity.Remark = string.IsNullOrWhiteSpace(input.Remark) ? null : input.Remark.Trim();

        if (input.Id > 0)
        {
            await StoreRepository.UpdateAsync(entity);
        }
        else
        {
            await StoreRepository.InsertAsync(entity);
        }

        return MapOutput(entity);
    }

    /// <summary>
    /// 删除店铺授权。
    /// </summary>
    /// <param name="input">入参：店铺 ID 列表。</param>
    [HttpPost("/order/platform-store/delete")]
    public async Task DeleteAsync(PlatformStoreIdsInput input)
    {
        if (input.Ids.Count == 0)
        {
            throw new BusinessException("请选择要删除的店铺");
        }

        var customerId = await WarehouseCustomerHelper.ResolveListCustomerIdAsync(
            CustomerRepository,
            CurrentUser,
            null);
        var (hasCustomerFilter, customerIdValue) = WarehouseCustomerHelper.ToCustomerFilter(customerId);
        var entities = await StoreRepository.GetListAsync(x =>
            (!hasCustomerFilter || x.CustomerId == customerIdValue) && input.Ids.Contains(x.Id));
        foreach (var entity in entities)
        {
            await StoreRepository.DeleteAsync(entity);
        }
    }

    private async Task<SalesStore> GetStoreOrThrowAsync(int? customerId, int id)
    {
        var entity = customerId.HasValue
            ? await StoreRepository.FirstOrDefaultAsync(x => x.Id == id && x.CustomerId == customerId.Value)
            : await StoreRepository.FirstOrDefaultAsync(x => x.Id == id);
        if (entity == null)
        {
            throw new BusinessException("店铺不存在");
        }

        return entity;
    }

    private static Expression<Func<SalesStore, bool>> BuildListPredicate(int? customerId, PlatformStorePageInput input)
    {
        var (hasCustomerFilter, customerIdValue) = WarehouseCustomerHelper.ToCustomerFilter(customerId);
        var platformCode = input.PlatformCode?.Trim();
        var nickname = input.StoreNickname?.Trim();
        var filter = input.ExpirationFilter?.Trim().ToLowerInvariant();
        var hasPlatformCode = !string.IsNullOrWhiteSpace(platformCode);
        var hasNickname = !string.IsNullOrWhiteSpace(nickname);
        var now = DateTime.Now;
        var within7Days = now.AddDays(7);

        // 显式按过期筛选分支构造表达式，避免嵌套三元被 ORM 翻译成非法 IIF。
        return filter switch
        {
            "expired" => x =>
                (!hasCustomerFilter || x.CustomerId == customerIdValue)
                && (!hasPlatformCode || x.PlatformCode == platformCode)
                && (!hasNickname || x.StoreNickname.Contains(nickname!))
                && x.TokenExpireTime.HasValue
                && x.TokenExpireTime < now,
            "within7days" => x =>
                (!hasCustomerFilter || x.CustomerId == customerIdValue)
                && (!hasPlatformCode || x.PlatformCode == platformCode)
                && (!hasNickname || x.StoreNickname.Contains(nickname!))
                && x.TokenExpireTime.HasValue
                && x.TokenExpireTime >= now
                && x.TokenExpireTime <= within7Days,
            "normal" => x =>
                (!hasCustomerFilter || x.CustomerId == customerIdValue)
                && (!hasPlatformCode || x.PlatformCode == platformCode)
                && (!hasNickname || x.StoreNickname.Contains(nickname!))
                && (!x.TokenExpireTime.HasValue || x.TokenExpireTime > within7Days),
            _ => x =>
                (!hasCustomerFilter || x.CustomerId == customerIdValue)
                && (!hasPlatformCode || x.PlatformCode == platformCode)
                && (!hasNickname || x.StoreNickname.Contains(nickname!))
        };
    }

    private static PlatformStoreOutput MapOutput(SalesStore entity) =>
        new()
        {
            Id = entity.Id,
            CustomerId = entity.CustomerId,
            PlatformCode = entity.PlatformCode,
            PlatformName = ResolvePlatformName(entity.PlatformCode),
            StoreNickname = entity.StoreNickname,
            PlatformAccount = entity.PlatformAccount,
            SiteCountry = entity.SiteCountry,
            AuthStatus = entity.AuthStatus,
            AuthTime = entity.AuthTime,
            TokenExpireTime = entity.TokenExpireTime,
            IsAutoFulfill = entity.IsAutoFulfill,
            Remark = entity.Remark,
            CreateTime = entity.CreateTime
        };

    private static string ResolvePlatformName(string platformCode) => platformCode.ToLowerInvariant() switch
    {
        "lazada" => "Lazada",
        "shopee" => "Shopee",
        "tiktok" => "TikTok",
        "temu" => "Temu",
        "manual" => "手工店铺",
        _ => platformCode
    };
}