using Bunny.Dao.Common.Result;
using Microsoft.EntityFrameworkCore;

namespace Bunny.Common.Context.Database;

public static class GetPagedResultAsync
{
    public static async Task<PageResult<T>> GetPagedListAsync<T>(IQueryable<T> source, int page, int limit)
    {
        var total = await source.CountAsync();
        IEnumerable<T> items = await source.Skip((page - 1) * limit).Take(limit).ToListAsync();
        return new PageResult<T>(page, limit, total, items);
    }

    public static async Task<PageResult<T>> GetPagedListFromSqlAsync<T>(DbContext dbContext, string sql, string table, int page, int limit)
        where T : class
    {
        // 计算SQL查询的总数
        var total = await dbContext.Set<T>().CountAsync();

        // 执行分页查询
        var paginatedSql =
            $"{sql} ORDER BY (SELECT NULL)  OFFSET {(page - 1) * limit} ROWS FETCH NEXT {limit} ROWS ONLY";
        IEnumerable<T> items = await dbContext.Set<T>().FromSqlRaw(paginatedSql).ToListAsync();

        return new PageResult<T>(page, limit, total, items);
    }
}