using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Http;

/// <summary>
/// AncestralTabletStatisticsController 的摘要描述
/// </summary>
public class AncestralTabletStatisticsController:ApiController
{
    private Model.ezEntities db = new Model.ezEntities();
    [HttpGet]
    [Route("api/ancestraltablet/statistics/positions/availablepositions")]
    public IHttpActionResult GetAvailablePositions()
    {
        var query =
            from a in db.AncestralTabletArea // 区域表
            join p in db.AncestralTabletPosition
                on a.AreaId equals p.AreaId into ap
            from p in ap.DefaultIfEmpty()
            join r in db.AncestralTabletRegistrant
                on p.PositionId equals r.PositionId into pr
            from r in pr.DefaultIfEmpty()
            group new { a, p, r } by new { a.AreaId, a.AreaName } into g
            select new
            {
                AreaId = g.Key.AreaId,
                AreaName = g.Key.AreaName,
                TotalPositions = g.Count(x => x.p != null),                   // 总位置数
                AvailableCount = g.Count(x => x.p != null && x.r == null)     // 可用位置数（未登记）
            };

        var result = query.ToList();
        return Ok(result);
    }

}