using Microsoft.AspNetCore.Mvc;
using SqlSugar;
using WIDESEA_Core;
using WIDESEA_Model.Models;

namespace WIDESEA_WMSServer.Controllers.Dashboard
{
    /// <summary>
    /// 仪表盘
    /// </summary>
    [Route("api/Dashboard")]
    [ApiController]
    public class DashboardController : ControllerBase
    {
        private readonly ISqlSugarClient _db;

        public DashboardController(ISqlSugarClient db)
        {
            _db = db;
        }

        /// <summary>
        /// 总览数据
        /// </summary>
        [HttpGet("Overview")]
        public async Task<WebResponseContent> Overview()
        {
            try
            {
                var today = DateTime.Today;
                var firstDayOfMonth = new DateTime(today.Year, today.Month, 1);

                // 今日入库数
                var todayInbound = await _db.Queryable<Dt_Task_Hty>()
                    .Where(t => t.InsertTime >= today && t.TaskType >= 500 && t.TaskType < 600)
                    .CountAsync();

                // 今日出库数
                var todayOutbound = await _db.Queryable<Dt_Task_Hty>()
                    .Where(t => t.InsertTime >= today && t.TaskType >= 100 && t.TaskType < 200)
                    .CountAsync();

                // 本月入库数
                var monthInbound = await _db.Queryable<Dt_Task_Hty>()
                    .Where(t => t.InsertTime >= firstDayOfMonth && t.TaskType >= 500 && t.TaskType < 600)
                    .CountAsync();

                // 本月出库数
                var monthOutbound = await _db.Queryable<Dt_Task_Hty>()
                    .Where(t => t.InsertTime >= firstDayOfMonth && t.TaskType >= 100 && t.TaskType < 200)
                    .CountAsync();

                // 当前总库存
                var totalStock = await _db.Queryable<Dt_StockInfo>().CountAsync();

                return WebResponseContent.Instance.OK(null, new
                {
                    TodayInbound = todayInbound,
                    TodayOutbound = todayOutbound,
                    MonthInbound = monthInbound,
                    MonthOutbound = monthOutbound,
                    TotalStock = totalStock
                });
            }
            catch (Exception ex)
            {
                return WebResponseContent.Instance.Error($"总览数据获取失败: {ex.Message}");
            }
        }

        /// <summary>
        /// 每日统计
        /// </summary>
        /// <remarks>
        /// 注意：数据在 SQL 层过滤后，在应用层按日期分组。
        /// SqlSugar 的 GroupBy 不支持对 .Date 这样的计算列直接生成 SQL GROUP BY，
        /// 因此采用此方式以确保跨数据库兼容性。
        /// </remarks>
        [HttpGet("DailyStats")]
        public async Task<WebResponseContent> DailyStats([FromQuery] int days = 30)
        {
            try
            {
                if (days <= 0) days = 30;
                if (days > 365) days = 365;

                var startDate = DateTime.Today.AddDays(-days + 1);

                var query = await _db.Queryable<Dt_Task_Hty>()
                    .Where(t => t.InsertTime >= startDate)
                    .Select(t => new { t.InsertTime, t.TaskType })
                    .ToListAsync();

                var result = query
                    .GroupBy(t => t.InsertTime.Date)
                    .Select(g => new
                    {
                        Date = g.Key.ToString("yyyy-MM-dd"),
                        Inbound = g.Count(t => t.TaskType >= 500 && t.TaskType < 600),
                        Outbound = g.Count(t => t.TaskType >= 100 && t.TaskType < 200)
                    })
                    .OrderBy(x => x.Date)
                    .ToList();

                return WebResponseContent.Instance.OK(null, result);
            }
            catch (Exception ex)
            {
                return WebResponseContent.Instance.Error($"每日统计获取失败: {ex.Message}");
            }
        }

        /// <summary>
        /// 每周统计
        /// </summary>
        /// <remarks>
        /// 注意：数据在 SQL 层过滤后，在应用层按 ISO 8601 周键分组。
        /// 周键为 "YYYY-Www" 格式，无法直接在 SQL 层用 GROUP BY 实现。
        /// </remarks>
        [HttpGet("WeeklyStats")]
        public async Task<WebResponseContent> WeeklyStats([FromQuery] int weeks = 12)
        {
            try
            {
                if (weeks <= 0) weeks = 12;

                var startDate = DateTime.Today.AddDays(-weeks * 7);

                var query = await _db.Queryable<Dt_Task_Hty>()
                    .Where(t => t.InsertTime >= startDate)
                    .Select(t => new { t.InsertTime, t.TaskType })
                    .ToListAsync();

                var result = query
                    .GroupBy(t => GetWeekKey(t.InsertTime))
                    .Select(g => new
                    {
                        Week = g.Key,
                        Inbound = g.Count(t => t.TaskType >= 500 && t.TaskType < 600),
                        Outbound = g.Count(t => t.TaskType >= 100 && t.TaskType < 200)
                    })
                    .OrderBy(x => x.Week)
                    .ToList();

                return WebResponseContent.Instance.OK(null, result);
            }
            catch (Exception ex)
            {
                return WebResponseContent.Instance.Error($"每周统计获取失败: {ex.Message}");
            }
        }

        private string GetWeekKey(DateTime date)
        {
            // 获取周一开始的周 (ISO 8601)
            var diff = (7 + (date.DayOfWeek - DayOfWeek.Monday)) % 7;
            var monday = date.AddDays(-diff);
            var weekNum = System.Globalization.CultureInfo.InvariantCulture
                .Calendar.GetWeekOfYear(monday, System.Globalization.CalendarWeekRule.FirstFourDayWeek, DayOfWeek.Monday);
            return $"{monday.Year}-W{weekNum:D2}";
        }

        /// <summary>
        /// 每月统计
        /// </summary>
        /// <remarks>
        /// 注意：数据在 SQL 层过滤后，在应用层按年月分组。
        /// SqlSugar 的 GroupBy 不支持匿名对象 (Year, Month) 直接映射到 SQL GROUP BY，
        /// 因此采用此方式以确保跨数据库兼容性。
        /// </remarks>
        [HttpGet("MonthlyStats")]
        public async Task<WebResponseContent> MonthlyStats([FromQuery] int months = 12)
        {
            try
            {
                if (months <= 0) months = 12;

                var startDate = DateTime.Today.AddMonths(-months + 1);
                startDate = new DateTime(startDate.Year, startDate.Month, 1);

                var query = await _db.Queryable<Dt_Task_Hty>()
                    .Where(t => t.InsertTime >= startDate)
                    .Select(t => new { t.InsertTime, t.TaskType })
                    .ToListAsync();

                var result = query
                    .GroupBy(t => new { t.InsertTime.Year, t.InsertTime.Month })
                    .Select(g => new
                    {
                        Month = $"{g.Key.Year}-{g.Key.Month:D2}",
                        Inbound = g.Count(t => t.TaskType >= 500 && t.TaskType < 600),
                        Outbound = g.Count(t => t.TaskType >= 100 && t.TaskType < 200)
                    })
                    .OrderBy(x => x.Month)
                    .ToList();

                return WebResponseContent.Instance.OK(null, result);
            }
            catch (Exception ex)
            {
                return WebResponseContent.Instance.Error($"每月统计获取失败: {ex.Message}");
            }
        }

        /// <summary>
        /// 库存库龄分布
        /// </summary>
        [HttpGet("StockAgeDistribution")]
        public async Task<WebResponseContent> StockAgeDistribution()
        {
            try
            {
                var today = DateTime.Today;

                // 使用 SQL 直接分组统计，避免加载所有数据到内存
                var result = new[]
                {
                    new { Range = "7天内", Count = await _db.Queryable<Dt_StockInfo>().Where(s => SqlFunc.DateDiff(DateType.Day, s.CreateDate, today) <= 7).CountAsync() },
                    new { Range = "7-30天", Count = await _db.Queryable<Dt_StockInfo>().Where(s => SqlFunc.DateDiff(DateType.Day, s.CreateDate, today) > 7 && SqlFunc.DateDiff(DateType.Day, s.CreateDate, today) <= 30).CountAsync() },
                    new { Range = "30-90天", Count = await _db.Queryable<Dt_StockInfo>().Where(s => SqlFunc.DateDiff(DateType.Day, s.CreateDate, today) > 30 && SqlFunc.DateDiff(DateType.Day, s.CreateDate, today) <= 90).CountAsync() },
                    new { Range = "90天以上", Count = await _db.Queryable<Dt_StockInfo>().Where(s => SqlFunc.DateDiff(DateType.Day, s.CreateDate, today) > 90).CountAsync() }
                };

                return WebResponseContent.Instance.OK(null, result);
            }
            catch (Exception ex)
            {
                return WebResponseContent.Instance.Error($"库存库龄分布获取失败: {ex.Message}");
            }
        }

        /// <summary>
        /// 各仓库库存分布
        /// </summary>
        /// <remarks>
        /// 使用 SQL GROUP BY 在数据库层面聚合，避免加载全部库存记录到内存。
        /// </remarks>
        [HttpGet("StockByWarehouse")]
        public async Task<WebResponseContent> StockByWarehouse()
        {
            try
            {
                // 查询仓库名称
                var warehouses = await _db.Queryable<Dt_Warehouse>()
                    .Select(w => new { w.WarehouseId, w.WarehouseName })
                    .ToListAsync();
                var warehouseDict = warehouses.ToDictionary(w => w.WarehouseId, w => w.WarehouseName);

                // 使用 SQL GROUP BY 在数据库层面聚合，仅返回聚合结果
                var stockGroups = await _db.Queryable<Dt_StockInfo>()
                    .GroupBy(s => s.WarehouseId)
                    .Select(s => new { s.WarehouseId, Count = SqlFunc.AggregateCount(s.Id) })
                    .ToListAsync();

                var result = stockGroups
                    .Select(g => new
                    {
                        Warehouse = warehouseDict.TryGetValue(g.WarehouseId, out var name) ? name : $"仓库{g.WarehouseId}",
                        Count = g.Count
                    })
                    .ToList();

                return WebResponseContent.Instance.OK(null, result);
            }
            catch (Exception ex)
            {
                return WebResponseContent.Instance.Error($"各仓库库存分布获取失败: {ex.Message}");
            }
        }
    }
}