using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Haoliang.Models.System;
using Haoliang.Data.Repositories;

namespace Haoliang.Data.Repositories
{
    public interface IAlarmRepository : IRepository<Alarm>
    {
        Task<IEnumerable<Alarm>> GetByDeviceIdAsync(int deviceId);
        Task<IEnumerable<Alarm>> GetByAlarmTypeAsync(AlarmType type);
        Task<IEnumerable<Alarm>> GetByStatusAsync(AlarmStatus status);
        Task<IEnumerable<Alarm>> GetByDateRangeAsync(DateTime startDate, DateTime endDate);
        Task<AlarmStatistics> GetAlarmStatisticsAsync(DateTime date);
        Task<IEnumerable<Alarm>> GetBySeverityAsync(AlarmSeverity severity);
        Task<IEnumerable<Alarm>> GetByDeviceAndDateRangeAsync(int deviceId, DateTime startDate, DateTime endDate);
        Task<int> CountActiveAlarmsAsync();
        Task<IEnumerable<Alarm>> GetActiveAlarmsAsync();
        Task<IEnumerable<Alarm>> GetAlarmsByPriorityAsync(AlarmPriority priority);
    }

    public class AlarmRepository : Repository<Alarm>, IAlarmRepository
    {
        private readonly CNCDbContext _context;

        public AlarmRepository(CNCDbContext context) : base(context)
        {
            _context = context;
        }

        public async Task<IEnumerable<Alarm>> GetByDeviceIdAsync(int deviceId)
        {
            return await _context.Alarms
                .Where(a => a.DeviceId == deviceId)
                .OrderByDescending(a => a.CreatedAt)
                .ToListAsync();
        }

        public async Task<IEnumerable<Alarm>> GetByAlarmTypeAsync(AlarmType type)
        {
            return await _context.Alarms
                .Where(a => a.AlarmType == type)
                .OrderByDescending(a => a.CreatedAt)
                .ToListAsync();
        }

        public async Task<IEnumerable<Alarm>> GetByStatusAsync(AlarmStatus status)
        {
            return await _context.Alarms
                .Where(a => a.Status == status)
                .OrderByDescending(a => a.CreatedAt)
                .ToListAsync();
        }

        public async Task<IEnumerable<Alarm>> GetByDateRangeAsync(DateTime startDate, DateTime endDate)
        {
            return await _context.Alarms
                .Where(a => a.CreatedAt >= startDate && a.CreatedAt <= endDate)
                .OrderByDescending(a => a.CreatedAt)
                .ToListAsync();
        }

        public async Task<AlarmStatistics> GetAlarmStatisticsAsync(DateTime date)
        {
            var startOfDay = date.Date;
            var endOfDay = startOfDay.AddDays(1);

            var alarms = await _context.Alarms
                .Where(a => a.CreatedAt >= startOfDay && a.CreatedAt <= endOfDay)
                .ToListAsync();

            var stats = new AlarmStatistics
            {
                Date = date,
                TotalAlarms = alarms.Count,
                ActiveAlarms = alarms.Count(a => a.Status == AlarmStatus.Active),
                ResolvedAlarms = alarms.Count(a => a.Status == AlarmStatus.Resolved),
                CriticalAlarms = alarms.Count(a => a.Severity == AlarmSeverity.Critical),
                HighAlarms = alarms.Count(a => a.Severity == AlarmSeverity.High),
                MediumAlarms = alarms.Count(a => a.Severity == AlarmSeverity.Medium),
                LowAlarms = alarms.Count(a => a.Severity == AlarmSeverity.Low),
                DeviceAlarms = alarms.GroupBy(a => a.DeviceId)
                    .ToDictionary(g => g.Key, g => g.Count())
            };

            return stats;
        }

        public async Task<IEnumerable<Alarm>> GetBySeverityAsync(AlarmSeverity severity)
        {
            return await _context.Alarms
                .Where(a => a.Severity == severity)
                .OrderByDescending(a => a.CreatedAt)
                .ToListAsync();
        }

        public async Task<IEnumerable<Alarm>> GetByDeviceAndDateRangeAsync(int deviceId, DateTime startDate, DateTime endDate)
        {
            return await _context.Alarms
                .Where(a => a.DeviceId == deviceId && 
                           a.CreatedAt >= startDate && 
                           a.CreatedAt <= endDate)
                .OrderByDescending(a => a.CreatedAt)
                .ToListAsync();
        }

        public async Task<int> CountActiveAlarmsAsync()
        {
            return await _context.Alarms
                .CountAsync(a => a.Status == AlarmStatus.Active);
        }

        public async Task<IEnumerable<Alarm>> GetActiveAlarmsAsync()
        {
            return await _context.Alarms
                .Where(a => a.Status == AlarmStatus.Active)
                .OrderByDescending(a => a.CreatedAt)
                .ToListAsync();
        }

        public async Task<IEnumerable<Alarm>> GetAlarmsByPriorityAsync(AlarmPriority priority)
        {
            return await _context.Alarms
                .Where(a => a.Priority == priority)
                .OrderByDescending(a => a.CreatedAt)
                .ToListAsync();
        }
    }
}