using System;
using System.Collections.Generic;
using Notesnook.API.Models;
using Streetwriters.Common.Enums;
using Streetwriters.Common.Models;

namespace Notesnook.API.Helpers
{
    class StorageHelper
    {
        const long MB = 1024 * 1024;
        const long GB = 1024 * MB;
        public readonly static Dictionary<SubscriptionPlan, long> MAX_STORAGE_PER_MONTH = new()
            {
                { SubscriptionPlan.FREE, 50L * MB },
                { SubscriptionPlan.ESSENTIAL, GB },
                { SubscriptionPlan.PRO, 10L * GB },
                { SubscriptionPlan.EDUCATION, 10L * GB },
                { SubscriptionPlan.BELIEVER, 25L * GB },
                { SubscriptionPlan.LEGACY_PRO, -1 }
            };
        public readonly static Dictionary<SubscriptionPlan, long> MAX_FILE_SIZE = new()
            {
                { SubscriptionPlan.FREE, 10 * MB },
                { SubscriptionPlan.ESSENTIAL, 100 * MB },
                { SubscriptionPlan.PRO, 1L * GB },
                { SubscriptionPlan.EDUCATION, 1L * GB },
                { SubscriptionPlan.BELIEVER, 5L * GB },
                { SubscriptionPlan.LEGACY_PRO, 512 * MB }
            };

        public static long GetStorageLimitForPlan(Subscription subscription)
        {
            return MAX_STORAGE_PER_MONTH[subscription.Plan];
        }

        public static long GetFileSizeLimitForPlan(Subscription subscription)
        {
            return MAX_FILE_SIZE[subscription.Plan];
        }

        public static bool IsStorageLimitReached(Subscription subscription, long limit)
        {
            var storageLimit = GetStorageLimitForPlan(subscription);
            if (storageLimit == -1) return false;
            return limit > storageLimit;
        }

        public static bool IsFileSizeExceeded(Subscription subscription, long fileSize)
        {
            var maxFileSize = MAX_FILE_SIZE[subscription.Plan];
            return fileSize > maxFileSize;
        }

        public static Limit RolloverStorageLimit(Limit? limit)
        {
            var updatedAt = DateTimeOffset.FromUnixTimeMilliseconds(limit?.UpdatedAt ?? 0);
            if (limit == null || DateTimeOffset.UtcNow.Year > updatedAt.Year || DateTimeOffset.UtcNow.Month > updatedAt.Month)
            {
                limit = new Limit { UpdatedAt = DateTimeOffset.UtcNow.ToUnixTimeMilliseconds(), Value = 0 };
                return limit;
            }
            return limit;
        }

        private static readonly string[] sizes = ["B", "KB", "MB", "GB", "TB"];
        public static string FormatBytes(long size)
        {
            int order = 0;
            while (size >= 1024 && order < sizes.Length - 1)
            {
                order++;
                size = size / 1024;
            }

            return String.Format("{0:0.##} {1}", size, sizes[order]);
        }
    }
}