using Data.SeaHavenIndustries;
using Data.SeaHavenIndustries.Enums;
using SeaHaven.Services.Constants;
using SeaHaven.Services.Interfaces;

namespace SeaHaven.Services.Implementation
{
    public class SyncFieldMergePolicy : ISyncFieldMergePolicy
    {
        private static readonly HashSet<string> ShocOwnedFieldSet = new(StringComparer.OrdinalIgnoreCase)
        {
            WorkOrderFieldNames.LifecycleStatus,
            WorkOrderFieldNames.AssignTo,
            WorkOrderFieldNames.ScheduledDate,
            WorkOrderFieldNames.ScheduledStart,
            WorkOrderFieldNames.ScheduledEnd,
            WorkOrderFieldNames.TargetWeek,
            WorkOrderFieldNames.ScheduleWeekOnly,
            WorkOrderFieldNames.DueDate,
            WorkOrderFieldNames.Description,
            WorkOrderFieldNames.WorkerOrderTitle,
            WorkOrderFieldNames.SiteCode,
            WorkOrderFieldNames.Building,
            WorkOrderFieldNames.LocationId,
            WorkOrderFieldNames.WorkOrderType,
            WorkOrderFieldNames.Service,
            WorkOrderFieldNames.DocStatus,
            WorkOrderFieldNames.Trade,
            WorkOrderFieldNames.Problem,
            WorkOrderFieldNames.Priority,
            WorkOrderFieldNames.InternalWONumber,
            WorkOrderFieldNames.Status,
        };

        private readonly IWorkOrderFieldLockService _fieldLocks;

        public SyncFieldMergePolicy(IWorkOrderFieldLockService fieldLocks)
        {
            _fieldLocks = fieldLocks;
        }

        public IReadOnlySet<string> ShocOwnedFields => ShocOwnedFieldSet;

        public async Task<bool> CanSyncOverwriteAsync(int workOrderId, string fieldName)
            => !await _fieldLocks.IsLockedAsync(workOrderId, fieldName);

        public async Task<bool> TryApplyAsync(WorkOrderSyncContext context, string fieldName, object? incomingValue)
        {
            if (incomingValue == null) return false;

            if (await context.FieldLocks.IsLockedAsync(context.WorkOrder.Id, fieldName))
            {
                var current = GetFieldValue(context.WorkOrder, fieldName);
                await context.Audit.LogSyncRejectedAsync(
                    context.WorkOrder.Id,
                    fieldName,
                    current,
                    incomingValue.ToString());
                return false;
            }

            return TryApplyField(context.WorkOrder, fieldName, incomingValue);
        }

        private static string? GetFieldValue(WorkOrder wo, string fieldName) => fieldName switch
        {
            WorkOrderFieldNames.Description => wo.Description,
            WorkOrderFieldNames.WorkerOrderTitle => wo.WorkerOrderTitle,
            WorkOrderFieldNames.Status => wo.Status,
            WorkOrderFieldNames.DueDate => wo.DueDate?.ToString("O"),
            WorkOrderFieldNames.ScheduledDate => wo.ScheduledDate?.ToString("O"),
            WorkOrderFieldNames.ScheduledStart => wo.ScheduledStart?.ToString("O"),
            WorkOrderFieldNames.ScheduledEnd => wo.ScheduledEnd?.ToString("O"),
            WorkOrderFieldNames.TargetWeek => wo.TargetWeek?.ToString("O"),
            WorkOrderFieldNames.ScheduleWeekOnly => wo.ScheduleWeekOnly?.ToString(),
            WorkOrderFieldNames.SiteCode => wo.SiteCode,
            WorkOrderFieldNames.Building => wo.Building,
            WorkOrderFieldNames.Priority => wo.Priority,
            WorkOrderFieldNames.AssignTo => wo.AssignTo,
            WorkOrderFieldNames.LocationId => wo.LocationId?.ToString(),
            WorkOrderFieldNames.LifecycleStatus => wo.LifecycleStatus?.ToString(),
            WorkOrderFieldNames.WorkOrderType => wo.WorkOrderType?.ToString(),
            WorkOrderFieldNames.Service => wo.Service,
            WorkOrderFieldNames.DocStatus => wo.DocStatus?.ToString(),
            WorkOrderFieldNames.Trade => wo.Trade,
            WorkOrderFieldNames.Problem => wo.Problem,
            WorkOrderFieldNames.InternalWONumber => wo.InternalWONumber,
            _ => null
        };

        private static bool TryApplyField(WorkOrder wo, string fieldName, object incomingValue)
        {
            switch (fieldName)
            {
                case WorkOrderFieldNames.Description:
                    wo.Description = incomingValue.ToString();
                    return true;
                case WorkOrderFieldNames.WorkerOrderTitle:
                    wo.WorkerOrderTitle = incomingValue.ToString();
                    return true;
                case WorkOrderFieldNames.Status:
                    wo.Status = incomingValue.ToString();
                    return true;
                case WorkOrderFieldNames.DueDate when TryParseDateTime(incomingValue, out var dueDate):
                    wo.DueDate = dueDate;
                    return true;
                case WorkOrderFieldNames.ScheduledDate when TryParseDateTime(incomingValue, out var scheduledDate):
                    wo.ScheduledDate = scheduledDate;
                    return true;
                case WorkOrderFieldNames.ScheduledStart when TryParseDateTime(incomingValue, out var scheduledStart):
                    wo.ScheduledStart = scheduledStart;
                    return true;
                case WorkOrderFieldNames.ScheduledEnd when TryParseDateTime(incomingValue, out var scheduledEnd):
                    wo.ScheduledEnd = scheduledEnd;
                    return true;
                case WorkOrderFieldNames.TargetWeek when TryParseDateOnly(incomingValue, out var targetWeek):
                    wo.TargetWeek = targetWeek;
                    return true;
                case WorkOrderFieldNames.ScheduleWeekOnly when TryParseBool(incomingValue, out var scheduleWeekOnly):
                    wo.ScheduleWeekOnly = scheduleWeekOnly;
                    return true;
                case WorkOrderFieldNames.SiteCode:
                    wo.SiteCode = incomingValue.ToString();
                    return true;
                case WorkOrderFieldNames.Building:
                    wo.Building = incomingValue.ToString();
                    return true;
                case WorkOrderFieldNames.Priority:
                    wo.Priority = incomingValue.ToString();
                    return true;
                case WorkOrderFieldNames.AssignTo:
                    wo.AssignTo = incomingValue.ToString();
                    return true;
                case WorkOrderFieldNames.LocationId when TryParseInt(incomingValue, out var locationId):
                    wo.LocationId = locationId;
                    return true;
                case WorkOrderFieldNames.LifecycleStatus when TryParseEnum(incomingValue, out LifecycleStatus lifecycleStatus):
                    wo.LifecycleStatus = lifecycleStatus;
                    return true;
                case WorkOrderFieldNames.WorkOrderType when TryParseEnum(incomingValue, out WorkOrderType workOrderType):
                    wo.WorkOrderType = workOrderType;
                    return true;
                case WorkOrderFieldNames.Service:
                    wo.Service = incomingValue.ToString();
                    return true;
                case WorkOrderFieldNames.DocStatus when TryParseEnum(incomingValue, out DocStatus docStatus):
                    wo.DocStatus = docStatus;
                    return true;
                case WorkOrderFieldNames.Trade:
                    wo.Trade = incomingValue.ToString();
                    return true;
                case WorkOrderFieldNames.Problem:
                    wo.Problem = incomingValue.ToString();
                    return true;
                case WorkOrderFieldNames.InternalWONumber:
                    wo.InternalWONumber = incomingValue.ToString();
                    return true;
                default:
                    return false;
            }
        }

        private static bool TryParseDateTime(object value, out DateTime result)
        {
            if (value is DateTime dt)
            {
                result = dt;
                return true;
            }

            return DateTime.TryParse(value.ToString(), out result);
        }

        private static bool TryParseDateOnly(object value, out DateOnly result)
        {
            if (value is DateOnly dateOnly)
            {
                result = dateOnly;
                return true;
            }

            if (value is DateTime dt)
            {
                result = DateOnly.FromDateTime(dt);
                return true;
            }

            return DateOnly.TryParse(value.ToString(), out result);
        }

        private static bool TryParseBool(object value, out bool result)
        {
            if (value is bool b)
            {
                result = b;
                return true;
            }

            return bool.TryParse(value.ToString(), out result);
        }

        private static bool TryParseInt(object value, out int result)
        {
            if (value is int i)
            {
                result = i;
                return true;
            }

            return int.TryParse(value.ToString(), out result);
        }

        private static bool TryParseEnum<TEnum>(object value, out TEnum result) where TEnum : struct, Enum
        {
            if (value is TEnum enumValue)
            {
                result = enumValue;
                return true;
            }

            return Enum.TryParse(value.ToString(), true, out result);
        }
    }
}