namespace SimpleAdmin.Application;

/// <summary>
/// 实现基于入职模板创建任务及冻结配置快照的业务能力。
/// </summary>
public class OnboardingTaskService : IOnboardingTaskService
{
    private readonly SqlSugarScope _db;
    private readonly IConfigService _configService;
    private readonly IOnboardingContractSnapshotService _snapshotService;
    private readonly IOnboardingDataPermissionService _dataPermission;

    public OnboardingTaskService(
        IConfigService configService,
        IOnboardingContractSnapshotService snapshotService,
        IOnboardingDataPermissionService dataPermission)
    {
        _db = DbContext.DB;
        _configService = configService;
        _snapshotService = snapshotService;
        _dataPermission = dataPermission;
    }

    /// <summary>
    /// 校验公司、岗位和入职模板后创建任务，并冻结合同及材料要求。
    /// </summary>
    public async Task<OnboardingTaskCreatedOutput> Create(OnboardingTaskCreateInput input)
    {
        if (string.IsNullOrWhiteSpace(input.Remark))
            throw Oops.Bah("请填写人事备注");

        ValidateEmploymentType(input.EmploymentType);

        var companyEnabled = await _db.Queryable<ObCompany>()
            .AnyAsync(item => item.Id == input.CompanyId && item.Status == "enable");
        if (!companyEnabled)
            throw Oops.Bah("公司不存在或未启用");

        var departmentEnabled = await _db.Queryable<ObDepartment>()
            .AnyAsync(item => item.Id == input.DepartmentId && item.CompanyId == input.CompanyId && item.Status == "enable");
        if (!departmentEnabled)
            throw Oops.Bah("部门不存在、未启用或不属于该公司");

        var positionEnabled = await _db.Queryable<ObPosition>()
            .AnyAsync(item => item.Id == input.PositionId
                              && item.CompanyId == input.CompanyId
                              && item.DepartmentId == input.DepartmentId
                              && item.Status == "enable");
        if (!positionEnabled)
            throw Oops.Bah("岗位不存在、未启用或不属于该部门/公司");

        var onboardingTemplate = await _db.Queryable<ObOnboardingTemplate>()
            .FirstAsync(item => item.Id == input.OnboardingTemplateId
                                && item.CompanyId == input.CompanyId
                                && item.DepartmentId == input.DepartmentId
                                && item.Status == "enable")
            ?? throw Oops.Bah("入职模板不存在、未启用或不属于该公司、部门");
        var templateSupportsPosition = await _db.Queryable<ObOnboardingTemplatePosition>()
            .AnyAsync(item => item.OnboardingTemplateId == onboardingTemplate.Id
                              && item.PositionId == input.PositionId);
        if (!templateSupportsPosition)
            throw Oops.Bah("所选入职模板不适用于该岗位");

        var contractConfigs = await _db.Queryable<ObOnboardingTemplateContract>()
            .Where(item => item.OnboardingTemplateId == onboardingTemplate.Id)
            .OrderBy(item => item.SortCode)
            .ToListAsync();
        if (contractConfigs.Count == 0)
            throw Oops.Bah("入职模板尚未配置合同文件");

        var materialConfigs = await _db.Queryable<ObOnboardingTemplateMaterial>()
            .Where(item => item.OnboardingTemplateId == onboardingTemplate.Id)
            .OrderBy(item => item.SortCode)
            .ToListAsync();

        var templateIds = contractConfigs.Select(item => item.ContractTemplateId).Distinct().ToList();
        var contractTemplates = await _db.Queryable<ObContractTemplate>()
            .Where(item => templateIds.Contains(item.Id))
            .ToListAsync();
        if (contractTemplates.Count != templateIds.Count
            || contractTemplates.Any(item => item.CompanyId != input.CompanyId
                                             || item.DepartmentId != input.DepartmentId
                                             || !string.Equals(
                                                 item.Status,
                                                 "enable",
                                                 global::System.StringComparison.OrdinalIgnoreCase)))
        {
            throw Oops.Bah("入职模板包含未启用或不属于当前公司、部门的合同模板");
        }

        var contractPositionCount = await _db.Queryable<ObContractTemplatePosition>()
            .CountAsync(item => templateIds.Contains(item.ContractTemplateId)
                                && item.PositionId == input.PositionId);
        if (contractPositionCount != templateIds.Count)
            throw Oops.Bah("入职模板包含不适用于当前岗位的合同模板");

        var versionIds = contractConfigs.Select(item => item.ContractTemplateVersionId).Distinct().ToList();
        var enabledVersionCount = await _db.Queryable<ObContractTemplateVersion>()
            .CountAsync(item => versionIds.Contains(item.Id)
                                && item.VersionStatus == ContractTemplateVersionStatus.Enabled);
        if (enabledVersionCount != versionIds.Count)
            throw Oops.Bah("入职模板包含未启用的合同版本，请先调整模板配置");

        var materialIds = materialConfigs.Select(item => item.MaterialTypeId).Distinct().ToList();
        var materialTypes = materialIds.Count == 0
            ? new List<ObMaterialType>()
            : await _db.Queryable<ObMaterialType>().Where(item => materialIds.Contains(item.Id)).ToListAsync();
        if (materialTypes.Count != materialIds.Count)
            throw Oops.Bah("入职模板包含不存在的材料类型，请先调整模板配置");

        var expiryConfig = await _configService.GetByConfigKey(
            CateGoryConst.CONFIG_BIZ_DEFINE,
            "onboard.link.expireHours");
        if (expiryConfig == null
            || !int.TryParse(expiryConfig.ConfigValue, out var expiryHours)
            || expiryHours <= 0)
        {
            throw Oops.Bah("请在系统配置中设置 onboard.link.expireHours（正整数小时）");
        }

        var taskId = global::SimpleAdmin.Core.Utils.CommonUtils.GetSingleId();
        var expiresAt = DateTime.Now.AddHours(expiryHours);
        var token = Guid.NewGuid().ToString("N");
        var task = new ObOnboardingTask
        {
            Id = taskId,
            TaskNo = $"OB{DateTime.Now:yyyyMMddHHmmss}{taskId.ToString()[^4..]}",
            CompanyId = input.CompanyId,
            DepartmentId = input.DepartmentId,
            PositionId = input.PositionId,
            EmploymentType = input.EmploymentType,
            OnboardingTemplateId = onboardingTemplate.Id,
            AssignedReviewerUserId = input.AssignedReviewerUserId,
            LinkExpireAt = expiresAt,
            TaskStatus = OnboardingTaskStatus.PendingFill,
            Remark = input.Remark.Trim()
        };

        ValidateInitialContractDateRanges(input.ContractVariables);

        await _db.Ado.BeginTranAsync();
        try
        {
            await _db.Insertable(task).ExecuteCommandAsync();
            await _db.Insertable(new ObTaskLink
            {
                Id = global::SimpleAdmin.Core.Utils.CommonUtils.GetSingleId(),
                TaskId = taskId,
                PlainToken = token,
                TokenHash = Convert.ToHexString(global::System.Security.Cryptography.SHA256.HashData(
                    global::System.Text.Encoding.UTF8.GetBytes(token))),
                ExpiresAt = expiresAt
            }).ExecuteCommandAsync();

            // 初始化空白的员工入职登记表
            await _db.Insertable(new ObTaskEmployeeInfo
            {
                Id = global::SimpleAdmin.Core.Utils.CommonUtils.GetSingleId(),
                TaskId = taskId,
                Status = CommonStatusConst.ENABLE,
                CreateTime = DateTime.Now
            }).ExecuteCommandAsync();

            var contracts = contractConfigs.Select(config =>
            {
                var template = contractTemplates.First(item => item.Id == config.ContractTemplateId);
                return new ObTaskContract
                {
                    Id = global::SimpleAdmin.Core.Utils.CommonUtils.GetSingleId(),
                    TaskId = taskId,
                    TemplateId = config.ContractTemplateId,
                    TemplateVersionId = config.ContractTemplateVersionId,
                    ContractName = template.TemplateName,
                    ContractType = template.ContractType,
                    Required = config.Required,
                    PrintCopies = config.PrintCopies
                };
            }).ToList();
            await _db.Insertable(contracts).ExecuteCommandAsync();

            if (materialConfigs.Count > 0)
            {
                var materialSnapshots = materialConfigs.Select(config =>
                {
                    var material = materialTypes.First(item => item.Id == config.MaterialTypeId);
                    return new ObTaskMaterialRequirement
                    {
                        Id = global::SimpleAdmin.Core.Utils.CommonUtils.GetSingleId(),
                        TaskId = taskId,
                        MaterialTypeId = material.Id,
                        MaterialCode = material.MaterialCode,
                        MaterialName = material.MaterialName,
                        AllowedExtensions = material.AllowedExtensions,
                        MaxFileCount = material.MaxFileCount,
                        MaxFileSizeMb = material.MaxFileSizeMb,
                        Required = config.Required,
                        SortCode = config.SortCode
                    };
                }).ToList();
                await _db.Insertable(materialSnapshots).ExecuteCommandAsync();
            }

            await _snapshotService.Build(taskId);
            await ApplyInitialContractVariables(input.ContractVariables, contracts);
            await _db.Ado.CommitTranAsync();
        }
        catch
        {
            await _db.Ado.RollbackTranAsync();
            throw;
        }

        return new OnboardingTaskCreatedOutput
        {
            TaskId = taskId,
            TaskNo = task.TaskNo,
            LinkToken = token,
            ExpiresAt = expiresAt
        };
    }

    /// <summary>
    /// 复制原任务锁定的业务配置与人事参数，并原子化创建多条独立任务。
    /// </summary>
    public async Task<OnboardingTaskCopyOutput> Copy(OnboardingTaskCopyInput input)
    {
        const int maxCopyCount = 50;
        if (input.Count < 1 || input.Count > maxCopyCount)
            throw Oops.Bah($"复制数量必须在1到{maxCopyCount}之间");

        input.Items ??= new List<OnboardingTaskCopyItemInput>();
        if (input.Items.Count != input.Count)
            throw Oops.Bah("复制数量与人事备注数量不一致");

        var missingRemarkIndex = input.Items.FindIndex(item =>
            string.IsNullOrWhiteSpace(item.Remark));
        if (missingRemarkIndex >= 0)
            throw Oops.Bah($"请填写第{missingRemarkIndex + 1}份任务的人事备注");

        var sourceTask = await _db.Queryable<ObOnboardingTask>()
            .InSingleAsync(input.SourceTaskId)
            ?? throw Oops.Bah("原入职任务不存在");
        await _dataPermission.EnsureCanManage(
            sourceTask.CreateUserId,
            OnboardingPermissionCodes.TaskManageAll,
            "入职任务");
        if (!sourceTask.DepartmentId.HasValue)
            throw Oops.Bah("原入职任务未设置部门，不能复制");

        var companyEnabled = await _db.Queryable<ObCompany>()
            .AnyAsync(item => item.Id == sourceTask.CompanyId && item.Status == "enable");
        if (!companyEnabled)
            throw Oops.Bah("原任务所属公司不存在或未启用");

        var departmentEnabled = await _db.Queryable<ObDepartment>()
            .AnyAsync(item => item.Id == sourceTask.DepartmentId.Value
                              && item.CompanyId == sourceTask.CompanyId
                              && item.Status == "enable");
        if (!departmentEnabled)
            throw Oops.Bah("原任务所属部门不存在或未启用");

        var positionEnabled = await _db.Queryable<ObPosition>()
            .AnyAsync(item => item.Id == sourceTask.PositionId
                              && item.CompanyId == sourceTask.CompanyId
                              && item.DepartmentId == sourceTask.DepartmentId.Value
                              && item.Status == "enable");
        if (!positionEnabled)
            throw Oops.Bah("原任务所属岗位不存在或未启用");

        var onboardingTemplateEnabled = await _db.Queryable<ObOnboardingTemplate>()
            .AnyAsync(item => item.Id == sourceTask.OnboardingTemplateId
                              && item.CompanyId == sourceTask.CompanyId
                              && item.DepartmentId == sourceTask.DepartmentId.Value
                              && item.Status == "enable");
        if (!onboardingTemplateEnabled)
            throw Oops.Bah("原任务使用的入职模板不存在或未启用");

        var sourceContracts = await _db.Queryable<ObTaskContract>()
            .Where(item => item.TaskId == sourceTask.Id)
            .ToListAsync();
        if (sourceContracts.Count == 0)
            throw Oops.Bah("原入职任务没有合同快照，不能复制");

        var versionIds = sourceContracts
            .Select(item => item.TemplateVersionId)
            .Distinct()
            .ToList();
        var enabledVersionCount = await _db.Queryable<ObContractTemplateVersion>()
            .CountAsync(item => versionIds.Contains(item.Id)
                                && item.VersionStatus == ContractTemplateVersionStatus.Enabled);
        if (enabledVersionCount != versionIds.Count)
            throw Oops.Bah("原任务包含已停用的合同版本，不能继续复制");

        var sourceMaterialRequirements = await _db.Queryable<ObTaskMaterialRequirement>()
            .Where(item => item.TaskId == sourceTask.Id)
            .OrderBy(item => item.SortCode)
            .ToListAsync();
        var sourceContractIds = sourceContracts.Select(item => item.Id).ToList();
        var sourceManualVariables = await _db.Queryable<ObTaskContractVariable>()
            .Where(item => sourceContractIds.Contains(item.TaskContractId)
                           && item.SourceType == ContractVariableSourceType.HrInput
                           && item.IsManualOverride)
            .ToListAsync();

        var initialContractVariables = (
            from contract in sourceContracts
            join variable in sourceManualVariables
                on contract.Id equals variable.TaskContractId
            select new OnboardingInitialContractVariableInput
            {
                ContractTemplateVersionId = contract.TemplateVersionId,
                VariableCode = variable.VariableCode,
                VariableValue = variable.VariableValue
            }).ToList();
        ValidateInitialContractDateRanges(initialContractVariables);

        var expiryConfig = await _configService.GetByConfigKey(
            CateGoryConst.CONFIG_BIZ_DEFINE,
            "onboard.link.expireHours");
        if (expiryConfig == null
            || !int.TryParse(expiryConfig.ConfigValue, out var expiryHours)
            || expiryHours <= 0)
        {
            throw Oops.Bah("请在系统配置中设置 onboard.link.expireHours（正整数小时）");
        }

        var outputs = new List<OnboardingTaskCreatedOutput>();
        await _db.Ado.BeginTranAsync();
        try
        {
            foreach (var item in input.Items)
            {
                var output = await CreateCopiedTask(
                    sourceTask,
                    sourceContracts,
                    sourceMaterialRequirements,
                    initialContractVariables,
                    expiryHours,
                    item.Remark.Trim());
                outputs.Add(output);
            }

            await _db.Ado.CommitTranAsync();
        }
        catch
        {
            await _db.Ado.RollbackTranAsync();
            throw;
        }

        return new OnboardingTaskCopyOutput
        {
            Tasks = outputs
        };
    }

    /// <summary>
    /// 根据原任务快照创建一条全新的待填写任务，不复制任何候选人业务数据。
    /// </summary>
    private async Task<OnboardingTaskCreatedOutput> CreateCopiedTask(
        ObOnboardingTask sourceTask,
        List<ObTaskContract> sourceContracts,
        List<ObTaskMaterialRequirement> sourceMaterialRequirements,
        List<OnboardingInitialContractVariableInput> initialContractVariables,
        int expiryHours,
        string remark)
    {
        var now = DateTime.Now;
        var taskId = global::SimpleAdmin.Core.Utils.CommonUtils.GetSingleId();
        var expiresAt = now.AddHours(expiryHours);
        var token = Guid.NewGuid().ToString("N");
        var task = new ObOnboardingTask
        {
            Id = taskId,
            TaskNo = $"OB{now:yyyyMMddHHmmss}{taskId.ToString()[^4..]}",
            CompanyId = sourceTask.CompanyId,
            DepartmentId = sourceTask.DepartmentId,
            PositionId = sourceTask.PositionId,
            EmploymentType = string.IsNullOrWhiteSpace(sourceTask.EmploymentType)
                ? EmployeeEmploymentType.FullTime
                : sourceTask.EmploymentType,
            OnboardingTemplateId = sourceTask.OnboardingTemplateId,
            AssignedReviewerUserId = sourceTask.AssignedReviewerUserId,
            LinkExpireAt = expiresAt,
            TaskStatus = OnboardingTaskStatus.PendingFill,
            Remark = remark
        };

        await _db.Insertable(task).ExecuteCommandAsync();
        await _db.Insertable(new ObTaskLink
        {
            Id = global::SimpleAdmin.Core.Utils.CommonUtils.GetSingleId(),
            TaskId = taskId,
            PlainToken = token,
            TokenHash = Convert.ToHexString(global::System.Security.Cryptography.SHA256.HashData(
                global::System.Text.Encoding.UTF8.GetBytes(token))),
            ExpiresAt = expiresAt
        }).ExecuteCommandAsync();

        await _db.Insertable(new ObTaskEmployeeInfo
        {
            Id = global::SimpleAdmin.Core.Utils.CommonUtils.GetSingleId(),
            TaskId = taskId,
            Status = CommonStatusConst.ENABLE,
            CreateTime = now
        }).ExecuteCommandAsync();

        var copiedContracts = sourceContracts.Select(source => new ObTaskContract
        {
            Id = global::SimpleAdmin.Core.Utils.CommonUtils.GetSingleId(),
            TaskId = taskId,
            TemplateId = source.TemplateId,
            TemplateVersionId = source.TemplateVersionId,
            ContractName = source.ContractName,
            ContractType = source.ContractType,
            Required = source.Required,
            PrintCopies = source.PrintCopies
        }).ToList();
        await _db.Insertable(copiedContracts).ExecuteCommandAsync();

        if (sourceMaterialRequirements.Count > 0)
        {
            var copiedRequirements = sourceMaterialRequirements.Select(source =>
                new ObTaskMaterialRequirement
                {
                    Id = global::SimpleAdmin.Core.Utils.CommonUtils.GetSingleId(),
                    TaskId = taskId,
                    MaterialTypeId = source.MaterialTypeId,
                    MaterialCode = source.MaterialCode,
                    MaterialName = source.MaterialName,
                    AllowedExtensions = source.AllowedExtensions,
                    MaxFileCount = source.MaxFileCount,
                    MaxFileSizeMb = source.MaxFileSizeMb,
                    Required = source.Required,
                    SortCode = source.SortCode
                }).ToList();
            await _db.Insertable(copiedRequirements).ExecuteCommandAsync();
        }

        // 重新生成公司、系统和空员工变量，再覆盖原任务的人事参数。
        await _snapshotService.Build(taskId);
        await ApplyInitialContractVariables(initialContractVariables, copiedContracts);

        return new OnboardingTaskCreatedOutput
        {
            TaskId = taskId,
            TaskNo = task.TaskNo,
            LinkToken = token,
            ExpiresAt = expiresAt
        };
    }

    /// <summary>
    /// 校验并保存任务创建时填写的人事合同变量。
    /// </summary>
    private async Task ApplyInitialContractVariables(
        List<OnboardingInitialContractVariableInput> inputs,
        List<ObTaskContract> contracts)
    {
        inputs ??= new List<OnboardingInitialContractVariableInput>();
        var versionIds = contracts.Select(item => item.TemplateVersionId).Distinct().ToList();
        var definitions = await _db.Queryable<ObTemplateVariable>()
            .Where(item => versionIds.Contains(item.TemplateVersionId)
                           && item.HrEditable
                           && (item.VariableType == "hr"
                               || item.VariableType == "contract"
                               || item.VariableType == "company"
                               || item.VariableType == ContractVariableType.Contract
                               || item.VariableType == ContractVariableType.Company
                               || item.VariableCode.StartsWith("hr.")))
            .ToListAsync();

        var duplicateInput = inputs
            .GroupBy(item => new { item.ContractTemplateVersionId, item.VariableCode })
            .FirstOrDefault(group => group.Count() > 1);
        if (duplicateInput != null)
            throw Oops.Bah($"合同变量“{duplicateInput.Key.VariableCode}”重复提交");

        foreach (var input in inputs)
        {
            var definitionExists = definitions.Any(item =>
                item.TemplateVersionId == input.ContractTemplateVersionId
                && item.VariableCode == input.VariableCode);
            if (!definitionExists)
                throw Oops.Bah($"合同变量“{input.VariableCode}”不存在或不允许人事填写");
        }

        var missingRequired = definitions.FirstOrDefault(definition =>
        {
            if (!definition.Required)
                return false;

            var input = inputs.FirstOrDefault(item =>
                item.ContractTemplateVersionId == definition.TemplateVersionId
                && item.VariableCode == definition.VariableCode);
            return string.IsNullOrWhiteSpace(input?.VariableValue ?? definition.DefaultValue);
        });
        if (missingRequired != null)
            throw Oops.Bah($"请填写合同变量“{missingRequired.VariableName}”");

        if (inputs.Count == 0)
            return;

        var duplicateContractVersion = contracts
            .GroupBy(item => item.TemplateVersionId)
            .FirstOrDefault(group => group.Count() > 1);
        if (duplicateContractVersion != null)
            throw Oops.Bah("入职模板中存在重复的合同版本，请重新保存入职模板后再创建任务");

        var contractByVersion = contracts.ToDictionary(item => item.TemplateVersionId);
        var contractIds = contracts.Select(item => item.Id).ToList();
        var rows = await _db.Queryable<ObTaskContractVariable>()
            .Where(item => contractIds.Contains(item.TaskContractId))
            .ToListAsync();

        foreach (var input in inputs)
        {
            var contract = contractByVersion[input.ContractTemplateVersionId];
            var row = rows.FirstOrDefault(item =>
                item.TaskContractId == contract.Id && item.VariableCode == input.VariableCode)
                ?? throw Oops.Bah($"合同变量快照“{input.VariableCode}”不存在");
            row.VariableValue = input.VariableValue;
            row.SourceType = ContractVariableSourceType.HrInput;
            row.IsManualOverride = true;
        }

        var changedRows = rows.Where(item => item.IsManualOverride).ToList();
        if (changedRows.Count > 0)
            await _db.Updateable(changedRows).ExecuteCommandAsync();
    }

    /// <summary>
    /// 校验人事创建任务时填写的合同日期先后关系。
    /// </summary>
    internal static void ValidateInitialContractDateRanges(
        List<OnboardingInitialContractVariableInput> inputs)
    {
        inputs ??= new List<OnboardingInitialContractVariableInput>();
        foreach (var group in inputs.GroupBy(item => item.ContractTemplateVersionId))
        {
            ValidateDateRange(group, "hr.ContractStartDate", "hr.ContractEndDate", "合同");
            ValidateDateRange(group, "hr.ProbationStartDate", "hr.ProbationEndDate", "试用期");
        }
    }

    /// <summary>
    /// 校验同一合同版本内一组开始、结束日期。
    /// </summary>
    private static void ValidateDateRange(
        IEnumerable<OnboardingInitialContractVariableInput> inputs,
        string startCode,
        string endCode,
        string rangeName)
    {
        var startValue = inputs.FirstOrDefault(item =>
            string.Equals(item.VariableCode, startCode, StringComparison.OrdinalIgnoreCase))?.VariableValue;
        var endValue = inputs.FirstOrDefault(item =>
            string.Equals(item.VariableCode, endCode, StringComparison.OrdinalIgnoreCase))?.VariableValue;
        if (string.IsNullOrWhiteSpace(startValue) || string.IsNullOrWhiteSpace(endValue))
            return;

        if (!DateTime.TryParse(startValue, out var startDate))
            throw Oops.Bah($"{rangeName}开始日期格式不正确");
        if (!DateTime.TryParse(endValue, out var endDate))
            throw Oops.Bah($"{rangeName}结束日期格式不正确");
        if (endDate.Date < startDate.Date)
            throw Oops.Bah($"{rangeName}结束日期不能早于开始日期");
    }

    private static void ValidateEmploymentType(string employmentType)
    {
        if (employmentType != EmployeeEmploymentType.FullTime
            && employmentType != EmployeeEmploymentType.PartTime)
        {
            throw Oops.Bah("用工类型不正确，请选择正式员工或兼职员工");
        }
    }
}