# payslips/serializers.py from rest_framework import serializers from django.db import models from django.utils import timezone from django.db import IntegrityError from decimal import Decimal from people.models import Teacher from people.serializers import SimpleTeacherSerializer from .models import ( TeacherPayStructure, MonthlyPaySlip, PaymentTransaction, PaySlipTemplate ) # ===================================================== # TEACHER PAY STRUCTURE SERIALIZERS # ===================================================== class TeacherPayStructureSerializer(serializers.ModelSerializer): """Complete Teacher Pay Structure Serializer""" teacher_name = serializers.CharField(source='teacher.full_name', read_only=True) teacher_employee_id = serializers.CharField(source='teacher.employee_id', read_only=True) created_by_name = serializers.CharField(source='created_by.full_name', read_only=True, default=None) total_monthly_fixed_earnings = serializers.DecimalField( max_digits=12, decimal_places=2, read_only=True ) class Meta: model = TeacherPayStructure fields = [ 'id', 'teacher', 'teacher_name', 'teacher_employee_id', 'effective_from', 'effective_to', 'base_salary', 'dearness_allowance', 'house_rent_allowance', 'city_compensatory_allowance', 'travel_allowance', 'medical_allowance', 'special_allowance', 'education_allowance', 'telephone_allowance', 'provident_fund_percentage', 'esi_percentage', 'professional_tax_fixed', 'default_performance_incentive', 'default_special_class_incentive', 'default_subject_expert_incentive', 'default_leadership_allowance', 'total_monthly_fixed_earnings', 'is_active', 'created_by', 'created_by_name', 'created_at', 'updated_at', ] read_only_fields = ['created_at', 'updated_at'] def validate_teacher(self, value): """Ensure teacher doesn't already have an active pay structure""" if not self.instance: existing = TeacherPayStructure.objects.filter( teacher=value, is_active=True ).first() if existing: raise serializers.ValidationError( f"Teacher already has an active pay structure. " f"Deactivate the existing one first." ) return value def validate(self, data): """Validate effective dates""" effective_from = data.get('effective_from') effective_to = data.get('effective_to') if effective_from and effective_to and effective_from > effective_to: raise serializers.ValidationError( "Effective from date cannot be after effective to date" ) return data class TeacherPayStructureListSerializer(serializers.ModelSerializer): """List view Teacher Pay Structure Serializer with all fields""" teacher_name = serializers.CharField(source='teacher.full_name', read_only=True) teacher_employee_id = serializers.CharField(source='teacher.employee_id', read_only=True) created_by_name = serializers.CharField(source='created_by.full_name', read_only=True, default=None) total_monthly_fixed_earnings = serializers.DecimalField( max_digits=12, decimal_places=2, read_only=True ) class Meta: model = TeacherPayStructure fields = [ 'id', 'teacher', 'teacher_name', 'teacher_employee_id', 'effective_from', 'effective_to', 'base_salary', 'dearness_allowance', 'house_rent_allowance', 'city_compensatory_allowance', 'travel_allowance', 'medical_allowance', 'special_allowance', 'education_allowance', 'telephone_allowance', 'provident_fund_percentage', 'esi_percentage', 'professional_tax_fixed', 'default_performance_incentive', 'default_special_class_incentive', 'default_subject_expert_incentive', 'default_leadership_allowance', 'total_monthly_fixed_earnings', 'is_active', 'created_by', 'created_by_name', 'created_at', 'updated_at', ] # ===================================================== # MONTHLY PAY SLIP SERIALIZERS # ===================================================== class MonthlyPaySlipSerializer(serializers.ModelSerializer): """Base Monthly Pay Slip Serializer""" teacher_name = serializers.CharField(source='teacher.full_name', read_only=True) teacher_employee_id = serializers.CharField(source='teacher.employee_id', read_only=True) created_by_name = serializers.CharField(source='created_by.full_name', read_only=True, default=None) approved_by_name = serializers.CharField(source='approved_by.full_name', read_only=True, default=None) month_name = serializers.SerializerMethodField() class Meta: model = MonthlyPaySlip fields = [ 'id', 'pay_slip_number', 'teacher', 'teacher_name', 'teacher_employee_id', 'month', 'month_name', 'year', 'status', 'base_salary', 'dearness_allowance', 'house_rent_allowance', 'city_compensatory_allowance', 'travel_allowance', 'medical_allowance', 'special_allowance', 'education_allowance', 'telephone_allowance', 'performance_incentive', 'special_class_incentive', 'subject_expert_incentive', 'leadership_allowance', 'festival_bonus', 'annual_bonus', 'overtime_allowance', 'variable_pay', 'additional_earnings', 'other_allowances', 'provident_fund_employee', 'provident_fund_employer', 'esi_deduction', 'professional_tax', 'income_tax', 'loan_deduction', 'advance_deduction', 'attendance_deduction', 'other_deductions', 'casual_leave_taken', 'sick_leave_taken', 'earned_leave_taken', 'unpaid_leave_days', 'total_working_days', 'days_present', 'days_absent', 'late_days', 'total_earnings', 'total_deductions', 'net_pay', 'remarks', 'hr_remarks', 'created_by', 'created_by_name', 'approved_by', 'approved_by_name', 'approved_at', 'is_acknowledged', 'acknowledged_at', 'created_at', 'updated_at', ] read_only_fields = ['pay_slip_number', 'created_at', 'updated_at', 'total_earnings', 'total_deductions', 'net_pay'] def get_month_name(self, obj): """Get month name""" months = [ 'January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December' ] return months[obj.month - 1] if 1 <= obj.month <= 12 else str(obj.month) def validate(self, data): """Validate month and year uniqueness""" teacher = data.get('teacher') month = data.get('month') year = data.get('year') if not self.instance: existing = MonthlyPaySlip.objects.filter( teacher=teacher, month=month, year=year, is_active=True ).first() if existing: raise serializers.ValidationError( f"Pay slip already exists for {month}/{year}" ) return data class MonthlyPaySlipListSerializer(serializers.ModelSerializer): """List view Monthly Pay Slip Serializer""" teacher_name = serializers.CharField(source='teacher.full_name', read_only=True) teacher_employee_id = serializers.CharField(source='teacher.employee_id', read_only=True) month_name = serializers.SerializerMethodField() total_paid = serializers.SerializerMethodField() class Meta: model = MonthlyPaySlip fields = [ 'id', 'pay_slip_number', 'teacher', 'teacher_name', 'teacher_employee_id', 'month', 'month_name', 'year', 'status', 'net_pay', 'total_paid', 'is_acknowledged', 'created_at', ] def get_month_name(self, obj): months = [ 'January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December' ] return months[obj.month - 1] if 1 <= obj.month <= 12 else str(obj.month) def get_total_paid(self, obj): """Get total amount paid for this pay slip""" total = obj.payment_transactions.filter( status='COMPLETED' ).aggregate(total=models.Sum('amount'))['total'] return float(total) if total else 0 class MonthlyPaySlipDetailSerializer(MonthlyPaySlipSerializer): """Detailed Monthly Pay Slip Serializer with payment transactions""" payment_transactions = serializers.SerializerMethodField() remaining_balance = serializers.SerializerMethodField() class Meta(MonthlyPaySlipSerializer.Meta): fields = MonthlyPaySlipSerializer.Meta.fields + [ 'pay_structure_snapshot', 'payment_transactions', 'remaining_balance', ] def get_payment_transactions(self, obj): """Get all payment transactions for this pay slip""" # Remove is_active filter - PaymentTransaction doesn't have this field transactions = obj.payment_transactions.all() # Changed from filter(is_active=True) return PaymentTransactionListSerializer(transactions, many=True).data def get_remaining_balance(self, obj): """Calculate remaining balance to be paid""" total_paid = obj.payment_transactions.filter( status='COMPLETED' ).aggregate(total=models.Sum('amount'))['total'] or 0 remaining = float(obj.net_pay) - float(total_paid) return max(remaining, 0) # ===================================================== # PAYMENT TRANSACTION SERIALIZERS # ===================================================== class PaymentTransactionSerializer(serializers.ModelSerializer): """Complete Payment Transaction Serializer""" pay_slip_number = serializers.CharField(source='pay_slip.pay_slip_number', read_only=True) teacher_name = serializers.CharField(source='teacher.full_name', read_only=True) teacher_employee_id = serializers.CharField(source='teacher.employee_id', read_only=True) recorded_by_name = serializers.CharField(source='recorded_by.full_name', read_only=True, default=None) payment_method_display = serializers.CharField(source='get_payment_method_display', read_only=True) payment_type_display = serializers.CharField(source='get_payment_type_display', read_only=True) status_display = serializers.CharField(source='get_status_display', read_only=True) class Meta: model = PaymentTransaction fields = [ 'id', 'pay_slip', 'pay_slip_number', 'teacher', 'teacher_name', 'teacher_employee_id', 'payment_type', 'payment_type_display', 'amount', 'payment_method', 'payment_method_display', 'payment_date', 'transaction_id', 'bank_reference', 'cheque_number', 'upi_id', 'bank_name', 'bank_account_number', 'bank_ifsc_code', 'status', 'status_display', 'remarks', 'recorded_by', 'recorded_by_name', 'created_at', 'updated_at', ] read_only_fields = ['created_at', 'updated_at'] def validate_amount(self, value): """Validate amount is positive""" if value <= 0: raise serializers.ValidationError("Amount must be greater than zero") return value def validate(self, data): """Validate payment doesn't exceed pay slip balance""" pay_slip = data.get('pay_slip') amount = data.get('amount') if pay_slip and amount: total_paid = PaymentTransaction.objects.filter( pay_slip=pay_slip, status='COMPLETED' ).exclude(id=self.instance.id if self.instance else None).aggregate( total=models.Sum('amount') )['total'] or 0 remaining = float(pay_slip.net_pay) - float(total_paid) if float(amount) > remaining: raise serializers.ValidationError( f"Amount exceeds remaining balance. Remaining: {remaining}" ) return data class PaymentTransactionListSerializer(serializers.ModelSerializer): """List view Payment Transaction Serializer""" pay_slip_number = serializers.CharField(source='pay_slip.pay_slip_number', read_only=True) payment_method_display = serializers.CharField(source='get_payment_method_display', read_only=True) payment_type_display = serializers.CharField(source='get_payment_type_display', read_only=True) class Meta: model = PaymentTransaction fields = [ 'id', 'pay_slip', 'pay_slip_number', 'payment_type', 'payment_type_display', 'amount', 'payment_method', 'payment_method_display', 'payment_date', 'transaction_id', 'status', 'created_at', ] # ===================================================== # PAY SLIP TEMPLATE SERIALIZERS # ===================================================== class PaySlipTemplateSerializer(serializers.ModelSerializer): """Complete Pay Slip Template Serializer""" created_by_name = serializers.CharField(source='created_by.full_name', read_only=True, default=None) applicable_teachers_count = serializers.SerializerMethodField() applicable_teachers_list = serializers.SerializerMethodField() class Meta: model = PaySlipTemplate fields = [ 'id', 'name', 'description', 'applicable_teachers', 'applicable_teachers_count', 'applicable_teachers_list', 'designation', 'base_salary', 'dearness_allowance', 'house_rent_allowance', 'city_compensatory_allowance', 'travel_allowance', 'medical_allowance', 'special_allowance', 'education_allowance', 'telephone_allowance', 'provident_fund_percentage', 'esi_percentage', 'professional_tax_fixed', 'is_active', 'created_by', 'created_by_name', 'created_at', 'updated_at', ] read_only_fields = ['created_at', 'updated_at'] def get_applicable_teachers_count(self, obj): """Get count of teachers this template applies to""" return obj.applicable_teachers.filter(is_active=True).count() def get_applicable_teachers_list(self, obj): """Get list of applicable teachers""" teachers = obj.applicable_teachers.filter(is_active=True)[:10] return [{'id': t.id, 'name': t.full_name, 'employee_id': t.employee_id} for t in teachers] class PaySlipTemplateListSerializer(serializers.ModelSerializer): """List view Pay Slip Template Serializer""" applicable_teachers_count = serializers.SerializerMethodField() class Meta: model = PaySlipTemplate fields = [ 'id', 'name', 'description', 'designation', 'base_salary', 'applicable_teachers_count', 'is_active', 'created_at', ] def get_applicable_teachers_count(self, obj): """Get count of teachers this template applies to""" return obj.applicable_teachers.filter(is_active=True).count() # ===================================================== # REQUEST/ACTION SERIALIZERS # ===================================================== class GeneratePaySlipSerializer(serializers.Serializer): """Serializer for generating a single pay slip""" teacher_id = serializers.IntegerField() month = serializers.IntegerField(min_value=1, max_value=12) year = serializers.IntegerField(min_value=2000, max_value=2100) def validate(self, data): """Check if pay slip already exists""" teacher_id = data['teacher_id'] month = data['month'] year = data['year'] existing = MonthlyPaySlip.objects.filter( teacher_id=teacher_id, month=month, year=year, is_active=True ).first() if existing: raise serializers.ValidationError( f"Pay slip already exists for {month}/{year}" ) # Check if teacher has pay structure pay_structure = TeacherPayStructure.objects.filter( teacher_id=teacher_id, is_active=True ).first() if not pay_structure: raise serializers.ValidationError( "Teacher does not have an active pay structure" ) return data class BulkPaySlipGenerateSerializer(serializers.Serializer): """Serializer for generating multiple pay slips""" teacher_ids = serializers.ListField( child=serializers.IntegerField(), min_length=1 ) month = serializers.IntegerField(min_value=1, max_value=12) year = serializers.IntegerField(min_value=2000, max_value=2100) class PaySlipUpdateSerializer(serializers.Serializer): """Serializer for updating pay slip components""" performance_incentive = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) special_class_incentive = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) subject_expert_incentive = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) leadership_allowance = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) festival_bonus = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) annual_bonus = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) overtime_allowance = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) variable_pay = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) additional_earnings = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) other_allowances = serializers.JSONField(required=False, allow_null=True) loan_deduction = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) advance_deduction = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) attendance_deduction = serializers.DecimalField(max_digits=12, decimal_places=2, required=False, allow_null=True) other_deductions = serializers.JSONField(required=False, allow_null=True) casual_leave_taken = serializers.DecimalField(max_digits=5, decimal_places=1, required=False, allow_null=True) sick_leave_taken = serializers.DecimalField(max_digits=5, decimal_places=1, required=False, allow_null=True) earned_leave_taken = serializers.DecimalField(max_digits=5, decimal_places=1, required=False, allow_null=True) unpaid_leave_days = serializers.DecimalField(max_digits=5, decimal_places=1, required=False, allow_null=True) total_working_days = serializers.IntegerField(required=False, allow_null=True) days_present = serializers.IntegerField(required=False, allow_null=True) days_absent = serializers.IntegerField(required=False, allow_null=True) late_days = serializers.IntegerField(required=False, allow_null=True) remarks = serializers.CharField(required=False, allow_blank=True) class PaySlipApprovalSerializer(serializers.Serializer): """Serializer for pay slip approval""" approved = serializers.BooleanField() remarks = serializers.CharField(required=False, allow_blank=True) class PaySlipSummarySerializer(serializers.Serializer): """Serializer for pay slip summary statistics""" total_pay_slips = serializers.IntegerField() total_draft = serializers.IntegerField() total_pending = serializers.IntegerField() total_approved = serializers.IntegerField() total_paid = serializers.IntegerField() total_cancelled = serializers.IntegerField() total_net_pay = serializers.DecimalField(max_digits=15, decimal_places=2, allow_null=True) average_net_pay = serializers.DecimalField(max_digits=15, decimal_places=2, allow_null=True) class TeacherPaySummarySerializer(serializers.Serializer): """Serializer for teacher pay summary""" teacher_id = serializers.IntegerField() year = serializers.IntegerField() total_earned = serializers.DecimalField(max_digits=15, decimal_places=2) monthly_data = serializers.ListField() # ===================================================== # IMPORT FOR MODELS (to avoid circular imports) # ===================================================== # Add these to your existing serializers.py class PaymentTransactionSerializer(serializers.ModelSerializer): """Complete Payment Transaction Serializer""" pay_slip_number = serializers.CharField(source='pay_slip.pay_slip_number', read_only=True) teacher_name = serializers.CharField(source='teacher.full_name', read_only=True) teacher_employee_id = serializers.CharField(source='teacher.employee_id', read_only=True) recorded_by_name = serializers.CharField(source='recorded_by.full_name', read_only=True, default=None) payment_method_display = serializers.CharField(source='get_payment_method_display', read_only=True) payment_type_display = serializers.CharField(source='get_payment_type_display', read_only=True) status_display = serializers.CharField(source='get_status_display', read_only=True) class Meta: model = PaymentTransaction fields = [ 'id', 'pay_slip', 'pay_slip_number', 'teacher', 'teacher_name', 'teacher_employee_id', 'payment_type', 'payment_type_display', 'amount', 'payment_method', 'payment_method_display', 'payment_date', 'transaction_id', 'bank_reference', 'cheque_number', 'upi_id', 'bank_name', 'bank_account_number', 'bank_ifsc_code', 'status', 'status_display', 'remarks', 'recorded_by', 'recorded_by_name', 'created_at', 'updated_at', ] read_only_fields = ['created_at', 'updated_at'] def validate_amount(self, value): if value <= 0: raise serializers.ValidationError("Amount must be greater than zero") return value def validate(self, data): pay_slip = data.get('pay_slip') amount = data.get('amount') if pay_slip and amount: total_paid = PaymentTransaction.objects.filter( pay_slip=pay_slip, status='COMPLETED' ).exclude(id=self.instance.id if self.instance else None).aggregate( total=models.Sum('amount') )['total'] or 0 remaining = float(pay_slip.net_pay) - float(total_paid) if float(amount) > remaining: raise serializers.ValidationError( f"Amount exceeds remaining balance. Remaining: {remaining}" ) return data class PaymentTransactionListSerializer(serializers.ModelSerializer): """List view Payment Transaction Serializer""" pay_slip_number = serializers.CharField(source='pay_slip.pay_slip_number', read_only=True) teacher_name = serializers.CharField(source='teacher.full_name', read_only=True) payment_method_display = serializers.CharField(source='get_payment_method_display', read_only=True) payment_type_display = serializers.CharField(source='get_payment_type_display', read_only=True) status_display = serializers.CharField(source='get_status_display', read_only=True) class Meta: model = PaymentTransaction fields = [ 'id', 'pay_slip', 'pay_slip_number', 'teacher', 'teacher_name', 'payment_type', 'payment_type_display', 'amount', 'payment_method', 'payment_method_display', 'payment_date', 'transaction_id', 'status', 'status_display', 'created_at', ] class RecordPaymentSerializer(serializers.Serializer): """Serializer for recording a payment""" pay_slip_id = serializers.IntegerField() amount = serializers.DecimalField(max_digits=12, decimal_places=2) payment_method = serializers.CharField(max_length=20) payment_type = serializers.CharField(max_length=20, required=False, default='FULL') transaction_id = serializers.CharField(required=False, allow_blank=True, allow_null=True) bank_reference = serializers.CharField(required=False, allow_blank=True, allow_null=True) cheque_number = serializers.CharField(required=False, allow_blank=True, allow_null=True) upi_id = serializers.CharField(required=False, allow_blank=True, allow_null=True) bank_name = serializers.CharField(required=False, allow_blank=True, allow_null=True) bank_account_number = serializers.CharField(required=False, allow_blank=True, allow_null=True) bank_ifsc_code = serializers.CharField(required=False, allow_blank=True, allow_null=True) remarks = serializers.CharField(required=False, allow_blank=True, allow_null=True) def validate_amount(self, value): if value <= 0: raise serializers.ValidationError("Amount must be greater than zero") return value def validate(self, data): from .models import MonthlyPaySlip, PaymentTransaction pay_slip_id = data.get('pay_slip_id') amount = data.get('amount') try: pay_slip = MonthlyPaySlip.objects.get(id=pay_slip_id) except MonthlyPaySlip.DoesNotExist: raise serializers.ValidationError({"pay_slip_id": "Pay slip not found"}) if pay_slip.status != 'APPROVED': raise serializers.ValidationError( f"Pay slip must be approved before payment. Current status: {pay_slip.status}" ) total_paid = PaymentTransaction.objects.filter( pay_slip=pay_slip, status='COMPLETED' ).aggregate(total=models.Sum('amount'))['total'] or 0 remaining = float(pay_slip.net_pay) - float(total_paid) if float(amount) > remaining: raise serializers.ValidationError( f"Amount exceeds remaining balance. Remaining: {remaining}" ) data['pay_slip'] = pay_slip data['remaining_balance'] = remaining return data # Add these to your existing serializers.py class PaySlipTemplateSerializer(serializers.ModelSerializer): """Complete Pay Slip Template Serializer""" created_by_name = serializers.CharField(source='created_by.full_name', read_only=True, default=None) applicable_teachers_count = serializers.SerializerMethodField() applicable_teachers_list = serializers.SerializerMethodField() total_monthly_earnings = serializers.SerializerMethodField() class Meta: model = PaySlipTemplate fields = [ 'id', 'name', 'description', 'applicable_teachers', 'applicable_teachers_count', 'applicable_teachers_list', 'designation', 'base_salary', 'dearness_allowance', 'house_rent_allowance', 'city_compensatory_allowance', 'travel_allowance', 'medical_allowance', 'special_allowance', 'education_allowance', 'telephone_allowance', 'provident_fund_percentage', 'esi_percentage', 'professional_tax_fixed', 'total_monthly_earnings', 'is_active', 'created_by', 'created_by_name', 'created_at', 'updated_at', ] read_only_fields = ['created_at', 'updated_at'] def get_applicable_teachers_count(self, obj): """Get count of teachers this template applies to""" return obj.applicable_teachers.filter(is_active=True).count() def get_applicable_teachers_list(self, obj): """Get list of applicable teachers""" teachers = obj.applicable_teachers.filter(is_active=True)[:10] return [{'id': t.id, 'name': t.full_name, 'employee_id': t.employee_id} for t in teachers] def get_total_monthly_earnings(self, obj): """Calculate total monthly earnings from template""" total = float(obj.base_salary or 0) total += float(obj.dearness_allowance or 0) total += float(obj.house_rent_allowance or 0) total += float(obj.city_compensatory_allowance or 0) total += float(obj.travel_allowance or 0) total += float(obj.medical_allowance or 0) total += float(obj.special_allowance or 0) total += float(obj.education_allowance or 0) total += float(obj.telephone_allowance or 0) return round(total, 2) class PaySlipTemplateListSerializer(serializers.ModelSerializer): """List view Pay Slip Template Serializer""" applicable_teachers_count = serializers.SerializerMethodField() total_monthly_earnings = serializers.SerializerMethodField() class Meta: model = PaySlipTemplate fields = [ 'id', 'name', 'description', 'designation', 'base_salary', 'total_monthly_earnings', 'applicable_teachers_count', 'is_active', 'created_at', ] def get_applicable_teachers_count(self, obj): """Get count of teachers this template applies to""" return obj.applicable_teachers.filter(is_active=True).count() def get_total_monthly_earnings(self, obj): """Calculate total monthly earnings from template""" total = float(obj.base_salary or 0) total += float(obj.dearness_allowance or 0) total += float(obj.house_rent_allowance or 0) total += float(obj.city_compensatory_allowance or 0) total += float(obj.travel_allowance or 0) total += float(obj.medical_allowance or 0) total += float(obj.special_allowance or 0) total += float(obj.education_allowance or 0) total += float(obj.telephone_allowance or 0) return round(total, 2)