"""
Django admin configuration for finance app.
"""

from django.contrib import admin
from django.utils.translation import gettext_lazy as _
from simple_history.admin import SimpleHistoryAdmin

from .models import (
    Service,
    Package,
    Payer,
    Invoice,
    InvoiceLineItem,
    Payment,
    PackagePurchase,
    CSID,
)


@admin.register(Service)
class ServiceAdmin(admin.ModelAdmin):
    """Admin interface for Service model."""
    
    list_display = ['code', 'name_en', 'clinic', 'base_price', 'duration_minutes', 'is_active', 'tenant']
    list_filter = ['clinic', 'is_active', 'tenant']
    search_fields = ['code', 'name_en', 'name_ar']
    readonly_fields = ['id', 'created_at', 'updated_at']
    
    fieldsets = (
        (None, {
            'fields': ('code', 'name_en', 'name_ar', 'clinic', 'tenant', 'is_active')
        }),
        (_('Pricing & Duration'), {
            'fields': ('base_price', 'duration_minutes')
        }),
        (_('Description'), {
            'fields': ('description',),
            'classes': ('collapse',)
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


@admin.register(Package)
class PackageAdmin(admin.ModelAdmin):
    """Admin interface for Package model."""
    
    list_display = ['name_en', 'total_sessions', 'price', 'validity_days', 'is_active', 'tenant']
    list_filter = ['is_active', 'tenant']
    search_fields = ['name_en', 'name_ar']
    readonly_fields = ['id', 'created_at', 'updated_at']
    filter_horizontal = ['services']
    
    fieldsets = (
        (None, {
            'fields': ('name_en', 'name_ar', 'tenant', 'is_active')
        }),
        (_('Package Details'), {
            'fields': ('services', 'total_sessions', 'price', 'validity_days')
        }),
        (_('Description'), {
            'fields': ('description',),
            'classes': ('collapse',)
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


@admin.register(Payer)
class PayerAdmin(admin.ModelAdmin):
    """Admin interface for Payer model."""
    
    list_display = ['name', 'patient', 'payer_type', 'coverage_percentage', 'is_active', 'tenant']
    list_filter = ['payer_type', 'is_active', 'tenant']
    search_fields = ['name', 'policy_number', 'patient__mrn', 'patient__first_name_en', 'patient__last_name_en']
    readonly_fields = ['id', 'created_at', 'updated_at']
    
    fieldsets = (
        (None, {
            'fields': ('patient', 'name', 'payer_type', 'tenant', 'is_active')
        }),
        (_('Coverage Details'), {
            'fields': ('policy_number', 'coverage_percentage')
        }),
        (_('Notes'), {
            'fields': ('notes',),
            'classes': ('collapse',)
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


class InvoiceLineItemInline(admin.TabularInline):
    """Inline admin for Invoice Line Items."""
    
    model = InvoiceLineItem
    extra = 1
    readonly_fields = ['id']
    fields = ['service', 'package', 'description', 'quantity', 'unit_price', 'total']


@admin.register(Invoice)
class InvoiceAdmin(SimpleHistoryAdmin):
    """Admin interface for Invoice model."""
    
    list_display = ['invoice_number', 'invoice_counter', 'patient', 'invoice_type', 'issue_date', 
                    'total', 'status', 'zatca_status', 'tenant']
    list_filter = ['status', 'invoice_type', 'zatca_status', 'tenant', 'issue_date', 'due_date']
    search_fields = ['invoice_number', 'patient__mrn', 'patient__first_name_en', 'patient__last_name_en']
    readonly_fields = ['id', 'invoice_number', 'invoice_counter', 'invoice_hash', 'previous_invoice_hash',
                       'qr_code', 'cryptographic_stamp', 'amount_paid', 'amount_due', 'is_fully_paid', 
                       'created_at', 'updated_at', 'zatca_submission_date', 'zatca_response']
    date_hierarchy = 'issue_date'
    inlines = [InvoiceLineItemInline]
    
    fieldsets = (
        (_('Identification'), {
            'fields': ('invoice_number', 'invoice_counter', 'invoice_type', 'tenant')
        }),
        (_('Core Information'), {
            'fields': ('patient', 'appointment', 'payer')
        }),
        (_('Credit/Debit Note Reference'), {
            'fields': ('billing_reference_id', 'billing_reference_issue_date'),
            'classes': ('collapse',)
        }),
        (_('Dates'), {
            'fields': ('issue_date', 'issue_time', 'due_date')
        }),
        (_('Amounts'), {
            'fields': ('subtotal', 'tax', 'discount', 'total', 'amount_paid', 'amount_due', 'is_fully_paid')
        }),
        (_('Status'), {
            'fields': ('status',)
        }),
        (_('ZATCA E-Invoice'), {
            'fields': ('invoice_hash', 'previous_invoice_hash', 'qr_code', 'cryptographic_stamp',
                      'zatca_status', 'zatca_submission_date', 'zatca_response', 'xml_content'),
            'classes': ('collapse',)
        }),
        (_('Notes'), {
            'fields': ('notes',),
            'classes': ('collapse',)
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


@admin.register(InvoiceLineItem)
class InvoiceLineItemAdmin(admin.ModelAdmin):
    """Admin interface for InvoiceLineItem model."""
    
    list_display = ['invoice', 'description', 'quantity', 'unit_price', 'total']
    list_filter = ['invoice__status', 'invoice__tenant']
    search_fields = ['invoice__invoice_number', 'description']
    readonly_fields = ['id']
    
    fieldsets = (
        (None, {
            'fields': ('invoice', 'service', 'package')
        }),
        (_('Details'), {
            'fields': ('description', 'quantity', 'unit_price', 'total')
        }),
        (_('Metadata'), {
            'fields': ('id',),
            'classes': ('collapse',)
        }),
    )


@admin.register(Payment)
class PaymentAdmin(admin.ModelAdmin):
    """Admin interface for Payment model."""
    
    list_display = ['invoice', 'payment_date', 'amount', 'method', 'status', 'processed_by', 'tenant']
    list_filter = ['method', 'status', 'tenant', 'payment_date']
    search_fields = ['invoice__invoice_number', 'transaction_id', 'reference']
    readonly_fields = ['id', 'created_at', 'updated_at']
    date_hierarchy = 'payment_date'
    
    fieldsets = (
        (None, {
            'fields': ('invoice', 'tenant', 'status')
        }),
        (_('Payment Details'), {
            'fields': ('payment_date', 'amount', 'method', 'processed_by')
        }),
        (_('Transaction Information'), {
            'fields': ('transaction_id', 'reference'),
            'classes': ('collapse',)
        }),
        (_('Notes'), {
            'fields': ('notes',),
            'classes': ('collapse',)
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


@admin.register(PackagePurchase)
class PackagePurchaseAdmin(admin.ModelAdmin):
    """Admin interface for PackagePurchase model."""
    
    list_display = ['patient', 'package', 'purchase_date', 'expiry_date', 'total_sessions', 
                    'sessions_used', 'sessions_remaining', 'status', 'tenant']
    list_filter = ['status', 'tenant', 'purchase_date', 'expiry_date']
    search_fields = ['patient__mrn', 'patient__first_name_en', 'patient__last_name_en', 
                     'package__name_en']
    readonly_fields = ['id', 'sessions_remaining', 'is_expired', 'is_completed', 'created_at', 'updated_at']
    date_hierarchy = 'purchase_date'
    
    fieldsets = (
        (None, {
            'fields': ('patient', 'package', 'tenant', 'status')
        }),
        (_('Purchase Details'), {
            'fields': ('invoice', 'purchase_date', 'expiry_date')
        }),
        (_('Session Tracking'), {
            'fields': ('total_sessions', 'sessions_used', 'sessions_remaining', 'is_expired', 'is_completed')
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


@admin.register(CSID)
class CSIDAdmin(admin.ModelAdmin):
    """Admin interface for CSID model."""
    
    list_display = ['common_name', 'csid_type', 'status', 'issue_date', 'expiry_date', 
                    'days_until_expiry', 'invoices_signed', 'tenant']
    list_filter = ['csid_type', 'status', 'tenant', 'issue_date', 'expiry_date']
    search_fields = ['common_name', 'egs_serial_number', 'organization_unit']
    readonly_fields = ['id', 'is_valid', 'days_until_expiry', 'needs_renewal', 
                       'invoices_signed', 'last_used', 'created_at', 'updated_at']
    date_hierarchy = 'issue_date'
    
    fieldsets = (
        (_('CSID Information'), {
            'fields': ('csid_type', 'status', 'tenant')
        }),
        (_('Certificate Details'), {
            'fields': ('certificate', 'secret', 'request_id')
        }),
        (_('EGS Unit Information'), {
            'fields': ('egs_serial_number', 'common_name', 'organization_unit')
        }),
        (_('Validity'), {
            'fields': ('issue_date', 'expiry_date', 'is_valid', 'days_until_expiry', 'needs_renewal')
        }),
        (_('Revocation'), {
            'fields': ('revocation_date', 'revocation_reason'),
            'classes': ('collapse',)
        }),
        (_('Usage Statistics'), {
            'fields': ('invoices_signed', 'last_used')
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )
    
    actions = ['revoke_selected_csids']
    
    def revoke_selected_csids(self, request, queryset):
        """Revoke selected CSIDs."""
        count = 0
        for csid in queryset.filter(status=CSID.Status.ACTIVE):
            csid.revoke(reason="Revoked via admin interface")
            count += 1
        
        self.message_user(request, f"Successfully revoked {count} CSID(s).")
    
    revoke_selected_csids.short_description = "Revoke selected CSIDs"