"""
Django admin configuration for appointments app.
"""

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

from .models import (
    Provider,
    Room,
    Schedule,
    Appointment,
    AppointmentReminder,
    AppointmentConfirmation,
    Session,
    SessionParticipant,
)


@admin.register(Provider)
class ProviderAdmin(admin.ModelAdmin):
    """Admin interface for Provider model."""
    
    list_display = ['user', 'is_available', 'max_daily_appointments', 'tenant', 'created_at']
    list_filter = ['is_available', 'tenant', 'created_at']
    search_fields = ['user__username', 'user__first_name', 'user__last_name', 'user__email']
    readonly_fields = ['id', 'created_at', 'updated_at']
    filter_horizontal = ['specialties']
    
    fieldsets = (
        (None, {
            'fields': ('user', 'tenant', 'is_available')
        }),
        (_('Configuration'), {
            'fields': ('specialties', 'max_daily_appointments')
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


@admin.register(Room)
class RoomAdmin(admin.ModelAdmin):
    """Admin interface for Room model."""
    
    list_display = ['room_number', 'name', 'clinic', 'is_available', 'tenant']
    list_filter = ['is_available', 'clinic', 'tenant']
    search_fields = ['name', 'room_number']
    readonly_fields = ['id', 'created_at', 'updated_at']
    
    fieldsets = (
        (None, {
            'fields': ('name', 'room_number', 'clinic', 'tenant', 'is_available')
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


@admin.register(Schedule)
class ScheduleAdmin(admin.ModelAdmin):
    """Admin interface for Schedule model."""
    
    list_display = ['provider', 'day_of_week', 'start_time', 'end_time', 'slot_duration', 'is_active']
    list_filter = ['day_of_week', 'is_active', 'provider']
    search_fields = ['provider__user__username', 'provider__user__first_name', 'provider__user__last_name']
    readonly_fields = ['id', 'created_at', 'updated_at']
    
    fieldsets = (
        (None, {
            'fields': ('provider', 'day_of_week', 'is_active')
        }),
        (_('Time Configuration'), {
            'fields': ('start_time', 'end_time', 'slot_duration')
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


@admin.register(Appointment)
class AppointmentAdmin(SimpleHistoryAdmin):
    """Admin interface for Appointment model."""
    
    list_display = ['appointment_number', 'patient', 'provider', 'scheduled_date', 'scheduled_time', 
                    'status', 'finance_cleared', 'consent_verified']
    list_filter = ['status', 'clinic', 'scheduled_date', 'finance_cleared', 'consent_verified', 'tenant']
    search_fields = ['appointment_number', 'patient__mrn', 'patient__first_name_en', 
                     'patient__last_name_en', 'provider__user__username']
    readonly_fields = ['id', 'appointment_number', 'created_at', 'updated_at', 'is_past']
    date_hierarchy = 'scheduled_date'
    
    fieldsets = (
        (_('Identification'), {
            'fields': ('appointment_number', 'tenant')
        }),
        (_('Core Information'), {
            'fields': ('patient', 'clinic', 'provider', 'room', 'service_type')
        }),
        (_('Scheduling'), {
            'fields': ('scheduled_date', 'scheduled_time', 'duration')
        }),
        (_('Status'), {
            'fields': ('status', 'finance_cleared', 'consent_verified')
        }),
        (_('Confirmation'), {
            'fields': ('confirmation_sent_at', 'confirmation_method'),
            'classes': ('collapse',)
        }),
        (_('Timestamps'), {
            'fields': ('arrival_at', 'start_at', 'end_at'),
            'classes': ('collapse',)
        }),
        (_('Rescheduling'), {
            'fields': ('reschedule_reason', 'reschedule_count'),
            'classes': ('collapse',)
        }),
        (_('Cancellation'), {
            'fields': ('cancel_reason', 'cancelled_by'),
            'classes': ('collapse',)
        }),
        (_('Additional Information'), {
            'fields': ('notes',),
            'classes': ('collapse',)
        }),
        (_('Metadata'), {
            'fields': ('id', 'is_past', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


@admin.register(AppointmentReminder)
class AppointmentReminderAdmin(admin.ModelAdmin):
    """Admin interface for AppointmentReminder model."""
    
    list_display = ['appointment', 'reminder_type', 'scheduled_for', 'status', 'sent_at']
    list_filter = ['reminder_type', 'status', 'scheduled_for']
    search_fields = ['appointment__appointment_number', 'appointment__patient__mrn']
    readonly_fields = ['id', 'created_at', 'updated_at']
    date_hierarchy = 'scheduled_for'
    
    fieldsets = (
        (None, {
            'fields': ('appointment', 'reminder_type', 'status')
        }),
        (_('Scheduling'), {
            'fields': ('scheduled_for', 'sent_at')
        }),
        (_('Message'), {
            'fields': ('message',),
            'classes': ('collapse',)
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


@admin.register(AppointmentConfirmation)
class AppointmentConfirmationAdmin(admin.ModelAdmin):
    """Admin interface for AppointmentConfirmation model."""
    
    list_display = ['appointment', 'status', 'confirmation_method', 'sent_at', 'confirmed_at', 
                    'expires_at', 'is_valid']
    list_filter = ['status', 'confirmation_method', 'sent_at', 'confirmed_at', 'expires_at']
    search_fields = ['appointment__appointment_number', 'appointment__patient__mrn', 'token']
    readonly_fields = ['id', 'token', 'is_expired', 'is_valid', 'created_at', 'updated_at']
    date_hierarchy = 'created_at'
    
    fieldsets = (
        (None, {
            'fields': ('appointment', 'token', 'status', 'confirmation_method')
        }),
        (_('Timing'), {
            'fields': ('sent_at', 'confirmed_at', 'expires_at', 'is_expired', 'is_valid')
        }),
        (_('Confirmation Details'), {
            'fields': ('confirmed_by_ip', 'confirmed_by_user_agent'),
            'classes': ('collapse',)
        }),
        (_('Reminders'), {
            'fields': ('reminder_count', 'last_reminder_at'),
            'classes': ('collapse',)
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )


class SessionParticipantInline(admin.TabularInline):
    """Inline admin for session participants."""
    model = SessionParticipant
    extra = 0
    readonly_fields = ['appointment_number', 'created_at']
    fields = ['patient', 'appointment_number', 'status', 'finance_cleared', 'consent_verified', 
              'arrival_at', 'attended_at']
    
    def has_add_permission(self, request, obj=None):
        """Allow adding participants through the inline."""
        return True


@admin.register(Session)
class SessionAdmin(SimpleHistoryAdmin):
    """Admin interface for Session model."""
    
    list_display = ['session_number', 'session_type', 'provider', 'clinic', 'scheduled_date', 
                    'scheduled_time', 'capacity_display', 'status', 'tenant']
    list_filter = ['session_type', 'status', 'clinic', 'scheduled_date', 'tenant']
    search_fields = ['session_number', 'provider__user__first_name', 'provider__user__last_name',
                     'service_type']
    readonly_fields = ['id', 'session_number', 'current_capacity', 'available_spots', 
                       'is_full', 'capacity_percentage', 'created_at', 'updated_at']
    date_hierarchy = 'scheduled_date'
    inlines = [SessionParticipantInline]
    
    fieldsets = (
        (_('Identification'), {
            'fields': ('session_number', 'tenant', 'session_type')
        }),
        (_('Core Information'), {
            'fields': ('provider', 'clinic', 'room', 'service_type')
        }),
        (_('Scheduling'), {
            'fields': ('scheduled_date', 'scheduled_time', 'duration')
        }),
        (_('Capacity'), {
            'fields': ('max_capacity', 'current_capacity', 'available_spots', 
                      'is_full', 'capacity_percentage')
        }),
        (_('Status'), {
            'fields': ('status', 'start_at', 'end_at')
        }),
        (_('Notes'), {
            'fields': ('group_notes',),
            'classes': ('collapse',)
        }),
        (_('Cancellation'), {
            'fields': ('cancel_reason', 'cancelled_by'),
            'classes': ('collapse',)
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )
    
    def capacity_display(self, obj):
        """Display capacity as current/max."""
        return f"{obj.current_capacity}/{obj.max_capacity}"
    capacity_display.short_description = _('Capacity')
    
    def get_queryset(self, request):
        """Optimize queryset with related objects."""
        qs = super().get_queryset(request)
        return qs.select_related('provider__user', 'clinic', 'room', 'tenant')


@admin.register(SessionParticipant)
class SessionParticipantAdmin(SimpleHistoryAdmin):
    """Admin interface for SessionParticipant model."""
    
    list_display = ['appointment_number', 'patient', 'session', 'status', 
                    'finance_cleared', 'consent_verified', 'arrival_at', 'attended_at']
    list_filter = ['status', 'finance_cleared', 'consent_verified', 'session__scheduled_date',
                   'session__clinic']
    search_fields = ['appointment_number', 'patient__mrn', 'patient__first_name_en', 
                     'patient__last_name_en', 'session__session_number']
    readonly_fields = ['id', 'appointment_number', 'can_check_in', 'created_at', 'updated_at']
    date_hierarchy = 'created_at'
    
    fieldsets = (
        (_('Identification'), {
            'fields': ('appointment_number', 'session', 'patient')
        }),
        (_('Status'), {
            'fields': ('status', 'can_check_in')
        }),
        (_('Prerequisites'), {
            'fields': ('finance_cleared', 'consent_verified')
        }),
        (_('Timestamps'), {
            'fields': ('confirmation_sent_at', 'arrival_at', 'attended_at'),
            'classes': ('collapse',)
        }),
        (_('Notes'), {
            'fields': ('individual_notes',),
            'classes': ('collapse',)
        }),
        (_('Cancellation'), {
            'fields': ('cancel_reason', 'cancelled_by'),
            'classes': ('collapse',)
        }),
        (_('No-Show'), {
            'fields': ('no_show_reason', 'no_show_notes'),
            'classes': ('collapse',)
        }),
        (_('Metadata'), {
            'fields': ('id', 'created_at', 'updated_at'),
            'classes': ('collapse',)
        }),
    )
    
    def get_queryset(self, request):
        """Optimize queryset with related objects."""
        qs = super().get_queryset(request)
        return qs.select_related('session__provider__user', 'session__clinic', 'patient')