from django import forms
from django.db.models.query import QuerySet
from django.http import HttpRequest, HttpResponse
from django.contrib import admin, messages
from django.utils.translation import ngettext
from django.utils.safestring import SafeText

import nested_admin

from durationwidget.widgets import TimeDurationWidget 

from import_export import fields
from import_export.admin import ImportMixin
from import_export.resources import ModelResource
from import_export.widgets import CharWidget

from django_admin_action_forms import AdminActionFormsMixin, AdminActionForm, action_with_form

from .models.courses import Course
from .models.hourbuildings import HourBuilding, HourBuildingLeg
from .models.missions import Training, MissionProfile
from .models.students import Student
from .models.weekpref import WeekPreference

from .custom.colortag import course_color
from .actions.exportweek import export_selected

from datetime import date

class TrainingForm(forms.ModelForm):
    model=Training
    
class HourBuildingLegForm(forms.ModelForm):
    class Meta:
        model = HourBuildingLeg
        fields = '__all__'
        widgets = {
            'time': TimeDurationWidget(show_days=False, 
                                       show_seconds=False
            )
        }

# Register your models here.
class HourBuildingLegInline(nested_admin.NestedTabularInline):
    model = HourBuildingLeg
    form = HourBuildingLegForm
    extra = 0
    fk_name = 'hb'
    max_num = 5

    # If user is a student deny edit permission for week past the current one
    def has_change_permission(self, request: HttpRequest, obj: HourBuilding | None = None):
        if hasattr(request.user, 'student') and obj:
            current_week = date.today().isocalendar().week
            if not obj.DoesNotExist and current_week > obj.weekpref.week:
                return False
        return True
    
    def has_delete_permission(self, request: HttpRequest, obj: HourBuilding | None = None):
        return self.has_change_permission(request=request, obj=obj)

class HourBuildingInLine(nested_admin.NestedTabularInline):
    model = HourBuilding
    extra = 0
    inlines = [HourBuildingLegInline]
    fk_name = 'weekpref'
    verbose_name_plural = "Hour Building"
    max_num = 7

    # If user is a student deny edit permission for week past the current one
    def has_change_permission(self, request: HttpRequest, obj: WeekPreference | None = None):
        if hasattr(request.user, 'student') and obj:
            current_week = date.today().isocalendar().week
            if current_week > obj.week:
                return False
        return True
    
    def has_delete_permission(self, request: HttpRequest, obj: WeekPreference | None = None):
        return self.has_change_permission(request=request, obj=obj)

class TrainingInLIne(nested_admin.NestedTabularInline):
    model = Training
    form = TrainingForm
    extra = 0
    fk_name = 'weekpref'
    verbose_name_plural = "Training Missions"
    max_num = 7

    # If user is a student deny edit permission for week past the current one
    def has_change_permission(self, request: HttpRequest, obj: WeekPreference | None = None):
        if hasattr(request.user, 'student') and obj:
            current_week = date.today().isocalendar().week
            if current_week > obj.week:
                return False
        return True
    
    def has_delete_permission(self, request: HttpRequest, obj: WeekPreference | None = None):
        return self.has_change_permission(request=request, obj=obj)
    
class WeekPreferenceAdmin(nested_admin.NestedModelAdmin):
    inlines = (TrainingInLIne, HourBuildingInLine,)
    list_display = ("week", "student__surname","student__name", "student__course", "course_color", "student_brief_mix",)
    list_filter = ("week", "student__course", "student",)
    actions = ("export",)

    @admin.action(description="Export Selected Preferences")
    def export(weekpreferenceadmin, request: HttpRequest, queryset: QuerySet[WeekPreference]) -> HttpResponse | None:
        if queryset.count() == 0:
            return None
        weekpreferenceadmin.message_user(request, ngettext("Exporting %d row", "Exporting %d rows", queryset.count()) % queryset.count(), messages.SUCCESS)
        return export_selected(request=request, queryset=queryset)       
        
    @admin.display(description="Mission Count")
    def student_brief_mix(self, obj: WeekPreference) -> SafeText:
        if not obj.student.course:
            return SafeText("")
        return SafeText(f"{Training.objects.filter(weekpref = obj.id).count()}")

    @admin.display(description="Color")
    def course_color(self, obj: WeekPreference) -> SafeText:
        if not obj.student.course:
            return SafeText("")
        return course_color(obj.student.course.color)
    
    # If a user is registered as student hide filters
    def get_list_filter(self, request):
        list_filter = super().get_list_filter(request)
        if hasattr(request.user, 'student'):
            return []
        return list_filter
    
    # If a user is registered as student do not show actions
    def get_actions(self, request):
        actions = super().get_actions(request)
        if hasattr(request.user, 'student'):
            return []
        return actions

    # If a user is registered as student show only their preferences
    def get_queryset(self, request):
        qs = super().get_queryset(request)
        if hasattr(request.user, 'student'):
            return qs.filter(student=request.user.student)
        # If admin show everything
        return qs

    def get_form(self, request, obj=None, **kwargs):
        form: forms.Form = super().get_form(request, obj, **kwargs)
        current_week = date.today().isocalendar().week

        # If form contains the week field
        if 'week' in form.base_fields:
            # Set default value as current week
            form.base_fields['week'].initial = current_week

        # If student is current user making request
        if hasattr(request.user, 'student'):
            student = request.user.student
            if 'student' in form.base_fields:
                form.base_fields['student'].initial = student
                form.base_fields['student'].disabled = True
                form.base_fields['week'].disabled = True # student cannot change week 
        return form
    
    # If user is a student deny edit permission for week past the current one
    def has_change_permission(self, request, obj: WeekPreference | None = None):
        if hasattr(request.user, 'student') and obj:
            current_week = date.today().isocalendar().week
            if current_week > obj.week:
                return False
        return True
    
    # If user is a student deny edit permission for week past the current one
    def has_add_permission(self, request, obj: WeekPreference | None = None):
        if hasattr(request.user, 'student') and obj:
            current_week = date.today().isocalendar().week
            if current_week > obj.week:
                return False
        return True
    
    # If user is a student deny edit permission for week past the current one
    def has_delete_permission(self, request, obj: WeekPreference | None = None):
        if hasattr(request.user, 'student') and obj:
            current_week = date.today().isocalendar().week
            if current_week > obj.week:
                return False
        return True
    
    def changeform_view(self, request: HttpRequest, object_id: int | None = None, form_url: str = '', extra_context=None):
        extra_context = extra_context or {}
        if hasattr(request.user, 'student') and object_id:
            current_week = date.today().isocalendar().week
            weekpref = WeekPreference.objects.get(id=object_id)
            if current_week > weekpref.week:
                extra_context['show_save'] = False
                extra_context['show_save_and_continue'] = False
                extra_context['show_save_and_add_another'] = False
                extra_context['show_delete'] = False
        return super().changeform_view(request, object_id, form_url, extra_context)
    
    def save_model(self, request, obj, form, change):
        # Imposta automaticamente lo studente se non è già valorizzato
        if hasattr(request.user, 'student') and not obj.student_id:
            obj.student = request.user.student
        super().save_model(request, obj, form, change)


# Resource Class for Student data import
class StudentResource(ModelResource):
    surname = fields.Field(attribute="surname", column_name="surname", widget=CharWidget())
    name = fields.Field(attribute="name", column_name="name", widget=CharWidget())
    email = fields.Field(attribute="email", column_name="email", widget=CharWidget())
    phone = fields.Field(attribute="phone", column_name="phone", widget=CharWidget())

    # Cleanup fields before entering
    def before_import_row(self, row: dict[str, str], **kwargs) -> None:
        row['name'] = SafeText(row['name'].capitalize().strip())
        row['surname'] = SafeText(row['surname'].capitalize().strip())
        row['phone'] = SafeText(row['phone'].replace(' ',''))
        row['email'] = SafeText(row['email'].lower().strip())
        return super().before_import_row(row, **kwargs)

    class Meta:
        model = Student
        skip_unchanged = True
        report_skipped = True
        fields = ('surname', 'name', 'email', 'phone')
        import_id_fields = ['email', 'phone']

# Form Class for Student course change
class ChangeCourseForm(AdminActionForm):
    course = forms.ModelChoiceField(queryset=Course.objects.all())

class StudentAdmin(ImportMixin, AdminActionFormsMixin,  admin.ModelAdmin):
    list_display = ("surname", "name", "course", "course_color", "email", "phone", "password", "active")
    list_filter = ("course", "active")
    actions = ("change_course", "disable_students")
    resource_classes = [StudentResource]

    @admin.display(description="Color")
    def course_color(self, obj: Student) -> SafeText:
        if not obj.course:
            return SafeText("")
        return course_color(obj.course.color)

    @admin.display(description="Password")
    def password(self, obj: Student) -> SafeText:
        return SafeText(obj.default_password())
    
    @admin.action(description="Disable Students")
    def disable_students(self, request: HttpRequest, queryset: QuerySet[Student]):
        for q in queryset.all():
            if q.user:
                q.user.is_staff = False
                q.user.save()
        count: int = queryset.update(active = False)
        messages.success(request, f"{count} students deactivated")
        pass

    @action_with_form(ChangeCourseForm, description="Change Student Course")
    def change_course(self, request: HttpRequest, queryset: QuerySet[Student], data):
        course = data["course"]
        count: int = queryset.update(course=course)
        messages.success(request, f"{count} students updated to {course}")
        
class CourseAdmin(admin.ModelAdmin):
    list_display = ("ctype", "cnumber","color_display", "year")
    list_filter = ("ctype", "year")
    
    # Dinamically add color_display property to show a colored dot
    @admin.display(description="Color")
    def color_display(self, obj: Course) -> SafeText:
        if not obj.pk:
            return SafeText("")
        return course_color(obj.color)

class MissionProfileAdmin(admin.ModelAdmin):
    list_display = ("mtype", "mnum",)
    list_filter = ("mtype",)

admin.site.register(Course, CourseAdmin)
admin.site.register(MissionProfile, MissionProfileAdmin)
admin.site.register(Student, StudentAdmin)
admin.site.register(WeekPreference, WeekPreferenceAdmin)