from django.shortcuts import render, redirect, get_object_or_404
from django.http.response import HttpResponseNotAllowed
from django.contrib.auth.decorators import permission_required, login_required
from django.http import HttpResponse, JsonResponse, HttpResponseForbidden, HttpResponseBadRequest, HttpResponseNotAllowed
from django.contrib.auth import logout
from django.urls import reverse
from django.views.generic.detail import SingleObjectMixin, DetailView
from django.contrib.auth.mixins import LoginRequiredMixin
from django.contrib import messages
from django.core.exceptions import ValidationError
from django.utils import timezone

import json

from .forms import FileUploadForm, UploadCertificateForm, RuleAttributeForm
from .models import File, Rule, UserAttribute, RuleAttribute, AttributeType, User

def create_user(request):
    special_user = request.user
    if special_user.has_perm('abac.can_create_users'):
        pass #TODO: Create new User
    else:
        # Return a response indicating insufficient permissions
        return HttpResponseNotAllowed(request)
    
@permission_required('abac.can_create_users', raise_exception=True)
def create_user_view(request):
    # Your view logic here
    return HttpResponse('New user created')

@login_required
def landing_page(request):
    files = File.objects.all()
    return render(request, 'landing_page.html', {'files': files})

def login_view(request):
    return HttpResponse('Login View')

def logout_view(request):
    logout(request)
    return redirect('abac:login')

@login_required
def upload_file_view(request):
    if request.method == 'POST':
        form = FileUploadForm(request.POST, request.FILES)
        if form.is_valid():
            file_instance = form.save(commit=False)
            file_instance.owner = request.user  # Assign the logged-in user as the owner of the uploaded file.
            file_instance.save()
            return redirect('abac:home')  # Redirect to the landing page after a successful file upload.
    else:
        form = FileUploadForm()
    return render(request, 'file_upload.html', {'form': form})

def create_user_view(request):
    return HttpResponse('Create User View')

@login_required
def upload_certificate_view(request):
    if request.method == 'POST':
        uploaded_file = request.FILES.get('certificate')

        if not uploaded_file:
            return HttpResponseBadRequest('No file uploaded.')

        certificate_data = json.load(uploaded_file)

        for attribute_data in certificate_data:
            name = attribute_data.get('name')
            value = attribute_data.get('value')

            # Assuming you have a method to get or create AttributeType
            attribute_type = get_or_create_attribute_type(name, value, private=True)

            attribute, created = UserAttribute.objects.update_or_create(
                user=request.user,
                attribute_type=attribute_type,
                defaults={'value': value, 'last_modified': timezone.now()}
            )

        messages.success(request, 'Certificate uploaded successfully.')
        return redirect('abac:user_details', username=request.user.username)
    else:
        form = UploadCertificateForm()

    return render(request, 'upload_certificate.html', {'form': form})

@login_required
def file_detail(request, file_id):
    file = get_object_or_404(File, id=file_id)
    rules = Rule.objects.filter(file=file)
    return render(request, 'file_detail.html', {'file': file, 'rules': rules})

@login_required
def create_rule(request, file_id):
    file = get_object_or_404(File, id=file_id)
    
    if request.method == "POST":
        rule_name = request.POST.get('rule_name')
        if rule_name:
            rule = Rule.objects.create(name=rule_name, file=file)
            url = reverse('abac:rule_detail', args=[file_id, rule.id])
            return redirect(url)
    
    # If the rule_name is not provided or if the method is GET, redirect to file_detail view.
    return redirect('abac:file_detail', file_id=file_id)


@login_required
def rule_detail(request, file_id, rule_id=None):
    file = get_object_or_404(File, id=file_id)
    rule = get_object_or_404(Rule, id=rule_id) if rule_id else None
    
    if request.method == "POST":
        form = RuleAttributeForm(request.POST)
        if form.is_valid():
            rule_attribute = form.save(commit=False)
            rule_attribute.rule = rule
            rule_attribute.save()
            return redirect('abac:rule_detail', file_id=file_id, rule_id=rule_id)
    else:
        form = RuleAttributeForm()
    
    rule_attributes = RuleAttribute.objects.filter(rule=rule) if rule else []
    
    return render(request, 'rule_detail.html', {
        'file': file,
        'rule': rule,
        'form': form,
        'rule_attributes': rule_attributes
    })

@login_required
def delete_rule_attribute(request, file_id, rule_id, rule_attribute_id):
    rule_attribute = get_object_or_404(RuleAttribute, id=rule_attribute_id)    
    rule_attribute.delete()
    return redirect('abac:rule_detail', file_id=file_id, rule_id=rule_id)
        
@login_required
def user_detail_view(request, username):
    user = get_object_or_404(User, username=username)

    # Check if the requested user is the same as the logged-in user or the logged-in user has the required permission
    if user != request.user and not request.user.has_perm('abac.can_create_users'):
        return HttpResponseForbidden('You do not have permission to view this page.')

    attributes = UserAttribute.objects.filter(user=user)
    return render(request, 'user_detail.html', {'user': user, 'attributes': attributes})




def get_or_create_attribute_type(name, value, private=False):
    # Determine the datatype from the value
    if isinstance(value, int):
        datatype = 'INTEGER'
    elif isinstance(value, float):
        datatype = 'FLOAT'
    elif isinstance(value, bool):
        datatype = 'BOOLEAN'
    elif isinstance(value, str):
        datatype = 'STRING'
    else:
        raise ValidationError('Invalid data type in certificate for attribute: {}'.format(name))
    
    # Try to get the existing AttributeType object with matching name and datatype.
    attribute_type, created = AttributeType.objects.get_or_create(
        name=name, 
        datatype=datatype
    )
    
    if not created and attribute_type.datatype != datatype:
        # If an AttributeType with the same name but different datatype exists, create a new one.
        attribute_type = AttributeType.objects.create(name=name, datatype=datatype, is_private=private)
        
    return attribute_type