import json
import base64
import jsonschema
import pandas as pd

from nacl.exceptions import CryptoError
from django import forms
from django.core.cache import cache
from django.utils.translation import gettext_lazy as _
from django.core.exceptions import ValidationError
from utils import certs
from idhub.models import (
    DID,
    File_datas,
    Membership,
    Schemas,
    UserRol,
    VerificableCredential,
)
from idhub_auth.models import User


class TermsConditionsForm2(forms.Form):
    accept = forms.BooleanField(
        label=_("Accept terms and conditions of the service"),
        required=False
    )

    def __init__(self, *args, **kwargs):
        self.user = kwargs.pop('user', None)
        super().__init__(*args, **kwargs)

    def clean(self):
        data = self.cleaned_data
        if data.get("accept"):
            self.user.accept_gdpr = True
        else:
            self.user.accept_gdpr = False        
        return data
        
    def save(self, commit=True):

        if commit:
            self.user.save()
            return self.user
        
        return 


class EncryptionKeyForm(forms.Form):
    key = forms.CharField(
        label=_("Key for encrypt the secrets of all system"),
        required=True
    )

    def clean(self):
        data = self.cleaned_data
        self._key = data["key"]
        if not DID.objects.exists():
            return data

        did = DID.objects.first()
        cache.set("KEY_DIDS", self._key, None)
        try:
            did.get_key_material()
        except CryptoError:
            cache.set("KEY_DIDS", None)
            txt = _("Key no valid!")
            raise ValidationError(txt)

        cache.set("KEY_DIDS", None)
        return data

    def save(self, commit=True):

        if commit:
            cache.set("KEY_DIDS", self._key, None)
            if not DID.objects.exists():
                did = DID.objects.create(label='Default', type=DID.Types.WEB)
                did.set_did()
                did.save()
        
        return 


class TermsConditionsForm(forms.Form):
    accept_privacy = forms.BooleanField(
        widget=forms.CheckboxInput(attrs={'class': 'form-check-input'}),
        required=False
    )
    accept_legal = forms.BooleanField(
        widget=forms.CheckboxInput(attrs={'class': 'form-check-input'}),
        required=False
    )
    accept_cookies = forms.BooleanField(
        widget=forms.CheckboxInput(attrs={'class': 'form-check-input'}),
        required=False
    )

    def __init__(self, *args, **kwargs):
        self.user = kwargs.pop('user', None)
        super().__init__(*args, **kwargs)

    def get_label(self, url, read):
        label = _('I read and accepted the')
        label += f' <a class="btn btn-green-admin" target="_blank" href="{url}" '
        label += f'title="{read}">{read}</a>'
        return label

    def privacy_label(self):
        url = "https://laweb.pangea.org/politica-de-privacitat/"
        read = _("Privacy policy")
        return self.get_label(url, read)

    def legal_label(self):
        url = "https://laweb.pangea.org/avis-legal/"
        read = _("Legal policy")
        return self.get_label(url, read)

    def cookies_label(self):
        url = "https://laweb.pangea.org/politica-de-cookies-2/"
        read = _("Cookies policy")
        return self.get_label(url, read)

    def clean(self):
        data = self.cleaned_data
        privacy = data.get("accept_privacy")
        legal = data.get("accept_legal")
        cookies = data.get("accept_cookies")
        if privacy and legal and cookies:
            self.user.accept_gdpr = True
        else:
            self.user.accept_gdpr = False        
        return data
        
    def save(self, commit=True):

        if commit:
            self.user.save()
            return self.user
        
        return 


class ImportForm(forms.Form):
    did = forms.ChoiceField(label=_("Did"), choices=[])
    eidas1 = forms.ChoiceField(
        label=_("Signature with Eidas1"),
        choices=[],
        required=False
    )
    schema = forms.ChoiceField(label=_("Schema"), choices=[])
    file_import = forms.FileField(label=_("File import"))

    def __init__(self, *args, **kwargs):
        self._schema = None
        self._did = None
        self._eidas1 = None
        self.rows = {}
        self.properties = {}
        self.users = []
        super().__init__(*args, **kwargs)
        dids = DID.objects.filter(user__isnull=True)
        self.fields['did'].choices = [
            (x.did, x.label) for x in dids.filter(eidas1=False)
        ]
        self.fields['schema'].choices = [(0, _('Select one'))] + [
            (x.id, x.name) for x in Schemas.objects.filter()
        ]
        if dids.filter(eidas1=True).exists():
            choices = [("", "")]
            choices.extend([
                (x.did, x.label) for x in dids.filter(eidas1=True)
            ])
            self.fields['eidas1'].choices = choices
        else:
          self.fields.pop('eidas1')

    def clean(self):
        data = self.cleaned_data["did"]
        did = DID.objects.filter(
            user__isnull=True,
            did=data
        )

        if not did.exists():
            raise ValidationError("Did is not valid!")

        self._did = did.first()

        eidas1 = self.cleaned_data.get('eidas1')
        if eidas1:
            self._eidas1 = DID.objects.filter(
                user__isnull=True,
                eidas1=True,
                did=eidas1
            ).first()
            
        return data

    def clean_schema(self):
        data = self.cleaned_data["schema"]
        schema = Schemas.objects.filter(
            id=data
        )
        if not schema.exists():
            raise ValidationError("Schema is not valid!")

        self._schema = schema.first()
        try:
            self.json_schema = self._schema.get_credential_subject_schema()
        except Exception:
            raise ValidationError("Schema is not valid!")

        return data

    def clean_file_import(self):
        data = self.cleaned_data["file_import"]
        self.file_name = data.name

        if not self._schema:
            return data

        df = pd.read_excel(data)
        # convert dates to iso 8601
        for col in df.select_dtypes(include='datetime').columns:
            df[col] = df[col].dt.strftime("%Y-%m-%d")

        for col in df.select_dtypes(include=['number']).columns:
            sc_col = self.json_schema.get("properties", {}).get(col, {})
            if sc_col.get("type") == "string":
                df[col] = df[col].astype(str)

        data_pd = df.fillna('').to_dict()

        if not data_pd or df.last_valid_index() is None:
            self.exception("The file you try to import is empty!")

        for n in range(df.last_valid_index()+1):
            row = {}
            for k in data_pd.keys():
                if data_pd[k][n] or data_pd[k][n] == 0:
                    row[k] = data_pd[k][n]

            user = self.validate_jsonld(n, row)
            self.rows[user] = row

        return data

    def save(self, commit=True):
        table = []
        for k, v in self.rows.items():
            table.append(self.create_credential(k, v)) 

        if commit:
            for cred in table:
              cred.save()
            File_datas.objects.create(file_name=self.file_name)
            return table
        
        return 

    def validate_jsonld(self, line, row):
        try:
            jsonschema.validate(
                instance=row,
                schema=self.json_schema,
                format_checker=jsonschema.Draft202012Validator.FORMAT_CHECKER
            )
        except jsonschema.exceptions.ValidationError as err:
            msg = "line {}: {}".format(line+1, err)
            return self.exception(msg)

        user, new = User.objects.get_or_create(email=row.get('email'))
        if new:
            self.users.append(user)
            user.set_encrypted_sensitive_data()
            user.save()
            self.create_defaults_dids(user)

        return user

    def create_defaults_dids(self, user):
        did = DID(label="Default", user=user, type=DID.Types.WEB)
        did.set_did()
        did.save()

    def create_credential(self, user, row):
        bcred = VerificableCredential.objects.filter(
            user=user,
            schema=self._schema,
            issuer_did=self._did,
            status=VerificableCredential.Status.ENABLED
        )
        if bcred.exists():
            cred = bcred.first()
            cred.csv_data = json.dumps(row, default=str)
            cred.eidas1_did = self._eidas1
            return cred

        cred = VerificableCredential(
            verified=False,
            user=user,
            csv_data=json.dumps(row, default=str),
            issuer_did=self._did,
            schema=self._schema,
            eidas1_did=self._eidas1
        )
        cred.set_type()
        return cred

    def exception(self, msg):
        File_datas.objects.create(file_name=self.file_name, success=False)
        raise ValidationError(msg)


class SchemaForm(forms.Form):
    file_template = forms.FileField(label=_("File template"))

    
class MembershipForm(forms.ModelForm):

    class Meta:
        model = Membership
        fields = ['type', 'start_date', 'end_date']

    def clean_end_date(self):
        data = super().clean()
        start_date = data['start_date']
        end_date = data.get('end_date')
        members = Membership.objects.filter(
            type=data['type'],
            user=self.instance.user
        )
        if self.instance.id:
            members = members.exclude(id=self.instance.id)

        if members.filter(start_date__lte=start_date, end_date=None).exists():
            msg = _("This membership already exists!")
            raise forms.ValidationError(msg)
            
        if (start_date and end_date):
            if start_date > end_date:
                msg = _("The end date is less than the start date")
                raise forms.ValidationError(msg)

            members = members.filter(
                start_date__lte=end_date,
                end_date__gte=start_date,
            )

            if members.exists():
                msg = _("This membership already exists!")
                raise forms.ValidationError(msg)

        if not end_date:
            members = members.filter(
                start_date__gte=start_date,
            )

            if members.exists():
                msg = _("This membership already exists!")
                raise forms.ValidationError(msg)
            
        
        return end_date


class UserRolForm(forms.ModelForm):

    class Meta:
        model = UserRol
        fields = ['service']

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        if not self.instance.id:
            user = self.instance.user
            choices = self.fields['service'].choices
            choices.queryset = choices.queryset.exclude(users__user=user)
            self.fields['service'].choices = choices
    
    def clean_service(self):
        data = super().clean()
        service = UserRol.objects.filter(
            service=data['service'],
            user=self.instance.user
        )

        if service.exists():
            msg = _("Is not possible to have a duplicate role")
            raise forms.ValidationError(msg)

        return data['service']


class ImportCertificateForm(forms.Form):
    label = forms.CharField(label=_("Label"))
    password = forms.CharField(
        label=_("Password of certificate"),
        widget=forms.PasswordInput
    )
    file_import = forms.FileField(label=_("File import"))

    def __init__(self, *args, **kwargs):
        self._did = None
        self._s = None
        self._label = None
        super().__init__(*args, **kwargs)

    def clean(self):
        data = super().clean()
        file_import = data.get('file_import')
        self.pfx_file = file_import.read()
        self.file_name = file_import.name
        self._pss = data.get('password')
        self._label = data.get('label')
        if not self.pfx_file or not self._pss:
            msg = _("Is not a valid certificate")
            raise forms.ValidationError(msg)

        self.signer_init()
        if not self._s:
            msg = _("Is not a valid certificate")
            raise forms.ValidationError(msg)

        self.new_did()
        return data

    def new_did(self):
        keys = {
            "cert": base64.b64encode(self.pfx_file).decode('utf-8'),
            "passphrase": self._pss
        }
        key_material = json.dumps(keys)
        self._did = DID(
            key_material=key_material,
            did=self.file_name,
            label=self._label,
            eidas1=True,
            type=DID.Types.KEY
        )

        self._did.set_key_material(key_material)

    def save(self, commit=True):

        if commit:
            self._did.save()
            return self._did

        return

    def signer_init(self):
        self._s = certs.load_cert(
            self.pfx_file, self._pss.encode('utf-8')
        )