"""
Forms for the notifications app.
"""

from django import forms
from django.utils.translation import gettext_lazy as _
from django.core.exceptions import ValidationError

from .models import MessageTemplate, Message, NotificationPreference


class MessageTemplateForm(forms.ModelForm):
    """Form for creating/editing message templates."""
    
    class Meta:
        model = MessageTemplate
        fields = [
            'code', 'name', 'channel', 'subject',
            'body_en', 'body_ar', 'variables', 'is_active'
        ]
        widgets = {
            'code': forms.TextInput(attrs={
                'class': 'form-control',
                'placeholder': _('e.g., appointment_reminder')
            }),
            'name': forms.TextInput(attrs={
                'class': 'form-control',
                'placeholder': _('Template Name')
            }),
            'channel': forms.Select(attrs={
                'class': 'form-select'
            }),
            'subject': forms.TextInput(attrs={
                'class': 'form-control',
                'placeholder': _('Email subject (optional)')
            }),
            'body_en': forms.Textarea(attrs={
                'class': 'form-control',
                'rows': 6,
                'placeholder': _('Message body in English. Use {variable_name} for variables.')
            }),
            'body_ar': forms.Textarea(attrs={
                'class': 'form-control',
                'rows': 6,
                'placeholder': _('Message body in Arabic (optional)')
            }),
            'variables': forms.Textarea(attrs={
                'class': 'form-control',
                'rows': 3,
                'placeholder': _('["patient_name", "appointment_date", "clinic_name"]')
            }),
            'is_active': forms.CheckboxInput(attrs={
                'class': 'form-check-input'
            }),
        }
    
    def clean_variables(self):
        """Validate and parse variables JSON."""
        import json
        variables = self.cleaned_data.get('variables')
        
        if isinstance(variables, str):
            try:
                variables = json.loads(variables)
            except json.JSONDecodeError:
                raise ValidationError(_('Invalid JSON format for variables'))
        
        if not isinstance(variables, list):
            raise ValidationError(_('Variables must be a list'))
        
        return variables
    
    def clean_code(self):
        """Ensure code is unique."""
        code = self.cleaned_data.get('code')
        
        # Check if code already exists (excluding current instance)
        qs = MessageTemplate.objects.filter(code=code)
        if self.instance.pk:
            qs = qs.exclude(pk=self.instance.pk)
        
        if qs.exists():
            raise ValidationError(_('A template with this code already exists'))
        
        return code


class MessageFilterForm(forms.Form):
    """Form for filtering messages."""
    
    search = forms.CharField(
        required=False,
        widget=forms.TextInput(attrs={
            'class': 'form-control',
            'placeholder': _('Search by recipient or content...')
        })
    )
    
    channel = forms.ChoiceField(
        required=False,
        choices=[('', _('All Channels'))] + list(Message.Channel.choices),
        widget=forms.Select(attrs={
            'class': 'form-select'
        })
    )
    
    status = forms.ChoiceField(
        required=False,
        choices=[('', _('All Statuses'))] + list(Message.Status.choices),
        widget=forms.Select(attrs={
            'class': 'form-select'
        })
    )
    
    date_from = forms.DateField(
        required=False,
        widget=forms.DateInput(attrs={
            'class': 'form-control',
            'type': 'date'
        })
    )
    
    date_to = forms.DateField(
        required=False,
        widget=forms.DateInput(attrs={
            'class': 'form-control',
            'type': 'date'
        })
    )
    
    template = forms.ModelChoiceField(
        queryset=MessageTemplate.objects.none(),
        required=False,
        widget=forms.Select(attrs={
            'class': 'form-select'
        }),
        empty_label=_('All Templates')
    )
    
    def __init__(self, *args, tenant=None, **kwargs):
        super().__init__(*args, **kwargs)
        if tenant:
            self.fields['template'].queryset = MessageTemplate.objects.filter(
                tenant=tenant
            ).order_by('name')


class BulkMessageForm(forms.Form):
    """Form for sending bulk messages."""
    
    channel = forms.ChoiceField(
        label=_('Channel'),
        choices=Message.Channel.choices,
        widget=forms.Select(attrs={
            'class': 'form-select'
        })
    )
    
    use_template = forms.BooleanField(
        label=_('Use Template'),
        required=False,
        initial=True,
        widget=forms.CheckboxInput(attrs={
            'class': 'form-check-input',
            'id': 'useTemplateCheckbox'
        })
    )
    
    template = forms.ModelChoiceField(
        label=_('Template'),
        queryset=MessageTemplate.objects.none(),
        required=False,
        widget=forms.Select(attrs={
            'class': 'form-select select2',
            'id': 'templateSelect'
        })
    )
    
    subject = forms.CharField(
        label=_('Subject'),
        required=False,
        widget=forms.TextInput(attrs={
            'class': 'form-control',
            'placeholder': _('Email subject (for email channel only)')
        })
    )
    
    message = forms.CharField(
        label=_('Message'),
        required=False,
        widget=forms.Textarea(attrs={
            'class': 'form-control',
            'rows': 6,
            'placeholder': _('Enter your message here...')
        })
    )
    
    recipient_filter = forms.ChoiceField(
        label=_('Recipients'),
        choices=[
            ('all', _('All Patients')),
            ('tags', _('By Tags')),
            ('custom', _('Custom List')),
        ],
        widget=forms.RadioSelect(attrs={
            'class': 'form-check-input'
        })
    )
    
    tags = forms.CharField(
        label=_('Patient Tags'),
        required=False,
        widget=forms.TextInput(attrs={
            'class': 'form-control',
            'placeholder': _('Enter tags separated by commas')
        })
    )
    
    recipients = forms.CharField(
        label=_('Recipients'),
        required=False,
        widget=forms.Textarea(attrs={
            'class': 'form-control',
            'rows': 4,
            'placeholder': _('Enter phone numbers or emails, one per line')
        })
    )
    
    def __init__(self, *args, tenant=None, **kwargs):
        super().__init__(*args, **kwargs)
        if tenant:
            self.fields['template'].queryset = MessageTemplate.objects.filter(
                tenant=tenant,
                is_active=True
            ).order_by('name')
    
    def clean(self):
        cleaned_data = super().clean()
        use_template = cleaned_data.get('use_template')
        template = cleaned_data.get('template')
        message = cleaned_data.get('message')
        recipient_filter = cleaned_data.get('recipient_filter')
        tags = cleaned_data.get('tags')
        recipients = cleaned_data.get('recipients')
        
        # Validate message content
        if use_template and not template:
            raise ValidationError(_('Please select a template'))
        
        if not use_template and not message:
            raise ValidationError(_('Please enter a message'))
        
        # Validate recipients
        if recipient_filter == 'tags' and not tags:
            raise ValidationError(_('Please enter at least one tag'))
        
        if recipient_filter == 'custom' and not recipients:
            raise ValidationError(_('Please enter at least one recipient'))
        
        return cleaned_data


class TestTemplateForm(forms.Form):
    """Form for testing message templates."""
    
    template = forms.ModelChoiceField(
        label=_('Template'),
        queryset=MessageTemplate.objects.none(),
        widget=forms.Select(attrs={
            'class': 'form-select select2'
        })
    )
    
    test_recipient = forms.CharField(
        label=_('Test Recipient'),
        widget=forms.TextInput(attrs={
            'class': 'form-control',
            'placeholder': _('Phone number or email')
        })
    )
    
    language = forms.ChoiceField(
        label=_('Language'),
        choices=[('en', _('English')), ('ar', _('Arabic'))],
        widget=forms.Select(attrs={
            'class': 'form-select'
        })
    )
    
    variables = forms.CharField(
        label=_('Variables (JSON)'),
        required=False,
        widget=forms.Textarea(attrs={
            'class': 'form-control',
            'rows': 4,
            'placeholder': _('{"patient_name": "Ahmed", "appointment_date": "2025-10-15"}')
        })
    )
    
    def __init__(self, *args, tenant=None, **kwargs):
        super().__init__(*args, **kwargs)
        if tenant:
            self.fields['template'].queryset = MessageTemplate.objects.filter(
                tenant=tenant,
                is_active=True
            ).order_by('name')
    
    def clean_variables(self):
        """Validate and parse variables JSON."""
        import json
        variables = self.cleaned_data.get('variables')
        
        if not variables:
            return {}
        
        try:
            variables = json.loads(variables)
        except json.JSONDecodeError:
            raise ValidationError(_('Invalid JSON format'))
        
        if not isinstance(variables, dict):
            raise ValidationError(_('Variables must be a JSON object'))
        
        return variables


class MessageRetryForm(forms.Form):
    """Form for retrying failed messages."""
    
    message_ids = forms.CharField(
        widget=forms.HiddenInput()
    )
    
    def clean_message_ids(self):
        """Parse and validate message IDs."""
        import json
        message_ids = self.cleaned_data.get('message_ids')
        
        try:
            message_ids = json.loads(message_ids)
        except json.JSONDecodeError:
            raise ValidationError(_('Invalid message IDs'))
        
        if not isinstance(message_ids, list):
            raise ValidationError(_('Message IDs must be a list'))
        
        return message_ids