from django import forms
from .models import PotholeDetection

ALLOWED_IMAGE_EXTENSIONS = ['jpg', 'jpeg', 'png', 'webp']
MAX_IMAGE_SIZE_MB = 20


class PotholeDetectionForm(forms.ModelForm):
    uploaded_image = forms.ImageField(
        label='Image de voirie',
        help_text=f"Formats acceptés : {', '.join(ALLOWED_IMAGE_EXTENSIONS).upper()} — taille max {MAX_IMAGE_SIZE_MB} MB",
    )
    confidence_threshold = forms.FloatField(
        label='Seuil de confiance',
        min_value=0.1,
        max_value=0.9,
        initial=0.25,
        widget=forms.NumberInput(attrs={'step': '0.05', 'class': 'form-control'}),
        help_text='Valeur entre 0.1 et 0.9 (défaut : 0.25)',
    )
    notes = forms.CharField(
        label='Notes',
        required=False,
        widget=forms.Textarea(attrs={'rows': 3, 'class': 'form-control'}),
    )

    class Meta:
        model = PotholeDetection
        fields = ['uploaded_image', 'confidence_threshold', 'notes']

    def clean_uploaded_image(self):
        image = self.cleaned_data.get('uploaded_image')
        if image:
            ext = image.name.rsplit('.', 1)[-1].lower()
            if ext not in ALLOWED_IMAGE_EXTENSIONS:
                raise forms.ValidationError(
                    f"Format non supporté : {ext}. Formats acceptés : {', '.join(ALLOWED_IMAGE_EXTENSIONS)}."
                )
            if image.size > MAX_IMAGE_SIZE_MB * 1024 * 1024:
                raise forms.ValidationError(
                    f"L'image est trop volumineuse ({image.size / 1024 / 1024:.1f} MB). Taille max : {MAX_IMAGE_SIZE_MB} MB."
                )
        return image