"""Recipe import: photo/screenshot (AI vision), pasted text (AI) and links.

Every path ends in the normal recipe form, pre-filled as an editable draft and posted to
recipes:create. Nothing is saved before the user presses "Speichern".
"""

from django import forms
from django.contrib import messages
from django.shortcuts import redirect, render
from django.urls import reverse
from django.views.decorators.http import require_POST

from . import ai, images
from .forms import MultipleFileInput, MultipleImageField, RecipeForm


class PhotoImportForm(forms.Form):
    photos = MultipleImageField(
        label="Foto oder Screenshot",
        widget=MultipleFileInput(attrs={"accept": "image/*"}),
        help_text=f"Bis zu {ai.MAX_IMAGES} Bilder vom selben Rezept, z. B. Kochbuchseite oder Screenshot.",
    )

    def clean_photos(self):
        photos = self.cleaned_data["photos"]
        if not photos:
            raise forms.ValidationError("Bitte wähle ein Bild aus.")
        if len(photos) > ai.MAX_IMAGES:
            raise forms.ValidationError(f"Höchstens {ai.MAX_IMAGES} Bilder.")
        return photos


class TextImportForm(forms.Form):
    text = forms.CharField(
        label="Rezepttext",
        max_length=ai.MAX_INPUT_CHARS,
        widget=forms.Textarea(attrs={"rows": 8, "placeholder": "Rezept hier einfügen, z. B. die Beschreibung eines Instagram-Beitrags"}),
    )
    source_url = forms.URLField(label="Quelle (optional)", required=False, max_length=1000, assume_scheme="https")


def render_draft(request, initial, notice, ai_draft=None, extra_context=None):
    """Show the recipe form filled with a draft; it posts to recipes:create."""
    form = RecipeForm(initial=initial)
    return render(request, "recipes/form.html", {
        "form": form, "is_new": True, "draft_notice": notice, "ai_draft": ai_draft,
        "form_action": reverse("recipes:create"), **(extra_context or {}),
    })


def import_start(request, photo_form=None, text_form=None):
    return render(request, "recipes/import.html", {
        "photo_form": photo_form or PhotoImportForm(),
        "text_form": text_form or TextImportForm(),
    })


@require_POST
def import_photo(request):
    form = PhotoImportForm(request.POST, request.FILES)
    if not form.is_valid():
        return import_start(request, photo_form=form)
    try:
        jpegs = [images.prepare_for_ai(f) for f in form.cleaned_data["photos"]]
        draft = ai.extract_from_images(request.user, jpegs)
    except (ai.AIError, images.ImageError) as error:
        messages.error(request, getattr(error, "user_message", str(error)))
        return redirect("recipes:import")
    return render_draft(request, draft.to_form_initial(), "Aus dem Bild erkannt", ai_draft=draft)


@require_POST
def import_text(request):
    form = TextImportForm(request.POST)
    if not form.is_valid():
        return import_start(request, text_form=form)
    try:
        draft = ai.structure_text(request.user, form.cleaned_data["text"])
    except ai.AIError as error:
        messages.error(request, error.user_message)
        return import_start(request, text_form=form)
    initial = {**draft.to_form_initial(), "source_url": form.cleaned_data["source_url"]}
    return render_draft(request, initial, "Aus dem Text erkannt", ai_draft=draft)