from pathlib import Path

from django import forms

from apps.scenarios.services import ScenarioNotFound, get_scenario

SUPPORTED_EXTENSIONS = {".txt", ".md", ".pdf", ".docx"}


class DocumentUploadForm(forms.Form):
    scenario_id = forms.CharField(label="场景")
    file = forms.FileField(label="文件")

    def clean_scenario_id(self):
        scenario_id = self.cleaned_data["scenario_id"]
        try:
            get_scenario(scenario_id)
        except ScenarioNotFound as exc:
            raise forms.ValidationError("场景不存在") from exc
        return scenario_id

    def clean_file(self):
        uploaded_file = self.cleaned_data["file"]
        extension = Path(uploaded_file.name).suffix.lower()
        if extension not in SUPPORTED_EXTENSIONS:
            raise forms.ValidationError("仅支持 .txt、.md、.pdf 和 .docx 文件")
        return uploaded_file