src/validation/validator.py

import os
import re
from pathlib import Path
from rdflib import Graph, Literal, RDF, Namespace
from rdflib.namespace import SKOS
from pyshacl import validate

class SemanticValidator:
    def __init__(self, ontology_dir="./ontology", shapes_file="./ontology/shapes/auto_constraints.ttl"):
        self.shapes_file = shapes_file
        
        # Mappatura namespace
        self.namespaces = {
            "arco": Namespace("https://w3id.org/arco/ontology/arco/"),
            "core": Namespace("https://w3id.org/arco/ontology/core/"),
            "a-loc": Namespace("https://w3id.org/arco/ontology/location/"),
            "a-cd": Namespace("https://w3id.org/arco/ontology/context-description/"),
            "cis": Namespace("http://dati.beniculturali.it/cis/"),
            "crm": Namespace("http://www.cidoc-crm.org/cidoc-crm/"), 
            "ex": Namespace("http://activadigital.it/ontology/") 
        }
        
        print("🛡️  Inizializzazione Semantic Validator (OWL RL)...")
        
        # Caricamento massivo dell'Ontologia in memoria per il Reasoner
        self.ont_graph = Graph()
        
        arco_path = Path(ontology_dir) / "arco"
        if arco_path.exists():
            for owl_file in arco_path.glob("*.owl"):
                self.ont_graph.parse(str(owl_file), format="xml")
                
        cidoc_path = Path(ontology_dir) / "cidoc-crm" / "cidoc-crm.owl"
        if cidoc_path.exists():
            self.ont_graph.parse(str(cidoc_path), format="xml")
            
        print(f"✅ Ontologia completa caricata nel reasoner ({len(self.ont_graph)} triple).")

        if os.path.exists(self.shapes_file):
            self.shacl_graph = Graph()
            self.shacl_graph.parse(self.shapes_file, format="turtle")
            print("🛡️  SHACL Auto-Constraints caricati.")
        else:
            print("⚠️  File SHACL non trovato. Validazione disabilitata (pericoloso in prod!).")
            self.shacl_graph = None

    def _get_uri(self, text_val):
        if ":" in text_val and not text_val.startswith("http"):
            prefix, name = text_val.split(":", 1)
            if prefix in self.namespaces:
                return self.namespaces[prefix][name]
        
        clean_name = text_val.replace(" ", "_")
        clean_name = re.sub(r'[^a-zA-Z0-9_]', '', clean_name)
        
        if not clean_name:
            clean_name = "UnknownEntity"
            
        return self.namespaces["ex"][clean_name]

    def _json_to_rdf(self, entities, triples):
        g = Graph()
        for prefix, ns in self.namespaces.items():
            g.bind(prefix, ns)
        g.bind("skos", SKOS)

        if entities:
            for ent in entities:
                label = ent["label"] if isinstance(ent, dict) else str(ent)
                ent_uri = self._get_uri(label)
                g.add((ent_uri, SKOS.prefLabel, Literal(label, lang="it")))

        if triples:
            for t in triples:
                subj_uri = self._get_uri(t.subject)
                g.add((subj_uri, SKOS.prefLabel, Literal(t.subject, lang="it")))

                if t.predicate.lower() in ["rdf:type", "a", "type", "rdf_type"]:
                    obj_uri = self._get_uri(t.object)
                    g.add((subj_uri, RDF.type, obj_uri))
                else:
                    pred_uri = self._get_uri(t.predicate)
                    obj_uri = self._get_uri(t.object)
                    g.add((subj_uri, pred_uri, obj_uri))
                    g.add((obj_uri, SKOS.prefLabel, Literal(t.object, lang="it")))
        return g

    def filter_valid_triples(self, entities, triples):
        """
        Esegue la validazione bloccante (OWL RL).
        Ritorna le triple valide da salvare su Neo4j e quelle invalide da buttare su Mongo.
        """
        if not self.shacl_graph or not triples:
            return triples, [], "No Validation"

        # 1. Testiamo l'intero batch in un colpo solo per massima velocità
        batch_graph = self._json_to_rdf(entities, triples)
        conforms, report_graph, report_text = validate(
            batch_graph,
            shacl_graph=self.shacl_graph,
            ont_graph=self.ont_graph,
            inference='owlrl'
        )

        if conforms:
            return triples, [], "All valid"

        print("⚠️ Rilevate violazioni SHACL nel blocco. Isolamento colpevoli...")
        
        # 2. Se fallisce, isoliamo chirurgicamente le triple non conformi
        valid_triples = []
        invalid_triples = []

        for t in triples:
            single_graph = self._json_to_rdf(entities, [t])
            t_conforms, _, t_report = validate(
                single_graph,
                shacl_graph=self.shacl_graph,
                ont_graph=self.ont_graph,
                inference='owlrl'
            )
            if t_conforms:
                valid_triples.append(t)
            else:
                invalid_triples.append({
                    "triple": t.model_dump() if hasattr(t, 'model_dump') else t,
                    "violation_report": t_report
                })

        return valid_triples, invalid_triples, report_text