File size: 6,370 Bytes
9a1014e
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
from __future__ import annotations

import os
import numpy as np
from dotenv import load_dotenv
from langchain_community.vectorstores import Chroma

from hf_text_embeddings import HFTextEmbeddings


DOCUMENT_PERSIST_DIR = "./chroma_db_docs"
DOCUMENT_COLLECTION = "document_context"

load_dotenv()


def _metadata_as_text(metadata: dict) -> str:
    searchable_fields = (
        "document_title",
        "document_type",
        "document_class",
        "keywords",
        "filename",
    )
    return " | ".join(
        str(metadata[field]).strip()
        for field in searchable_fields
        if metadata.get(field)
    )


def _combine_filters(first: dict | None, second: dict) -> dict:
    if not first:
        return second
    return {"$and": [first, second]}


def _classify_document_filter(
    vectorstore: Chroma,
    embeddings: HFTextEmbeddings,
    query: str,
    base_filter: dict | None = None,
) -> tuple[dict | None, dict | None, float | None]:
    get_kwargs = {"include": ["metadatas"]}
    if base_filter:
        get_kwargs["where"] = base_filter
    stored = vectorstore.get(**get_kwargs)

    candidates: dict[str, dict] = {}
    for metadata in stored.get("metadatas") or []:
        if not metadata:
            continue
        source = str(metadata.get("source") or "")
        if source and _metadata_as_text(metadata):
            candidates.setdefault(source, metadata)

    if not candidates:
        return base_filter, None, None

    sources = list(candidates)
    metadata_texts = [_metadata_as_text(candidates[source]) for source in sources]
    query_vector = np.asarray(embeddings.embed_query(query), dtype=np.float32)
    metadata_vectors = np.asarray(
        embeddings.embed_documents(metadata_texts),
        dtype=np.float32,
    )
    query_norm = np.linalg.norm(query_vector)
    metadata_norms = np.linalg.norm(metadata_vectors, axis=1)
    denominators = metadata_norms * query_norm
    scores = np.divide(
        metadata_vectors @ query_vector,
        denominators,
        out=np.zeros(len(metadata_vectors), dtype=np.float32),
        where=denominators != 0,
    )
    best_index = int(np.argmax(scores))
    best_source = sources[best_index]
    best_metadata = candidates[best_source]
    return (
        _combine_filters(base_filter, {"source": {"$eq": best_source}}),
        best_metadata,
        float(scores[best_index]),
    )


def retrieve_document_context(
    query: str,
    k: int = 4,
    filter_metadata: dict | None = None,
) -> str:
    try:
        embeddings = HFTextEmbeddings()
        vectorstore = Chroma(
            collection_name=os.getenv("DOCUMENT_CHROMA_COLLECTION", DOCUMENT_COLLECTION),
            embedding_function=embeddings,
            persist_directory=os.getenv("DOCUMENT_CHROMA_DIR", DOCUMENT_PERSIST_DIR),
        )
        selected_filter, selected_metadata, metadata_score = _classify_document_filter(
            vectorstore,
            embeddings,
            query,
            filter_metadata,
        )
        if selected_metadata is not None:
            print(
                "Metadata classifier | "
                f"score={metadata_score:.4f} | "
                f"document={selected_metadata.get('document_title')} | "
                f"type={selected_metadata.get('document_type')}",
                flush=True,
            )

        # Evita el query HNSW de Chroma, que puede bloquearse en algunos
        # contenedores. La coleccion ASTM es pequena, por lo que un ranking
        # coseno directo sobre los embeddings persistidos es rapido y estable.
        get_kwargs = {"include": ["documents", "metadatas", "embeddings"]}
        if selected_filter:
            get_kwargs["where"] = selected_filter
        stored = vectorstore.get(**get_kwargs)
        documents = stored.get("documents") or []
        metadatas = stored.get("metadatas") or []
        stored_embeddings = stored.get("embeddings")
        if not documents or stored_embeddings is None:
            print("Document Chroma returned no searchable chunks.", flush=True)
            return ""

        query_vector = np.asarray(embeddings.embed_query(query), dtype=np.float32)
        chunk_vectors = np.asarray(stored_embeddings, dtype=np.float32)
        query_norm = np.linalg.norm(query_vector)
        chunk_norms = np.linalg.norm(chunk_vectors, axis=1)
        denominators = chunk_norms * query_norm
        similarities = np.divide(
            chunk_vectors @ query_vector,
            denominators,
            out=np.zeros(len(chunk_vectors), dtype=np.float32),
            where=denominators != 0,
        )
        top_indices = np.argsort(similarities)[::-1][: min(k, len(documents))]
        blocks = []
        for rank, index in enumerate(top_indices, start=1):
            metadata = metadatas[index] if index < len(metadatas) else {}
            print(
                f"Document rank {rank} | similarity={similarities[index]:.4f} | "
                f"document={metadata.get('document_title')}",
                flush=True,
            )
            blocks.append(
                f"[Documento {rank}] metadata={metadata}\n{documents[index]}"
            )
        return "\n\n".join(blocks)
    except Exception as exc:
        print(f"Document Chroma retrieval skipped: {exc}", flush=True)
        return ""


def build_context_prompt(
    user_text: str,
    k: int = 4,
    conversation_history: str = "",
) -> str:
    document_context = retrieve_document_context(user_text, k=k)

    context_parts = []
    if document_context:
        context_parts.append("Contexto normativo/documental recuperado de documentos/Chroma:\n" + document_context)

    if not context_parts:
        return user_text

    context = "\n\n".join(context_parts)
    return f"""Sos el agente del proyecto Alberti/Metalurgia.
Usa como fuente principal el contexto técnico y normativo recuperado desde los documentos indexados en Chroma.
Cuando respondas sobre datos del proyecto, prioriza los registros recuperados y menciona información relacionada si ayudan pero no divulgues ID o datos propios de los registros.
Si el contexto recuperado no alcanza para responder con precision, dilo claramente y no inventes datos exactos.

{context}

Historial reciente de esta conversacion:
{conversation_history or "Sin mensajes anteriores."}

Pregunta del usuario:
{user_text}"""