"""Context fact and document CRUD — MIT licensed."""
from __future__ import annotations

import sqlite3
import uuid
from dataclasses import dataclass
from datetime import datetime, timezone
from pathlib import Path


@dataclass(frozen=True)
class ContextFact:
    id: str
    category: str
    key: str
    value: str
    source: str | None
    created_at: str


@dataclass(frozen=True)
class ContextDocument:
    id: str
    filename: str
    doc_type: str
    full_text: str
    file_size: int | None
    uploaded_at: str


def _connect(db_path: Path) -> sqlite3.Connection:
    conn = sqlite3.connect(str(db_path))
    conn.execute("PRAGMA journal_mode=WAL")
    conn.execute("PRAGMA foreign_keys=ON")
    conn.row_factory = sqlite3.Row
    return conn


def add_fact(db_path: Path, category: str, key: str, value: str, source: str | None = None) -> ContextFact:
    fact = ContextFact(
        id=str(uuid.uuid4()),
        category=category,
        key=key,
        value=value,
        source=source,
        created_at=datetime.now(timezone.utc).isoformat(),
    )
    conn = _connect(db_path)
    conn.execute(
        "INSERT INTO context_facts(id, category, key, value, source, created_at) VALUES (?,?,?,?,?,?)",
        (fact.id, fact.category, fact.key, fact.value, fact.source, fact.created_at),
    )
    conn.commit()
    conn.close()
    return fact


def list_facts(db_path: Path, category: str | None = None) -> list[ContextFact]:
    conn = _connect(db_path)
    if category:
        rows = conn.execute(
            "SELECT * FROM context_facts WHERE category=? ORDER BY created_at", (category,)
        ).fetchall()
    else:
        rows = conn.execute(
            "SELECT * FROM context_facts ORDER BY category, created_at"
        ).fetchall()
    conn.close()
    return [
        ContextFact(
            id=r["id"], category=r["category"], key=r["key"],
            value=r["value"], source=r["source"], created_at=r["created_at"],
        )
        for r in rows
    ]


def delete_fact(db_path: Path, fact_id: str) -> bool:
    conn = _connect(db_path)
    cursor = conn.execute("DELETE FROM context_facts WHERE id=?", (fact_id,))
    conn.commit()
    conn.close()
    return cursor.rowcount > 0


def add_document(
    db_path: Path,
    filename: str,
    doc_type: str,
    full_text: str,
    file_size: int | None = None,
) -> ContextDocument:
    doc = ContextDocument(
        id=str(uuid.uuid4()),
        filename=filename,
        doc_type=doc_type,
        full_text=full_text,
        file_size=file_size,
        uploaded_at=datetime.now(timezone.utc).isoformat(),
    )
    conn = _connect(db_path)
    conn.execute(
        "INSERT INTO context_documents(id, filename, doc_type, full_text, file_size, uploaded_at)"
        " VALUES (?,?,?,?,?,?)",
        (doc.id, doc.filename, doc.doc_type, doc.full_text, doc.file_size, doc.uploaded_at),
    )
    conn.commit()
    conn.close()
    return doc


def list_documents(db_path: Path) -> list[ContextDocument]:
    conn = _connect(db_path)
    rows = conn.execute(
        "SELECT id, filename, doc_type, full_text, file_size, uploaded_at"
        " FROM context_documents ORDER BY uploaded_at DESC"
    ).fetchall()
    conn.close()
    return [
        ContextDocument(
            id=r["id"], filename=r["filename"], doc_type=r["doc_type"],
            full_text=r["full_text"], file_size=r["file_size"], uploaded_at=r["uploaded_at"],
        )
        for r in rows
    ]


def delete_document(db_path: Path, doc_id: str) -> bool:
    conn = _connect(db_path)
    cursor = conn.execute("DELETE FROM context_documents WHERE id=?", (doc_id,))
    conn.commit()
    conn.close()
    return cursor.rowcount > 0