<?php
declare(strict_types=1);

require_once __DIR__ . '/../includes/bootstrap.php';

dbnToolsRequireMethod('GET');
dbnToolsRequireAuth();

try {
    $bnlDb = dbnToolsDb();
    $ragDb = dbnToolsRagDb();

    // Total documents in the do-better-legal corpus (corpus_id=1)
    $stmt = $ragDb->prepare('SELECT COUNT(*) FROM documents WHERE corpus_id = 1');
    $stmt->execute();
    $totalDocs = (int)$stmt->fetchColumn();

    // Total chunks for corpus_id=1 documents
    $stmt = $ragDb->prepare(
        'SELECT COUNT(*) FROM chunks c
         JOIN documents d ON c.document_id = d.id
         WHERE d.corpus_id = 1'
    );
    $stmt->execute();
    $totalChunks = (int)$stmt->fetchColumn();

    // Doc counts by category
    $stmt = $ragDb->prepare(
        'SELECT category, COUNT(*) AS doc_count
         FROM documents
         WHERE corpus_id = 1 AND category IS NOT NULL AND category != \'\'
         GROUP BY category
         ORDER BY doc_count DESC'
    );
    $stmt->execute();
    $byCategory = $stmt->fetchAll(PDO::FETCH_ASSOC);

    // Last updated timestamp
    $stmt = $ragDb->prepare('SELECT MAX(updated_at) FROM documents WHERE corpus_id = 1');
    $stmt->execute();
    $lastUpdated = $stmt->fetchColumn() ?: null;

    // Active sources from bnl_admin
    $stmt = $bnlDb->prepare(
        'SELECT name, url, category, authority_type, language, schedule, is_active, scraper_class
         FROM corpus_sources
         WHERE corpus_id = 1
         ORDER BY category, name'
    );
    $stmt->execute();
    $sources = $stmt->fetchAll(PDO::FETCH_ASSOC);

    $activeSources = count(array_filter($sources, fn($s) => !empty($s['is_active'])));

    dbnToolsRespond([
        'ok'    => true,
        'stats' => [
            'total_chunks'   => $totalChunks,
            'total_docs'     => $totalDocs,
            'active_sources' => $activeSources,
            'last_updated'   => $lastUpdated,
            'by_category'    => $byCategory,
        ],
        'sources' => $sources,
    ]);
} catch (Throwable $e) {
    dbnToolsError('Could not load corpus statistics: ' . $e->getMessage(), 500, 'corpus_stats_error');
}