import { Injectable } from '@nestjs/common';
import { SqliteService } from '../db/sqlite.service';
import * as fs from 'fs';
import * as path from 'path';
@Injectable()
export class DocsService {
private dbContentCache = new Map<string, any>();
constructor(private readonly sqlite: SqliteService) {}
/**
* Get doc entries with optional filtering to optimize memory/speed.
*/
async getDocEntries(query?: string, packageNames?: string[]) {
let sql = `
SELECT d.id, d.title, d.keywords, d.slug, s.name as package_name, s.path AS source_path
FROM doc_entries d
JOIN doc_sources s ON d.source_id = s.id
WHERE 1=1
`;
const params: any[] = [];
if (packageNames && packageNames.length > 0) {
const placeholders = packageNames.map(() => '?').join(',');
sql += ` AND s.name IN (${placeholders})`;
params.push(...packageNames);
}
if (query) {
// Basic fuzzy match in SQL to reduce result set
// Use COALESCE in case title or keywords are NULL
sql += ` AND (COALESCE(d.title, '') LIKE ? OR COALESCE(d.keywords, '') LIKE ?)`;
params.push(`%${query}%`, `%${query}%`);
}
// Limit absolute max to avoid memory crashes on massive queries
sql += ` LIMIT 1000`;
console.log(`[DocsService] Executing SQL: ${sql} with params: ${JSON.stringify(params)}`);
return await this.sqlite.query<any>(sql, params);
}
async loadDoc(docId: string) {
const entry = await this.sqlite.get<any>(
`SELECT d.id, d.title, d.slug, s.path AS source_path
FROM doc_entries d
JOIN doc_sources s ON d.source_id = s.id
WHERE d.id=?`,
[docId]
);
if (!entry) throw new Error('Doc not found');
const dbFile = path.join(entry.source_path, 'db.json');
if (!fs.existsSync(dbFile)) throw new Error('Doc database missing');
// Use cache to avoid re-parsing large JSON files
let db = this.dbContentCache.get(dbFile);
if (!db) {
console.log(`[Docs] Parsing db.json for ${entry.source_path}...`);
db = JSON.parse(fs.readFileSync(dbFile, 'utf-8'));
this.dbContentCache.set(dbFile, db);
// Basic cache eviction if it grows too large (e.g., > 3 entries)
if (this.dbContentCache.size > 3) {
const firstKey = this.dbContentCache.keys().next().value;
this.dbContentCache.delete(firstKey);
}
}
const content = db[entry.slug];
if (!content) throw new Error('Content not found in db.json');
return {
title: entry.title,
content: content, // HTML content
source_path: entry.source_path
};
}
async getRelatedDocs(docId: string) {
return await this.sqlite.query<any>(
`SELECT dr.related_doc_id AS id, d.title, dr.relation_type AS relation
FROM doc_relationships dr
JOIN doc_entries d ON dr.related_doc_id = d.id
WHERE dr.doc_id=?`,
[docId]
);
}
}
