// Runtime adapter for SQLite — works under both Bun and Node.
//
// - Bun: uses built-in `bun:sqlite`
// - Node: uses `better-sqlite3`
//
// The interfaces are intentionally tiny so the wrapping cost is minimal.

export interface Statement {
  run(...params: unknown[]): { lastInsertRowid: number | bigint; changes: number };
  get(...params: unknown[]): unknown;
  all(...params: unknown[]): unknown[];
}

export interface DbHandle {
  exec(sql: string): void;
  prepare(sql: string): Statement;
  close(): void;
}

export async function openDatabase(path: string): Promise<DbHandle> {
  // Bun runtime check.
  // eslint-disable-next-line @typescript-eslint/no-explicit-any
  const isBun = typeof (globalThis as any).Bun !== "undefined";
  if (isBun) {
    const mod = await import("bun:sqlite");
    return new BunAdapter(new mod.Database(path));
  }
  // Node runtime.
  const mod = await import("better-sqlite3");
  const DbCtor = (mod as unknown as { default: new (p: string) => unknown }).default;
  return new BetterAdapter(new (DbCtor as new (p: string) => unknown)(path) as unknown as BetterLike);
}

// ── Bun adapter ────────────────────────────────────────────────────────────

interface BunStmt {
  run(...params: unknown[]): { lastInsertRowid: number | bigint; changes: number };
  get(...params: unknown[]): unknown;
  all(...params: unknown[]): unknown[];
}

interface BunDb {
  exec(sql: string): void;
  prepare(sql: string): BunStmt;
  close(): void;
}

class BunAdapter implements DbHandle {
  constructor(private db: BunDb) {}
  exec(sql: string): void {
    this.db.exec(sql);
  }
  prepare(sql: string): Statement {
    return this.db.prepare(sql);
  }
  close(): void {
    this.db.close();
  }
}

// ── better-sqlite3 adapter ──────────────────────────────────────────────────

interface BetterStmt {
  run(...params: unknown[]): { lastInsertRowid: number | bigint; changes: number };
  get(...params: unknown[]): unknown;
  all(...params: unknown[]): unknown[];
}

interface BetterLike {
  exec(sql: string): void;
  prepare(sql: string): BetterStmt;
  pragma(s: string): unknown;
  close(): void;
}

class BetterAdapter implements DbHandle {
  constructor(private db: BetterLike) {
    this.db.pragma("journal_mode = WAL");
  }
  exec(sql: string): void {
    this.db.exec(sql);
  }
  prepare(sql: string): Statement {
    return this.db.prepare(sql);
  }
  close(): void {
    this.db.close();
  }
}