// SQLite state: the T3 hosts the gateway connects to, the watches paired with it, and pending
// pairing codes. The CLI and the server open the same file, and the server rereads `hosts` so a
// `wristcode host add` takes effect without a restart.

import { Database } from "bun:sqlite";

export interface HostRow {
  id: string;
  label: string;
  url: string;
  environment_id: string;
  token: string;
  token_expires_at: string | null;
  created_at: string;
}

export interface DeviceRow {
  id: string;
  name: string;
  token_hash: string;
  apns_token: string | null;
  apns_env: "sandbox" | "production" | null;
  created_at: string;
  last_seen_at: string | null;
  revoked_at: string | null;
}

const SCHEMA = `
create table if not exists hosts (
  id text primary key,
  label text not null,
  url text not null unique,
  environment_id text not null unique,
  token text not null,
  token_expires_at text,
  created_at text not null
);
create table if not exists devices (
  id text primary key,
  name text not null,
  token_hash text not null unique,
  apns_token text,
  apns_env text,
  created_at text not null,
  last_seen_at text,
  revoked_at text
);
create table if not exists pairing_codes (
  code_hash text primary key,
  expires_at text not null,
  used_at text
);
`;

export const sha256 = (value: string) => new Bun.CryptoHasher("sha256").update(value).digest("hex");

const now = () => new Date().toISOString();

export function openDb(path: string) {
  const db = new Database(path, { create: true, strict: true });
  db.run("pragma journal_mode = wal");
  db.run("pragma busy_timeout = 5000");
  db.run(SCHEMA);

  return {
    hosts: {
      list: () => db.query<HostRow, []>("select * from hosts order by created_at").all(),
      upsert(host: Omit<HostRow, "created_at">) {
        db.query(
          `insert into hosts (id, label, url, environment_id, token, token_expires_at, created_at)
           values ($id, $label, $url, $environment_id, $token, $token_expires_at, $created_at)
           on conflict(environment_id) do update set
             label = excluded.label, url = excluded.url, token = excluded.token,
             token_expires_at = excluded.token_expires_at`,
        ).run({ ...host, created_at: now() });
      },
      remove: (idOrLabel: string) =>
        db.query("delete from hosts where id = $v or label = $v").run({ v: idOrLabel }).changes > 0,
    },

    devices: {
      list: () => db.query<DeviceRow, []>("select * from devices order by created_at").all(),
      active: () => db.query<DeviceRow, []>("select * from devices where revoked_at is null").all(),
      create(name: string, token: string): string {
        const id = crypto.randomUUID();
        db.query(
          "insert into devices (id, name, token_hash, created_at) values ($id, $name, $hash, $created_at)",
        ).run({ id, name, hash: sha256(token), created_at: now() });
        return id;
      },
      /** The active device that owns this bearer token, marking it seen. */
      authenticate(token: string): DeviceRow | null {
        const device = db
          .query<DeviceRow, { hash: string }>("select * from devices where token_hash = $hash and revoked_at is null")
          .get({ hash: sha256(token) });
        if (device) db.query("update devices set last_seen_at = $at where id = $id").run({ at: now(), id: device.id });
        return device;
      },
      setPush(id: string, apnsToken: string, apnsEnv: "sandbox" | "production") {
        db.query("update devices set apns_token = $apnsToken, apns_env = $apnsEnv where id = $id").run({
          id,
          apnsToken,
          apnsEnv,
        });
      },
      clearPush: (apnsToken: string) =>
        db.query("update devices set apns_token = null where apns_token = $apnsToken").run({ apnsToken }),
      revoke: (idOrName: string) =>
        db.query("update devices set revoked_at = $at where (id = $v or name = $v) and revoked_at is null").run({
          at: now(),
          v: idOrName,
        }).changes,
    },

    pairing: {
      create(code: string, ttlMs: number) {
        db.query("insert into pairing_codes (code_hash, expires_at) values ($hash, $expires_at)").run({
          hash: sha256(code),
          expires_at: new Date(Date.now() + ttlMs).toISOString(),
        });
      },
      /** Marks the code used and returns true if it was valid. */
      redeem(code: string): boolean {
        return (
          db
            .query(
              "update pairing_codes set used_at = $at where code_hash = $hash and used_at is null and expires_at > $at",
            )
            .run({ hash: sha256(code), at: now() }).changes > 0
        );
      },
      /** Voids every open code, after too many wrong guesses. */
      voidAll: () => db.query("update pairing_codes set used_at = $at where used_at is null").run({ at: now() }),
    },

    close: () => db.close(),
  };
}

export type Db = ReturnType<typeof openDb>;