// The printers you've added.
//
// Access codes are stored here but never handed back to the browser: every
// read returns `codeSet` instead, and saving with a blank code keeps the one
// already stored.
const db = require('./db');

// Which AMS types can say how much filament is left. An AMS lite only knows
// full or empty, so its reading is never used as a weight.
const AMS_TYPES = { none: false, ams_lite: false, ams: true, ams_2_pro: true, ams_ht: true };

const clean = (value, max) => {
  const s = String(value ?? '').trim();
  return s ? s.slice(0, max) : null;
};

function publicPrinter(row) {
  if (!row) return null;
  const { access_code: accessCode, ...rest } = row;
  return { ...rest, codeSet: Boolean(accessCode) };
}

function fields(data) {
  return {
    nickname: clean(data.nickname, 60),
    model: clean(data.model, 40),
    host: clean(data.host, 255),
    serial: clean(data.serial, 40),
    ams_type: Object.prototype.hasOwnProperty.call(AMS_TYPES, data.ams_type) ? data.ams_type : null,
  };
}

async function list() {
  const { rows } = await db.query('SELECT * FROM printers ORDER BY id');
  return rows.map(publicPrinter);
}

// Server-side only: includes the access code, for connecting.
async function listWithCodes() {
  const { rows } = await db.query('SELECT * FROM printers ORDER BY id');
  return rows;
}

async function get(id, { withCode = false } = {}) {
  const { rows: [row] } = await db.query('SELECT * FROM printers WHERE id = $1', [id]);
  if (!row) return null;
  return withCode ? row : publicPrinter(row);
}

async function create(data) {
  const f = fields(data);
  const { rows: [row] } = await db.query(
    `INSERT INTO printers (nickname, model, host, serial, access_code, ams_type)
     VALUES ($1, $2, $3, $4, $5, $6) RETURNING *`,
    [f.nickname, f.model, f.host, f.serial, clean(data.access_code, 64), f.ams_type]);
  return publicPrinter(row);
}

// Only the fields sent are changed; a blank access code keeps the stored one.
async function update(id, data) {
  const f = fields(data);
  const has = (key) => Object.prototype.hasOwnProperty.call(data, key);
  const { rows: [row] } = await db.query(
    `UPDATE printers SET
       nickname      = CASE WHEN $2::boolean THEN $3 ELSE nickname END,
       model         = CASE WHEN $4::boolean THEN $5 ELSE model END,
       host          = CASE WHEN $6::boolean THEN $7 ELSE host END,
       serial        = CASE WHEN $8::boolean THEN $9 ELSE serial END,
       ams_type      = CASE WHEN $10::boolean THEN $11 ELSE ams_type END,
       access_code   = COALESCE($12, access_code),
       date_modified = now()
     WHERE id = $1 RETURNING *`,
    [id, has('nickname'), f.nickname, has('model'), f.model, has('host'), f.host,
      has('serial'), f.serial, has('ams_type'), f.ams_type, clean(data.access_code, 64)]);
  return publicPrinter(row);
}

// Removing a printer also marks its spools as no longer loaded anywhere.
async function remove(id) {
  const { rows: [row] } = await db.query('DELETE FROM printers WHERE id = $1 RETURNING serial', [id]);
  if (!row) return false;
  if (row.serial) {
    await db.query('UPDATE filament_spools SET ams_slot = NULL WHERE printer_serial = $1', [row.serial]);
  }
  return true;
}

const measures = (amsType) => Boolean(AMS_TYPES[amsType]);

module.exports = { AMS_TYPES, list, listWithCodes, get, create, update, remove, measures, publicPrinter };