'use strict';
// services/oeeStore.js — "Overall Equipment Efficiency" (OEE) data entry.
// Stored in the PORTAL's own app DB (not SAP), one document per (tab, month):
// a monthly sheet for one production area (EBB Production, PD Production, …).
// The row grid (date + shift + all the downtime/output inputs, plus the
// derived rates) is kept verbatim as a JSON array — the per-tab column schema
// and formulas live on the client (public/oee.html); the server just persists
// what it is given and enforces per-user tab permissions (see routes/oee.js).
const { getPool } = require('./appSqlPool');

const TABLE = `[dbo].[ZOEE_ENTRIES]`;

async function exec(sqlQuery, params = []) {
  const pool = await getPool();
  const req  = pool.request();
  let i = 0;
  const text = sqlQuery.replace(/\?/g, () => { const n = `p${i}`; req.input(n, params[i]); i++; return `@${n}`; });
  const result = await req.query(text);
  return result.recordset || [];
}

function isAlreadyExists(e) {
  const m = (e.message || '').toLowerCase();
  return m.includes('already exists') || m.includes('there is already an object');
}

async function bootstrap() {
  console.log('[OEE] Checking table', TABLE, '…');
  await exec(`
    CREATE TABLE ${TABLE} (
      ID          INT IDENTITY(1,1) PRIMARY KEY,
      COMPANY     NVARCHAR(100),
      TAB         NVARCHAR(50)  NOT NULL,
      MONTH       NVARCHAR(20)  NOT NULL,
      ROWS_JSON   NVARCHAR(MAX),
      REMARK      NVARCHAR(MAX),
      CANCELED    BIT DEFAULT 0,
      CREATED_BY      NVARCHAR(50),
      CREATED_BY_ID   INT,
      CREATED_AT  DATETIME2,
      UPDATED_AT  DATETIME2
    )
  `).catch(e => { if (!isAlreadyExists(e)) throw e; else console.log('[OEE] Table already exists — OK'); });
  console.log('[OEE] ✅ Ready');
}

function safeJson(v, fb) { if (!v) return fb; try { return JSON.parse(v); } catch (_e) { return fb; } }

function fromRow(r, withRows) {
  if (!r) return null;
  const o = {
    id:        r.ID,
    company:   r.COMPANY || '',
    tab:       r.TAB,
    month:     r.MONTH,
    remark:    r.REMARK || '',
    canceled:  !!r.CANCELED,
    createdBy: r.CREATED_BY || '',
    createdById: r.CREATED_BY_ID || null,
    createdAt: r.CREATED_AT ? new Date(r.CREATED_AT).toISOString() : null,
    updatedAt: r.UPDATED_AT ? new Date(r.UPDATED_AT).toISOString() : null,
    rowCount:  0,
  };
  const rows = safeJson(r.ROWS_JSON, []);
  o.rowCount = Array.isArray(rows) ? rows.length : 0;
  if (withRows) o.rows = Array.isArray(rows) ? rows : [];
  return o;
}

// List documents (headers only). Optional filters: company, tab, month, and
// an allow-set of tabs (per-user restriction — omit for no restriction).
async function list({ company, tab, month, monthFrom, monthTo, allowTabs, top = 30, skip = 0 } = {}) {
  const where = []; const params = [];
  if (company) { where.push(`COMPANY = ?`); params.push(company); }
  if (tab)     { where.push(`TAB = ?`);     params.push(tab); }
  if (month)   { where.push(`MONTH = ?`);   params.push(month); }
  if (monthFrom) { where.push(`MONTH >= ?`); params.push(monthFrom); }
  if (monthTo)   { where.push(`MONTH <= ?`); params.push(monthTo); }
  if (Array.isArray(allowTabs) && allowTabs.length) {
    where.push(`TAB IN (${allowTabs.map(() => '?').join(',')})`);
    allowTabs.forEach(t => params.push(t));
  }
  const w = where.length ? `WHERE ${where.join(' AND ')}` : '';
  const rows = await exec(
    `SELECT * FROM ${TABLE} ${w} ORDER BY ID DESC OFFSET ${Math.max(0, skip | 0)} ROWS FETCH NEXT ${Math.min(100, top | 0)} ROWS ONLY`,
    params
  );
  // Genuine total (same filter, no paging) — drives "Page X of Y" on the
  // client instead of an open-ended "Page X". Wrapped so a COUNT failure
  // never breaks the list itself — the page still loads, just without a total.
  let total = null;
  try {
    const countRows = await exec(`SELECT COUNT(*) AS n FROM ${TABLE} ${w}`, params);
    const n = Number(countRows?.[0]?.n);
    total = isNaN(n) ? null : n;
  } catch (e) { console.warn('[OEE-STORE] COUNT(*) failed — pager will show no total:', e.message); }
  return { data: rows.map(r => fromRow(r, false)), total };
}

async function getById(id) {
  const rows = await exec(`SELECT * FROM ${TABLE} WHERE ID = ?`, [parseInt(id)]);
  return rows.length ? fromRow(rows[0], true) : null;
}

// Every non-cancelled document (WITH its full row data) across a month
// range, for a report that needs to scan actual shift rows rather than just
// list documents — e.g. Downtime Analysis, which pulls every shift entry
// across every tab/machine for a date range. Unbounded (no top/skip): this
// is for server-side aggregation, not a paginated UI list.
async function listAllInRange({ company, monthFrom, monthTo } = {}) {
  const where = [`(CANCELED = 0 OR CANCELED IS NULL)`]; const params = [];
  if (company)  { where.push(`COMPANY = ?`); params.push(company); }
  if (monthFrom){ where.push(`MONTH >= ?`); params.push(monthFrom); }
  if (monthTo)  { where.push(`MONTH <= ?`); params.push(monthTo); }
  const rows = await exec(`SELECT * FROM ${TABLE} WHERE ${where.join(' AND ')}`, params);
  return rows.map(r => fromRow(r, true));
}

async function create({ company, tab, month, rows, remark, createdBy, createdById }) {
  const now = new Date().toISOString().replace('T', ' ').replace('Z', '').substring(0, 23);
  const idRows = await exec(
    `INSERT INTO ${TABLE} (COMPANY, TAB, MONTH, ROWS_JSON, REMARK, CANCELED, CREATED_BY, CREATED_BY_ID, CREATED_AT, UPDATED_AT)
     VALUES (?, ?, ?, ?, ?, 0, ?, ?, ?, ?);
     SELECT SCOPE_IDENTITY() AS ID;`,
    [company || '', tab, month, JSON.stringify(Array.isArray(rows) ? rows : []), remark || null,
     createdBy || null, createdById || null, now, now]
  );
  return idRows[0].ID;
}

async function update(id, { month, rows, remark }) {
  const sets = []; const vals = [];
  if (month  !== undefined) { sets.push('MONTH = ?');     vals.push(month); }
  if (rows   !== undefined) { sets.push('ROWS_JSON = ?');  vals.push(JSON.stringify(Array.isArray(rows) ? rows : [])); }
  if (remark !== undefined) { sets.push('REMARK = ?');    vals.push(remark || null); }
  sets.push('UPDATED_AT = ?'); vals.push(new Date().toISOString().replace('T', ' ').replace('Z', '').substring(0, 23));
  vals.push(parseInt(id));
  await exec(`UPDATE ${TABLE} SET ${sets.join(', ')} WHERE ID = ?`, vals);
}

async function cancel(id) {
  await exec(`UPDATE ${TABLE} SET CANCELED = 1, UPDATED_AT = SYSUTCDATETIME() WHERE ID = ?`, [parseInt(id)]);
}

module.exports = { bootstrap, list, getById, create, update, cancel, listAllInRange };