/// <reference types="google-apps-script" />
// The SENDING project. Runs under the dedicated sending account, every 15 minutes.
// Reads the hiring workbook (edited by the team), writes only the Arrival ID cell
// of new rows, and appends to the journal workbook (not edited by the team).
import { planTriggers } from "../core/triggers";
import { runPass as corePass, type PassReport } from "../core/pass";
import { parseDecisions, parseHiring } from "../core/schema";
import { HIRING_COLUMNS, type HiringSource, type Journal, type LetterTemplate, type MailSender, type PassConfig } from "../core/types";
import { appendJournal, authorizationStatus, headerColumn, installExactly, prop, readGrid, readJournal, tab, TABS } from "./common";

const MANAGED = ["runPass"];

function hiringBook() {
  return prop("HIRING_BOOK_ID");
}
function opsBook() {
  return prop("OPS_BOOK_ID");
}

/** The team edits the letter and the on/paused switch in the "Welcome letter" tab. */
export function readLetterSettings(): { letter: LetterTemplate; paused: boolean } {
  const rows = readGrid(tab(hiringBook(), TABS.letter));
  const kv = new Map(rows.map((r) => [String(r[0]).trim().toLowerCase(), String(r[1] ?? "")]));
  const need = (k: string) => {
    const v = kv.get(k);
    if (!v) throw new Error(`"${k}" is empty in the Welcome letter tab`);
    return v;
  };
  return {
    letter: { subject: need("subject"), body: need("body"), senderName: need("sender name"), replyTo: need("reply-to") },
    paused: (kv.get("sending") ?? "").trim().toLowerCase() !== "on",
  };
}

export function sheetSource(): HiringSource {
  return {
    readHiring: () => readGrid(tab(hiringBook(), TABS.hiring)),
    readDecisions: () => readGrid(tab(hiringBook(), TABS.decisions)),
    writeArrivalId(rowNumber, expected, id) {
      const sheet = tab(hiringBook(), TABS.hiring);
      const header = sheet.getRange(1, 1, 1, sheet.getLastColumn()).getValues()[0].map((h) => String(h).trim());
      const col = (name: string) => headerColumn(header, name);
      if (!col(HIRING_COLUMNS.therapist) || !col(HIRING_COLUMNS.welcomeEmail) || !col(HIRING_COLUMNS.arrivalId)) return false;
      const row = sheet.getRange(rowNumber, 1, 1, header.length).getValues()[0].map(String);
      if (row[col(HIRING_COLUMNS.therapist) - 1].trim() !== expected.therapist) return false;
      if (row[col(HIRING_COLUMNS.welcomeEmail) - 1].trim() !== expected.welcomeEmail) return false;
      if (row[col(HIRING_COLUMNS.arrivalId) - 1].trim()) return false;
      sheet.getRange(rowNumber, col(HIRING_COLUMNS.arrivalId)).setValue(id);
      return true;
    },
  };
}

export function mailSender(): MailSender {
  return {
    send: (l) => MailApp.sendEmail({ to: l.to, subject: l.subject, body: l.body, name: l.senderName, replyTo: l.replyTo }),
    remainingQuota: () => MailApp.getRemainingDailyQuota(),
  };
}

export function passConfig(): PassConfig {
  const { letter, paused } = readLetterSettings();
  return {
    mode: prop("MODE", "dry-run") === "live" ? "live" : "dry-run",
    scopeFromStartDate: prop("SCOPE_FROM_START_DATE"),
    sendingPaused: paused,
    letter,
  };
}

export function runPassNow(overrides: { source?: HiringSource; sender?: MailSender; journal?: Journal } = {}): PassReport {
  const lock = LockService.getScriptLock();
  return corePass(
    {
      source: overrides.source ?? sheetSource(),
      sender: overrides.sender ?? mailSender(),
      journal: overrides.journal ?? sheetJournal(),
      clock: { now: () => new Date() },
      lock: {
        tryAcquire: () => lock.tryLock(20000),
        release: () => {
          SpreadsheetApp.flush(); // pending writes are committed before another execution can start
          lock.releaseLock();
        },
      },
    },
    passConfig(),
  );
}

export function sheetJournal(): Journal {
  return { read: () => readJournal(opsBook()), append: (e) => appendJournal(opsBook(), e) };
}

export function install() {
  const every = Number(prop("PASS_EVERY_MINUTES", "15"));
  const desired = [{ handler: "runPass", kind: "every-minutes" as const, value: every }];
  return installExactly(desired, (existing, installed) => planTriggers(existing, desired, MANAGED, undefined, installed));
}

/** Run after every code change, as the operating account. Changes nothing. */
export function verify() {
  const out: Record<string, string> = { authorization: authorizationStatus() };
  try {
    const h = parseHiring(readGrid(tab(hiringBook(), TABS.hiring)));
    out.hiringSheet = h.ok ? `OK (${h.rows.length} rows)` : `MISSING COLUMNS: ${h.missing.join(", ")}`;
    const d = parseDecisions(readGrid(tab(hiringBook(), TABS.decisions)));
    out.decisionsTab = d.ok ? "OK" : `MISSING COLUMNS: ${d.missing.join(", ")}`;
    const s = readLetterSettings();
    out.letter = `OK (${s.letter.subject})`;
    out.sending = s.paused ? "PAUSED" : "ON";
    out.journal = `OK (${readJournal(opsBook()).length} events)`;
  } catch (e) {
    out.error = (e as Error).message;
  }
  out.mode = prop("MODE", "dry-run");
  out.triggers = ScriptApp.getProjectTriggers().map((t) => t.getHandlerFunction()).join(", ") || "none";
  out.mailQuotaLeft = String(MailApp.getRemainingDailyQuota());
  return out;
}