/// <reference types="google-apps-script" />
// Apps Script adapters shared by the sending project and the checking project.
// Only this layer talks to Google; the decisions live in src/core.
import type { Grid, JournalEvent } from "../core/types";

export const TABS = {
  hiring: "Hiring",
  decisions: "Decisions",
  letter: "Welcome letter",
  journal: "Journal",
} as const;

export function prop(name: string, fallback?: string): string {
  const v = PropertiesService.getScriptProperties().getProperty(name);
  if (v === null || v === "") {
    if (fallback !== undefined) return fallback;
    throw new Error(`Script property ${name} is not set. See the setup notes.`);
  }
  return v;
}

export function tab(bookId: string, name: string): GoogleAppsScript.Spreadsheet.Sheet {
  const sheet = SpreadsheetApp.openById(bookId).getSheetByName(name);
  if (!sheet) throw new Error(`tab "${name}" not found`);
  return sheet;
}

/** Cell values as strings; dates as YYYY-MM-DD in the workbook's time zone. */
export function readGrid(sheet: GoogleAppsScript.Spreadsheet.Sheet): Grid {
  const tz = sheet.getParent().getSpreadsheetTimeZone();
  const range = sheet.getDataRange();
  return range.getValues().map((row) =>
    row.map((c) => (c instanceof Date ? Utilities.formatDate(c, tz, "yyyy-MM-dd") : String(c))),
  );
}

const JOURNAL_HEADER = ["At", "Type", "Arrival ID", "Event (JSON)"];

export function readJournal(opsBookId: string): JournalEvent[] {
  const sheet = tab(opsBookId, TABS.journal);
  const values = sheet.getDataRange().getValues();
  if (!values.length || String(values[0][0]) !== JOURNAL_HEADER[0]) throw new Error("journal header missing");
  return values
    .slice(1)
    .filter((r) => r[3])
    .map((r) => JSON.parse(String(r[3])) as JournalEvent);
}

export function appendJournal(opsBookId: string, e: JournalEvent) {
  const sheet = tab(opsBookId, TABS.journal);
  const id = "arrivalId" in e ? e.arrivalId : "";
  sheet.appendRow([e.at, e.type, id, JSON.stringify(e)]);
  // Commit the write now: Sheets may batch writes, and "attempt" must be stored BEFORE the mail call.
  // If this throws, the caller stops and no letter is sent.
  SpreadsheetApp.flush();
}

/** Same header matching as the core parser (trimmed, case-insensitive). */
export function headerColumn(header: string[], name: string): number {
  return header.findIndex((h) => String(h).trim().toLowerCase() === name.trim().toLowerCase()) + 1;
}

export function ensureJournalHeader(sheet: GoogleAppsScript.Spreadsheet.Sheet) {
  if (sheet.getLastRow() === 0) sheet.appendRow(JOURNAL_HEADER);
}

export function formatter(tz: string) {
  return (iso: string) => Utilities.formatDate(new Date(iso), tz, "EEE d MMM, h:mm a z");
}

export function installExactly(
  desired: { handler: string; kind: "every-minutes" | "daily-at-hour"; value: number }[],
  plan: (
    existing: { id: string; handler: string }[],
    installed: typeof desired | undefined,
  ) => { create: typeof desired; remove: string[] },
) {
  const props = PropertiesService.getScriptProperties();
  const raw = props.getProperty("INSTALLED_TRIGGERS");
  const triggers = ScriptApp.getProjectTriggers();
  const p = plan(
    triggers.map((t) => ({ id: t.getUniqueId(), handler: t.getHandlerFunction() })),
    raw ? (JSON.parse(raw) as typeof desired) : undefined,
  );
  for (const t of triggers) if (p.remove.includes(t.getUniqueId())) ScriptApp.deleteTrigger(t);
  for (const d of p.create) {
    const b = ScriptApp.newTrigger(d.handler).timeBased();
    if (d.kind === "every-minutes") b.everyMinutes(d.value).create();
    else b.everyDays(1).atHour(d.value).create();
  }
  props.setProperty("INSTALLED_TRIGGERS", JSON.stringify(desired));
  return {
    created: p.create.map((d) => d.handler),
    removed: p.remove.length,
    now: ScriptApp.getProjectTriggers().map((t) => t.getHandlerFunction()),
  };
}

export function authorizationStatus(): string {
  const info = ScriptApp.getAuthorizationInfo(ScriptApp.AuthMode.FULL);
  return info.getAuthorizationStatus() === ScriptApp.AuthorizationStatus.REQUIRED
    ? `REQUIRED: open ${info.getAuthorizationUrl()} as the operating account`
    : "OK";
}