import { DynamoDBClient } from "@aws-sdk/client-dynamodb";
import { DynamoDBDocumentClient, ScanCommand } from "@aws-sdk/lib-dynamodb";
import { readFileSync, writeFileSync, mkdirSync } from "fs";
import { execSync } from "child_process";

mkdirSync("output", { recursive: true });

// Get all PO numbers from DynamoDB
const client = new DynamoDBClient({ region: "us-east-1" });
const docClient = DynamoDBDocumentClient.from(client);

const dbPOs = new Set();
let lastKey = undefined;

console.log("Scanning DynamoDB for existing PO numbers...");
while (true) {
  const resp = await docClient.send(
    new ScanCommand({
      TableName: "purchase-orders",
      ProjectionExpression: "po_number",
      ExclusiveStartKey: lastKey,
    })
  );
  for (const item of resp.Items) {
    dbPOs.add(item.po_number);
  }
  lastKey = resp.LastEvaluatedKey;
  if (!lastKey) break;
}
console.log(`Found ${dbPOs.size} POs in DynamoDB`);

// Get POs from invoice spreadsheet using python helper
console.log("Extracting POs from invoice spreadsheet...");
const pyScript = [
  "import openpyxl, json",
  'wb = openpyxl.load_workbook("/Users/adammoussa/Documents/working-docs/plumbing-spend/invoices-2025.xlsx")',
  "ws = wb.active",
  "pos = set()",
  "for row in ws.iter_rows(min_row=2, values_only=True):",
  "    if row[1]: pos.add(str(row[1]).strip())",
  "print(json.dumps(sorted(list(pos))))",
].join("\n");
const invoicePOs = JSON.parse(
  execSync(`python3.12 -c "${pyScript.replace(/"/g, '\\"')}"`, { encoding: "utf-8" })
);
console.log(`Found ${invoicePOs.length} unique POs in invoice file`);

// Find POs not in DB
const notInDb = invoicePOs.filter((po) => !dbPOs.has(po));
console.log(`POs not in DynamoDB: ${notInDb.length}`);

writeFileSync("output/po-list.json", JSON.stringify(notInDb, null, 2));
console.log("Saved to output/po-list.json");