State county mapping

script.php

<?php

// Path to your CSV file.
$csvFile = __DIR__ . '/usda.csv';

$stateCountyMapping = [];

// Read the CSV file.
if (($handle = fopen($csvFile, 'r')) !== false) {
  // Skip the header row.
  fgetcsv($handle);

  // Process each row.
  while (($row = fgetcsv($handle)) !== false) {
    if (count($row) < 2) {
      continue; // Skip invalid rows.
    }
    $state = $row[0];
    $county = $row[1];

    // Group counties by state.
    if (!isset($stateCountyMapping[$state])) {
      $stateCountyMapping[$state] = [];
    }
    $stateCountyMapping[$state][] = $county;
  }

  fclose($handle);
}

// Print the array as PHP code.
foreach ($stateCountyMapping as $state => $counties) {
  echo "  '$state' => [\n";
  foreach ($counties as $county) {
    echo "    '$county',\n";
  }
  echo "  ],\n";
}