blueprint.js

const Blueprint = require('factorio-blueprint');

const bp = new Blueprint();

Blueprint.setEntityData({
  'aai_strongbox_passive_provider':
  {
    type: 'item', // 'item', 'fluid', 'virtual', 'tile', or 'recipe'
    width: 2,
    height: 2,
    recipe: true,
    modules: 4,
    inventorySize: 96, // How many slots this container has (such as a chest)
    filterAmount: false, // Set to false for filter inserters which have filters but no "amounts" on the filters
    directionType: false // true for underground belts
  }
});
let startY = 1;
let segment = 1;
let flipped = false;
let lastSubstation;
//Start with some substations
for (let i = 0; i < 40; i += 18) {
  flipped = (segment % 2 == 0) ? true : false;
  let lastSegment = (i + 18 < 40) ? true : false;
  let topDirection = flipped ? Blueprint.RIGHT : Blueprint.LEFT;
  let bottomDirection = flipped ? Blueprint.LEFT : Blueprint.RIGHT;
  let midDirection = flipped ? Blueprint.DOWN : Blueprint.UP;

  bp.createEntity('fast_underground_belt', { x: i, y: startY - 1} , Blueprint.DOWN);
  bp.createEntity('fast_underground_belt', { x: i+1, y: startY - 1} , Blueprint.DOWN);

  let substation = bp.createEntity('substation', { x: i, y: startY }, Blueprint.RIGHT);
  if (lastSubstation) {
    substation.connect(lastSubstation, null, null, 'red');
    substation.connect(lastSubstation, null, null, 'green');
  }
  lastSubstation = substation;
  if (flipped) {
    bp.createEntity('fast_underground_belt', { x: i, y: startY + 2} , Blueprint.DOWN).setDirectionType('output');
    bp.createEntity('fast_underground_belt', { x: i+1, y: startY + 2} , Blueprint.DOWN).setDirectionType('output');
  } else {
    bp.createEntity('fast_underground_belt', { x: i, y: startY + 2} , Blueprint.UP);
    bp.createEntity('fast_underground_belt', { x: i+1, y: startY + 2} , Blueprint.UP);
  }
    // Put 2x2 boxes between them

  if (lastSegment) {
    for (let j = 2; j < 18; j +=2 ) {
      bp.createEntity('aai_strongbox_passive_provider', { x: j + i, y: startY + 1}, Blueprint.RIGHT);
      bp.createEntity('aai_strongbox_passive_provider', { x: j + i, y: startY - 1}, Blueprint.RIGHT);
      if (flipped) {
        bp.createEntity('stack_filter_inserter', { x: j + i, y: startY + 3 }, Blueprint.UP);
        bp.createEntity('stack_inserter', { x: j + i + 1, y: startY + 3 }, Blueprint.DOWN);
        bp.createEntity('stack_filter_inserter', { x: j + i, y: startY - 2 }, Blueprint.DOWN);
        bp.createEntity('stack_inserter', { x: j + i + 1, y: startY - 2 }, Blueprint.UP);
      } else {
        bp.createEntity('stack_filter_inserter', { x: j + i + 1, y: startY + 3 }, Blueprint.DOWN);
        bp.createEntity('stack_inserter', { x: j + i, y: startY + 3 }, Blueprint.UP);
        bp.createEntity('stack_filter_inserter', { x: j + i + 1, y: startY - 2 }, Blueprint.DOWN);
        bp.createEntity('stack_inserter', { x: j + i, y: startY - 2 }, Blueprint.UP);
      }
    }
 
  // Add belts


    for (let k = 2; k < 18; k++) {
      bp.createEntity('fast_transport_belt', { x: k + i, y: 5}, topDirection);
      bp.createEntity('fast_transport_belt', { x: k + i, y: -2}, bottomDirection);

    }
  
 
}
if (!flipped) {
  bp.createEntity('fast_transport_belt', { x: 1 + i, y: -2}, Blueprint.RIGHT);
  bp.createEntity('fast_transport_belt', { x: i, y: -2}, Blueprint.LEFT);
  bp.createEntity('fast_transport_belt', { x: i, y: 5}, midDirection);
  bp.createEntity('fast_transport_belt', { x: 1 + i, y: 5}, midDirection);
} else {
  bp.createEntity('fast_transport_belt', { x: 1 + i, y: -2}, midDirection);
  bp.createEntity('fast_transport_belt', { x: i, y: -2}, midDirection);
  bp.createEntity('fast_transport_belt', { x: i, y: 5}, Blueprint.LEFT);
  bp.createEntity('fast_transport_belt', { x: 1 + i, y: 5}, Blueprint.RIGHT);
}

bp.createEntity('fast_transport_belt', { x: 1 + i, y: 4}, midDirection);
bp.createEntity('fast_transport_belt', { x: 1 + i, y: -1}, midDirection);


bp.createEntity('fast_transport_belt', { x: i, y: 4}, midDirection);
bp.createEntity('fast_transport_belt', { x: i, y: -1}, midDirection);

  segment++;
}





// Center the blueprint around the entities instead of position (0,0)
bp.fixCenter();

// Output the blueprint string!
console.log(bp.encode({version: 'latest', autoConnectPoles: true}));