#!/usr/bin/env node

/*

*

* This script checks for missing ONS Codes in the ONS Postcode Directory

*

* To run: find_missing.js /path/to/postcode/directory.csv

*

* This parses every line of the directory returns result to stdout

*

*/

"use strict";

const fs = require("fs");

const path = require("path");

const csv = require("csv");

const parse = csv.parse;

const transform = csv.transform;

const argv = require('minimist')(process.argv.slice(2));

const codeTypes = [

"nhsHa",

"counties",

"districts",

"wards",

"parishes",

"constituencies",

"european_registers",

"regions",

"pcts",

"lsoa",

"msoa",

"nuts",

"ccgs"

];

const typeOffset = {

nhsHa: 12,

counties: 5,

districts: 6,

wards: 7,

parishes: 44,

constituencies: 17,

european_registers: 18,

regions: 15,

pcts: 21,

lsoa: 42,

msoa: 43,

nuts: 22,

ccgs: 46

};

const source = argv._[0];

if (!source || !fs.existsSync(source)) {

console.log("Please specificy ONSPD Directory source file");

process.exit(0);

}

const type = argv.type;

if (type) {

if (!codeTypes.some(codeType => codeType === type )) {

console.log("Please specify a valid code type using --type=", codeTypes);

process.exit(0);

} else {

codeTypes = [type];

}

}

// Load data sources

const data = {};

const missingData = {};

codeTypes.forEach(codeType => {

missingData[codeType] = {};

data[codeType] = require(`../data/${codeType}.json`);

});

const check = (row, type) => {

const elem = row[typeOffset[type]];

if (elem === "") {

return;

} else {

if (typeof data[type][elem] === 'undefined') {

if (typeof missingData[type][elem] !== 'number') {

missingData[type][elem] = 0;

} else {

missingData[type][elem] += 1;

}

}

}

};

const parser = parse({delimiter: ","});

fs.createReadStream(source)

.pipe(parser)

.on("data", row => {

if (row[4].length !== 0) return null; // Skip row if terminated postcode

codeTypes.forEach(codeType => check(row, codeType));

})

.on("end", () => {

console.log(JSON.stringify(missingData, 2, 2));

process.exit(0);

})

.on("error", error => {

console.log(error.message);

process.exit(1);

});