#!/usr/bin/env node

import chalk from 'chalk';
import * as fs from 'fs';
import { sync as globSync } from 'glob';
import * as Handlebars from 'handlebars';
import * as _ from 'lodash';
import * as mkdirp from 'mkdirp';
import * as yargs from 'yargs';

import toSnakeCase = require('to-snake-case');
import * as Web3 from 'web3';

import { ContextData, ParamKind } from './types';
import { utils } from './utils';

const ABI_TYPE_CONSTRUCTOR = 'constructor';
const ABI_TYPE_METHOD = 'function';
const ABI_TYPE_EVENT = 'event';
const MAIN_TEMPLATE_NAME = 'contract.mustache';

const args = yargs
	.option('abiGlob', {
		describe: 'Glob pattern to search for ABI JSON files',
		type: 'string',
		demand: true,
	})
	.option('templates', {
		describe: 'Folder where to search for templates',
		type: 'string',
		demand: true,
	})
	.option('output', {
		describe: 'Folder where to put the output files',
		type: 'string',
		demand: true,
	}).argv;

function writeOutputFile(name: string, renderedTsCode: string): void {
	const fileName = toSnakeCase(name);
	const filePath = `${args.output}/${fileName}.ts`;
	fs.writeFileSync(filePath, renderedTsCode);
	utils.log(`Created: ${chalk.bold(filePath)}`);
}

Handlebars.registerHelper('parameterType', utils.solTypeToTsType.bind(utils, ParamKind.Input));
Handlebars.registerHelper('returnType', utils.solTypeToTsType.bind(utils, ParamKind.Output));
const partialTemplateFileNames = globSync(`${args.templates}/partials/**/*.mustache`);
for (const partialTemplateFileName of partialTemplateFileNames) {
	const namedContent = utils.getNamedContent(partialTemplateFileName);
	Handlebars.registerPartial(namedContent.name, namedContent.content);
}

const mainTemplate = utils.getNamedContent(`${args.templates}/${MAIN_TEMPLATE_NAME}`);
const template = Handlebars.compile<ContextData>(mainTemplate.content);
const abiFileNames = globSync(args.abiGlob);
if (_.isEmpty(abiFileNames)) {
	utils.log(`${chalk.red(`No ABI files found.`)}`);
	utils.log(`Please make sure you've passed the correct folder name and that the files have
               ${chalk.bold('*.json')} extensions`);
	process.exit(1);
} else {
	utils.log(`Found ${chalk.green(`${abiFileNames.length}`)} ${chalk.bold('ABI')} files`);
	mkdirp.sync(args.output);
}
for (const abiFileName of abiFileNames) {
	const namedContent = utils.getNamedContent(abiFileName);
	utils.log(`Processing: ${chalk.bold(namedContent.name)}...`);
	const parsedContent = JSON.parse(namedContent.content);
	const ABI = _.isArray(parsedContent)
		? parsedContent // ABI file
		: parsedContent.abi; // Truffle contracts file
	if (_.isUndefined(ABI)) {
		utils.log(`${chalk.red(`ABI not found in ${abiFileName}.`)}`);
		utils.log(`Please make sure your ABI file is either an array with ABI entries or an object with the abi key`);
		process.exit(1);
	}

	let ctor = ABI.find((abi: Web3.AbiDefinition) => abi.type === ABI_TYPE_CONSTRUCTOR) as Web3.ConstructorAbi;
	if (_.isUndefined(ctor)) {
		ctor = utils.getEmptyConstructor(); // The constructor exists, but it's implicit in JSON's ABI definition
	}

	const methodAbis = ABI.filter((abi: Web3.AbiDefinition) => abi.type === ABI_TYPE_METHOD) as Web3.MethodAbi[];
	const methodsData = _.map(methodAbis, methodAbi => {
		_.map(methodAbi.inputs, input => {
			if (_.isEmpty(input.name)) {
				// Auto-generated getters don't have parameter names
				input.name = 'index';
			}
		});
		// This will make templates simpler
		const methodData = {
			...methodAbi,
			singleReturnValue: methodAbi.outputs.length === 1,
		};
		return methodData;
	});

	const eventAbis = ABI.filter((abi: Web3.AbiDefinition) => abi.type === ABI_TYPE_EVENT) as Web3.EventAbi[];

	const contextData = {
		contractName: namedContent.name,
		ctor,
		methods: methodsData,
		events: eventAbis,
	};
	const renderedTsCode = template(contextData);
	writeOutputFile(namedContent.name, renderedTsCode);
}