const os = require('os')
const bytes = require('bytes')
const sharp = require('sharp')
const morgan = require('morgan')
const express = require('express')
const PDFDocument = require('pdfkit')

const app = express()
app.set('json spaces', 4)
app.use(morgan('dev'))
app.use(express.json())

app.all('/', (req, res) => {
	const status = {}
	const used = process.memoryUsage()
	for (let key in used) status[key] = formatSize(used[key])
	
	const totalmem = os.totalmem()
	const freemem = os.freemem()
	status.memoryUsage = `${formatSize(totalmem - freemem)} / ${formatSize(totalmem)}`
	
	res.json({
		creator: '@rippanteq7',
		message: 'Hello World',
		uptime: new Date(process.uptime() * 1000).toUTCString().split(' ')[4],
		status
	})
})

app.post('/imagetopdf', async (req, res) => {
	try {
		console.log(req.body)
		const { images } = req.body
		if (!images) return res.json({ success: false, message: 'Required an array image url' })
		
		const buffer = await toPDF(images)
		res.setHeader('Content-Disposition', `attachment; filename=${Math.random().toString(36).slice(2)}.pdf`)
		res.setHeader('Content-Type', 'application/pdf')
		res.setHeader('Content-Length', buffer.byteLength)
		res.send(buffer)
	} catch (e) {
		console.log(e)
		e = String(e)
		res.json({ error: true, message: e === '[object Object]' ? 'Internal Server Error' : e })
	}
})

const PORT = process.env.PORT || 7860
app.listen(PORT, () => console.log('App running on port', PORT))

function formatSize(num) {
	return bytes.format(+num || 0, { unitSeparator: ' ' })
}

function toPDF(urls) {
	return new Promise(async (resolve, reject) => {
		try {
			if (!Array.isArray(urls)) urls = [urls]
			const doc = new PDFDocument({ margin: 0, size: 'A4' })
			const buffers = []
			
			const promises = urls.map(async (url, index) => {
				const response = await fetch(url, { headers: { referer: url }})
				if (!response.ok) return
				
				const type = response.headers.get('content-type')
				if (!/image/.test(type)) return reject(`Invalid Type: ${type}`)
				
				let buffer = Buffer.from(await response.arrayBuffer())
				if (/gif|webp/.test(type)) buffer = await sharp(buffer).png().toBuffer()
				
				doc.image(buffer, 0, 0, { fit: [595.28, 841.89], align: 'center', valign: 'center' })
				if (urls.length !== index + 1) doc.addPage()
			})
			
			await Promise.all(promises)
			
			doc.on('data', (chunk) => buffers.push(chunk))
			doc.on('end', () => resolve(Buffer.concat(buffers)))
			doc.on('error', reject)
			doc.end()
		} catch (e) {
			console.log(e)
			reject(e)
		}
	})
}