let SiteScrape = module.exports = {}

//
// $ = the cheerio scrape object
//

const removeWhitespace = /\s+/g

const commonWords = ['share','facebook','twitter','reddit','be','have','do','say','get','make','go','know','take','see','come','think','look','want',
		'give','use','find','tell','ask','work','seem','feel','try','leave','call','good','new','first','last','long','great','little','own','other','old',
		'right','big','high','different','small','large','next','early','young','important','few','public','bad','same','able','to','of','in','for','on',
		'with','at','by','from','up','about','into','over','after','the','and','a','that','I','it','not','he','as','you','this','but','his','they','her',
		'she','or','an','will','my','one','all','would','there','their','and','that','but','or','as','if','when','than','because','while','where','after',
		'so','though','since','until','whether','before','although','nor','like','once','unless','now','except','are','also','is','your','its']

SiteScrape.getTitle = ($) => {

	let title = $('title').text().replace(removeWhitespace, " ")
	return title

}

//Finds all urls in text, removes duplicates, makes sure they have https://
SiteScrape.getCleanUrls = (textBlock) => {
	//Find all URLs in text
	//@TODO - Use the process text library for this function
	const urlPattern = /(?:(?:https?|ftp|file):\/\/|www\.|ftp\.)(?:\([-A-Z0-9+&@#/%=~_|$?!:,.]*\)|[-A-Z0-9+&@#/%=~_|$?!:,.])*(?:\([-A-Z0-9+&@#/%=~_|$?!:,.]*\)|[A-Z0-9+&@#/%=~_|$])/igm
	let allUrls = textBlock.match(urlPattern)

	if(allUrls == null){
		return []
	}

	//Every URL needs HTTPS!!!
	let foundUrls = []
	allUrls.forEach( (item, index) => {
		//add protocol if it is missing
		if(item.indexOf('https://') == -1 && item.indexOf('http://') == -1){
			allUrls[index] = 'https://'+item
		}
		//convert http to https
		if(item.indexOf('http://') >= 0){
			allUrls[index] = item.replace('http://','https://')
		}
	})

	//Remove all duplicates
	foundUrls = [...new Set(allUrls)]

	return foundUrls
}

//Site hostname with https:// eg: https://www.google.com
SiteScrape.getHostName = (url) => {

	var hostname = 'https://'+(new URL(url)).hostname;
	console.log('hostname', hostname)
	return hostname
}

// URL for image that can be downloaded to represent website
SiteScrape.getDisplayImage = ($, url) => {

	const hostname = SiteScrape.getHostName(url)

	let metaImg = $('meta[property="og:image"]')
	let shortcutIcon = $('link[rel="shortcut icon"]')
	let favicon = $('link[rel="icon"]')
	let randomImg = $('img')

	console.log('----')

	//Scrape metadata for page image
	//Grab the first random image we find
	if(randomImg && randomImg[0] && randomImg[0].attribs){
		thumbnail = hostname + randomImg[0].attribs.src
		console.log('random img '+thumbnail)
	}
	//Grab the favicon of the site
	if(favicon && favicon[0] && favicon[0].attribs){
		thumbnail = hostname + favicon[0].attribs.href
		console.log('favicon '+thumbnail)
	}
	//Grab the shortcut icon
	if(shortcutIcon && shortcutIcon[0] && shortcutIcon[0].attribs){
		thumbnail = hostname + shortcutIcon[0].attribs.href
		console.log('shortcut '+thumbnail)
	}
	//Grab the presentation image for the site
	if(metaImg && metaImg[0] && metaImg[0].attribs){
		thumbnail = metaImg[0].attribs.content
		console.log('ogImg '+thumbnail)
	}

	console.log('-----')
	return thumbnail
}

// Get all the site text and parse out the words that appear most
SiteScrape.getKeywords = ($) => {

	let majorContent = ''

	majorContent += $('[class*=content]').text()
		.replace(removeWhitespace, " ") //Remove all whitespace
		.replace(/\W\s/g, '') //Remove all non alphanumeric characters
		.substring(0,3000) //Limit to 3000 characters
		.toLowerCase()

	//Count frequency of each word in scraped text
	let frequency = {}
	majorContent.split(' ').forEach(word => {
		if(commonWords.includes(word)){
			return //Exclude certain words
		}
		if(!frequency[word]){
			frequency[word] = 0
		}
		frequency[word]++
	})

	//Create a sortable array
	var sortable = [];
	for (var index in frequency) {
		if(frequency[index] > 1){
			sortable.push([index, frequency[index]]);
		}
	}

	//Sort them by most used words in the list
	sortable.sort(function(a, b) {
		return b[1] - a[1];
	});

	let finalWords = []
	for(let i=0; i<5; i++){
		if(sortable[i] && sortable[i][0]){
			finalWords.push(sortable[i][0]) 
		}
	}

	if(finalWords.length > 0){
		return 'Keywords: ' + finalWords.join(', ')
	}
	return ''
}

SiteScrape.getMainText = ($) => {}