const fs = require('fs')
var path = require('path')

// settings
const ignoreFiles = ['_navbar.md', '_sidbar.md']
const basePath = '/'
const basePathAssets = './'
const uriSuffix = '.html'
const anchorPrefix = '#'
const assetsFolder = 'assets'
const gitUrl = 'https://github.com/Mint-System/Knowledge/blob/master/'
const wikiImage = /!\[\[([^\]]*\.png|jpg|jpeg|svg|gif)\]\]/g
const embededContent = /!\[\[([^\]]*)\]\]/g
const wikiLink = /\[\[([^\]]*)\]\]/g 

function sanitizeName(file) {
    return file.toLocaleLowerCase()
        .replace(/\s+/g, '-')
        .replace('---','-')
}

function sanitizeAssetname(file) {
    return file.toLocaleLowerCase()
        .replace(/\s+/g, '-')
        .replace('---','-')
        .replace(/ö/g,'o')
        .replace(/ü/g,'u')
        .replace(/ä/g,'a')
}

function convert(content,file) {

    // convert wiki image links
    // ![[image.png]] -> <img src="./assets/image.png"/>
    let matches = content.match(wikiImage) || []
    for (i = 0; i < matches.length; i++) {
        let match = matches[i]
        let image = sanitizeAssetname(match.match(/!\[\[([^\]]*)/)[1])
        content = content.replace(match, `![](${basePathAssets}${image})`)
    }

    // convert embeded content links
    // ![[Content]] -> [Content](Content.md ':include')
    matches = content.match(embededContent) || []
    for (i = 0; i < matches.length; i++) {
        let match = matches[i]
        let title = encodeURI(match.match(/\[\[([^\]|#]*)/)[1])
        content = content.replace(embededContent, `[$1](${title}.md ':include')`)
    }

    // convert wiki links
    // [[href#anchor|title] -> [title](href#anchor)
    matches = content.match(wikiLink) || []
    for (i = 0; i < matches.length; i++) {
        let match = matches[i]

        let href = match.match(/\[\[([^\]|#]*)/)[1]
        let title = match.match(/\[\[([^\]|#]*)/)[1]
        let anchor = null

        // set anchor
        if (match.indexOf('#') > 0) {
            anchor = match.match(/#([^\||\]]*)/)[1]
            // sanitize anchor link
            anchor = sanitizeName(anchor)
        }

        // set title and href
        if (match.indexOf('|') > 0) {
            href = match.match(/\[\[([^\||#]*)/)[1]
            title = match.match(/\|(.*)\]\]/)[1]
        }

        // sanitize href
        href = sanitizeName(href ? href : file.replace('\.md', ''))

        let mdLink = `[${title}](${basePath}${href}${uriSuffix}${anchor ? (anchorPrefix + anchor) : ''})`
        content = content.replace(match, mdLink)
    }

    return content
}

links = []

// loop all markdown files
fs.readdirSync(__dirname).filter(file => (file.slice(-3) === '.md') && (ignoreFiles.indexOf(file) != 0)).forEach((file) => {
    
    // get markdown content
    var content = fs.readFileSync(file, 'utf8')

    // get wiki links
    matches = content.match(wikiLink) || []

    // create backlink list
    for (i = 0; i < matches.length; i++) {
        let match = matches[i]
        links.push({ source: file.replace('\.md', ''), target: match.match(/\[\[([^\]|#]*)/)[1] })
    }
    
})

// process all markdown files
fs.readdirSync(__dirname).filter(file => (file.slice(-3) === '.md') && (ignoreFiles.indexOf(file) != 0)).forEach((file) => {

    // get markdown content
    let content = fs.readFileSync(file, 'utf8')

    // set new file name
    let newfile = sanitizeName(file)

    // Get file name
    let fileName = file.replace('\.md', '')

    // convert content
    content = convert(content, file)

    // get backlinks
    let backLinks = links.filter(link => link.target === fileName)

    content = content + [
        '\n',
        '\n',
        '<footer class="page-edit">\n',
        '\n',
    ].join('')

    // add banklinks
    if(backLinks.length > 0) {
        content = content + [
            'Backlinks:\n',
            '\n',
            backLinks.map((link) => {
                let target = link.source != 'README' ? `${basePath}${sanitizeName(link.source)}${uriSuffix}` : '/'
                return `* [${link.source}](${target}) \n`
            }).join(''),
            '\n',
        ].join('')
    }

    // add footer
    content = content + [
        '[📝 Edit on GitHub](' + gitUrl + file.replace(/\s+/g, '%20') + ')\n',
        '\n',
        'Copyright © [Mint System GmbH](https://www.mint-system.ch)\n',
        '\n',
        '</footer>'
    ].join('')

    // Delete existing file
    fs.unlinkSync(file)

    // write content to new file
    fs.writeFileSync(newfile, content, 'utf8')
})

// Loop all asset files
fs.readdirSync(path.join(__dirname, assetsFolder)).forEach((file) => {
    
    // set new file name
    newfile = sanitizeAssetname(file)

    // move asset file
    fs.renameSync(path.join(__dirname, assetsFolder,file), path.join(__dirname, newfile))
})