const fs = require('fs');
const path = require("path")
const { XMLParser } = require("fast-xml-parser")

const appendOptionalSpace = (nextObject) => {
    const punctuation = [".", ",", "?", ":", "!"]
    if (nextObject)  {
        
        const nextString = produceString(nextObject)

        
        if (punctuation.includes(nextString.trim().at(0))) {
            return ""
        } 
        if (nextString.startsWith("—")) {
            return ""
        }
        return " "
    }

    return ""
}
const produceString = (xmlObject, references = [], nextObject = null, level = 1) => {
    if (Array.isArray(xmlObject)) {
        const array = xmlObject.map((object, index, array) => {
            return produceString(object, references, array[index+1])
        })
        return array.join("")
    } else {
        const keys = Object.keys(xmlObject)
        // console.log("Keys: ", keys)
        return keys.map((key, index, array) => {
            if (key == "component") {
                return produceString(xmlObject[key].slice(3), references)
            } else if (key == "header") {
                return produceString(xmlObject[key], references)
            } else if (key =="contentMeta") {
                return produceString(xmlObject[key], references)
            } else if (key =="titleGroup") {
                return produceString(xmlObject[key], references)
            } else if (key =="title") {
                return `# ${produceString(xmlObject[key], references)}`
            } else if (key =="body") {
                return produceString(xmlObject[key], references)
            } else if (key == "?xmltex") {
                return `${produceString(xmlObject[key], references)} `
            } else if (key == "#text") {
                return xmlObject[key]
            } else if (key == "section") {
                return `\n${produceString(xmlObject[key], references, level+1)}`
            } else if (key == "i") {
                return ` *${produceString(xmlObject[key], references)}*${appendOptionalSpace(nextObject)}`
            } else if (key == "p") {
                return `\n${produceString(xmlObject[key], references)}\n`
            } else if (key == ":@") {
                return `${produceString(xmlObject[key], references)}`
            } else if (key == "exlink") {
                const chapterNumber = xmlObject[":@"]["@_href"].split(":").at(-1).slice(-2)
                return ` [${Number(chapterNumber)}](exlink://${xmlObject[":@"]["@_href"]})${appendOptionalSpace(nextObject)}`
            } else if (key == "url") {
                return ` [${produceString(xmlObject["url"], references)}][${xmlObject[":@"]["@_href"]}] `
            } else if (key == "link") {
                return ` [${xmlObject[":@"]["@_href"]}](link://${xmlObject[":@"]["@_href"]})${appendOptionalSpace(nextObject)}`
            } else if (key == "note") {
                const footnote = `\n[^${xmlObject[":@"]['@_xml:id']}]: ${produceString(xmlObject[key], references)}\n`
                references.push(footnote)
                return `[^${xmlObject[":@"]['@_xml:id']}]${appendOptionalSpace(nextObject)}`
            } else if (key == "figure") {
                const image = xmlObject[key].find(o => o.mediaResource)
                const caption = xmlObject[key].find(o => o.caption)

                if (caption) {
                    return `\n${produceString(image, references)}\n<figure>\n${produceString(caption)}\n</figure>\n`
                } else {
                    return `\n${produceString(image, references)}\n`
                }
            } else if (key == "mediaResource") {
                return `![](${xmlObject[":@"]["@_href"]})`
            } else if (key == "caption") {
                return `<figcaption>${produceString(xmlObject[key], references)}</figcaption>`
            } 
            return ""
        }).join("")
    }
}

const btcRootDir = "/home/sigidli/Documents/business/exonumia/bitcoin-standard/9781119473862"
const excludeRootContent = [
    "pdf",
    "Manifest",
    "metadata",
    "cover_US",
    "control",
    "summary.xls",
    "protocol.html",
    // "fmatter",
    // "bmatter"
]
const rootDirectories = fs.readdirSync(btcRootDir).filter(d => !excludeRootContent.includes(d)) // .filter(d => d == "ch03")

rootDirectories.forEach(directory => {
    console.log(directory)
    const contentDirectories = fs.readdirSync(path.join(btcRootDir, directory))

    // TODO: image export
    const textFiles = fs.readdirSync(path.join(btcRootDir, `${directory}/text_s`))

    textFiles.forEach(file => {
        const fileContent = fs.readFileSync(path.join(btcRootDir, `${directory}/text_s/${file}`))
        const fileStringContent = fileContent.toString().split("\n").slice(6).join("\n")

        const parser = new XMLParser({
            ignoreAttributes: false,
            preserveOrder: true,
        });
            
        let xmlObject = parser.parse(fileStringContent)
        const references = []
        var markdownContent = produceString(xmlObject, references)
        markdownContent += references.join("")

        const resultDIR = "result"
        if (!fs.existsSync(resultDIR)) {
            fs.mkdirSync(resultDIR)
        }
        
        fs.writeFileSync(
            path.join(resultDIR, `${file}.md`),
            markdownContent
        )
    })
});