import matter from 'gray-matter'
import path from 'path'
import fs from "fs"
import unified from "unified";
import markdown from "remark-parse";
import {wikiLinkPlugin} from "remark-wiki-link";
import html from "remark-html";
import frontmatter from "remark-frontmatter";
import externalLinks from "remark-external-links";
import highlight from "remark-highlight.js";

const postsDirectory = path.join(process.cwd(), 'posts')
const isFile = fileName => {
    return fs.lstatSync(fileName).isFile()
}

export const Transformer = {
    haveFrontMatter: function (content) {
        //console.log("\t Front matter data content", content)
        if (!content) return false
        var indexOfFirst = content.indexOf("---")
        //console.log("\t Front matter data firstIndex  ", indexOfFirst)
        //console.log("index first", indexOfFirst)
        if (indexOfFirst === -1) {
            return false
        }
        let indexOfSecond = content.indexOf("---", (indexOfFirst + 1));
        return indexOfSecond !== -1;

    },
    getFrontMatterData: function (filecontent) {
        if (Transformer.haveFrontMatter(filecontent)) {
            return matter(filecontent).data
        }
        return {}
    },

    getHtmlContent: function (content, {fileNames}) {
        let htmlContent = []
        let internalLinks = []
        const sanitizedContent = Transformer.preprocessThreeDashes(content)

        unified()
            .use(markdown, {gfm: true})
            .use(highlight)
            .use(externalLinks, {target: "_blank", rel: ['noopener']})
            .use(frontmatter, ['yaml', 'toml'])
            .use(wikiLinkPlugin, {
                permalinks:fileNames,
                pageResolver: function(pageName){
                    const name = [Transformer.parseFileNameFromPath(pageName)]
                    //console.log("\n\nwiki internal links", Transformer.parseFileNameFromPath(name[0]));

                    const backLink = {
                        title: name,
                        link: Transformer.parseFileNameFromPath(name[0]),
                        shortSummary: name
                    }

                    internalLinks.push(backLink);
                    return name
                },
                hrefTemplate: function(permalink){
                    permalink = Transformer.normalizeFileName(permalink)
                    permalink = permalink.replace("ç","c").replace("ı","i").replace("ş","s")
                    //console.log("wiki pemalink", permalink);
                    return `/note/${permalink}`
                },

                aliasDivider:"|"
            })
            .use(html)
            .process(sanitizedContent,
                function (err, file) {
                    //console.log("asd", String(file).slice(0,50))
                        //console.error("remark: ", report(err || file))
                        htmlContent.push(String(file).replace("\n", ""))
                    }
            )
        htmlContent =  htmlContent.join("")
        htmlContent = htmlContent.split("---")
        return [htmlContent, internalLinks]
    },

    // getReact : function (content, {fileNames}) {
    //     const sanitizedContent = Transformer.preprocessThreeDashes(content)
    //     let result = null
    //         Transformer.getProcessor(content, {fileNames})
    //         .use(rehypeReact, {createElement, Fragment})
    //         .process(sanitizedContent, file => {
    //             result = file.result
    //         })
    //
    //     return result
    // },

    /* SANITIZE MARKDOWN FOR --- */
    preprocessThreeDashes: function (content) {
        var indexOfFirst = content.indexOf("---")
        if (indexOfFirst === -1) {
            return content
        }
        var indexOfSecond = content.indexOf("---", (indexOfFirst + 1))
        const frontPart = content.slice(0, indexOfSecond);
        const contentPart = content.slice(indexOfSecond);
        const processedContent = contentPart.split("---").join("")
        //console.log("preprocess", indexOfFirst, indexOfSecond)
        //return frontPart.concat(processedContent)
        return processedContent
    },

    /* Normalize File Names */
    normalizeFileName: function (filename) {
        var processedFileName = filename.replace(".md", "")
        processedFileName = processedFileName.replace('(', '').replace(')', '')
        processedFileName = processedFileName.split(" ").join("-")
        // processedFileName = processedFileName.toLowerCase()
        const conversionLetters = [
            ["ç", "c"], ["ş", "s"], ["ı", "i"], ["ü", "u"], ["ö", "o"], ["ğ", "g"],
            ["Ç", "C"], ["Ş", "S"], ["İ", "I"], ["Ü", "U"], ["Ö", "O"], ["Ğ", "G"]

        ];
        conversionLetters.forEach(letterPair => {
                processedFileName = processedFileName.split(letterPair[0]).join(letterPair[1])
                //processedFileName = processedFileName.replace(letterPair[0], letterPair[1])
            }
        )
        //console.log("filename", processedFileName)
        return processedFileName
    },
    /* Parse file name from path then sanitize it */
    parseFileNameFromPath: function (filepath) {
        const parsedFileFromPath = filepath.split("/")[filepath.split("/").length - 1]
        const parsedFileName = parsedFileFromPath.replace(".md", "")
        return Transformer.normalizeFileName(parsedFileName)
    },

    /* Pair provided and existing Filenames*/
    pairCurrentFile: function (provided, ListOfFilePaths) {
        //console.log(provided, ListOfFilePaths)
        const providedSanitizedFileName = Transformer.normalizeFileName(provided);

        // Map file paths and return true if it pairs with provided
        const possibleFilePath = ListOfFilePaths.filter(possibleFilePath => {
            const possibleFileName = Transformer.parseFileNameFromPath(possibleFilePath);
            const possibleSanitizedFileName = Transformer.normalizeFileName(possibleFileName)
            //console.log("----", providedSanitizedFileName, possibleSanitizedFileName)

            //console.log("---", possibleSanitizedFileName, providedSanitizedFileName)
            return providedSanitizedFileName === possibleSanitizedFileName;

        })
        console.log("p---", possibleFilePath)
        return possibleFilePath[0]
    }
}