// https://ftp.uniprot.org/pub/databases/uniprot/current_release/knowledgebase/taxonomic_divisions/uniprot_sprot_human.xml.gz

import fs from 'fs'
import readline from 'readline'
import { XMLParser } from 'fast-xml-parser'

const line$ = (path: string) => readline.createInterface({
    input: fs.createReadStream(path),
    crlfDelay: Infinity
})

const makeIndex = async (filePath: string, indexPath?: string) => {
    indexPath = indexPath || filePath + '.jsi'

    let byteAcc = 0
    const fromSel = new RegExp("^<entry")
    const toSel = new RegExp("^</entry>")
    const valSel = new RegExp('<accession>')
    let tmp =  {values:[]} as any
    for await (const line of line$(filePath)) {
        if(fromSel.test(line)) tmp['from'] = byteAcc

        byteAcc += (line.length + 1)

        if (valSel.test(line)) tmp['values'].push(line.match("<accession>(.*?)</accession>")![1]) // 'uck 

        if(toSel.test(line)) {
            await fs.promises.appendFile(indexPath, tmp.values.join(';') + '\t' + tmp.from + '\t' + byteAcc + '\n')
            tmp = {values:[]}
        }
    }
}

const readOffset = (path: string, from:number, to:number) => {
    return new Promise<string>(async (resolve, reject) => {
        const size = to - from
        const buffer = Buffer.alloc(size);
        let filehandle
        try {
            filehandle = await fs.promises.open(path, 'r+');
            await filehandle.read(buffer, 0, buffer.length, from);
        } finally {
            if (filehandle) {
                await filehandle.close()
                resolve(buffer.toString())
            }
        }
    })
}

const getEntryOffset = async (dbPath:string, accession:string): Promise<number[]> => {
    const indexPath = dbPath + '.jsi'
    if (!fs.existsSync(indexPath)) await makeIndex(dbPath)
    const lineSel = new RegExp(accession)
    for await (const line of line$(indexPath)) {
        if (lineSel.test(line)) return [Number(line.split('\t')[1]),Number(line.split('\t')[2])]
    }
    return [0, 0]
}

const getEntry = async (dbPath:string, accession:string) => {
    const parser = new XMLParser({
        ignoreAttributes: false, 
        alwaysCreateTextNode: false, 
        attributeNamePrefix: "",
        textNodeName: "value",
        allowBooleanAttributes: true,
    })

    const offsets = await getEntryOffset(dbPath, accession)
    return parser.parse(await readOffset(dbPath, offsets[0], offsets[1]))
}


const getEntryFromGeneName = async (idmappingPath: string, dbPath:string, geneName:string) => {
    const accessions = await getAccessFromGene(idmappingPath, geneName)
    return await getEntry(dbPath, accessions[0]) // seems to be always the first with entry
}


const getAccessFromGene = async (idmappingPath: string, geneName:string) => {
    const sel = new RegExp('Gene_Name\t' + geneName)
    let accessions: any[] = []
    for await (const line of line$(idmappingPath)) {
        if(sel.test(line)) accessions.push(line.split('\t')[0])
    }
    return accessions
}

const getInteractionsFromEntry = async (json:any) => {
    const blaskList = 
    ['DNA', 'PHOSPHOSERINE', 'MOTIFS', 'INFECTION', 'PROTEIN', 'PROTEINS', 'GAMMA-SECRETASE', 'CALCIUM',
    'MICROBIAL', 'VIRUS', 'HEPATITIS', 'HERPES', 'SIMPLEX', 'RELATED', 'AND', 'CLATHRIN', 'WORTMANNIN',
    'NUCLEOSOME', 'undefined']
    
    const uniprotIDs = Array.isArray(json.entry.accession) ? json.entry.accession : [json.entry.accession]

    // geneName
    const gnTT = Array.isArray(json.entry.gene) ? json.entry.gene[0] : json.entry.gene
    const gnT =  Array.isArray(gnTT.name) ? gnTT.name :  [gnTT.name]
    const geneName = gnT.filter((e:any)=> e.type === 'primary').map((e:any)=> e.value)[0]

    // Interactants
    const jecT = Array.isArray(json.entry.comment) ? json.entry.comment : [json.entry.comment]
    const interactants = jecT
    .filter((e:any)=> e?.type === 'interaction')
    .flatMap((e:any) => ({
        type         : 'interactant',
        fromProductId: e.interactant[0].id,
        toProductId  : e.interactant[1].id,
        to           : e.interactant[1].label,
        nExperiments : Number(e.experiments)
    }))

    const regExp = new RegExp('INTERACTION WITH |Interacts with |complex with ', 'i')
    const geneRegExp = new RegExp(/[A-Z]{1}[A-Z|0-9]{2,}$/)
    
    // uniprot_comment_text_value
    const commentInteractsWith = jecT
    .filter((e:any) => e?.text?.value)
    .filter((e:any) => regExp.test(e.text.value))
    .map((e:any) => ({
        to  : e.text.value
            .split(/\.|;/)
            .flatMap((ee:any) => ee.replace(/ *\([^)]*\) */g, ' '))
            .filter((ee:any) => regExp.test(ee))
            .flatMap((ee:any) => ee.trim().split(regExp))
            .flatMap((ee:any) => ee.split(/,| and | /))
            .filter((_:any) => _)
            .filter((ee:any) => geneRegExp.test(ee))
            .filter((ee:any) => !blaskList.includes(ee) && ee !== geneName)
            .map((ee:any) => ee.trim()),
        text: e.text.value,
        //evidences: e.text.evidence.split(' ')//.map((ee:string)=> json.entry.reference.filter((eee:any)=> eee.key === ee)) // Doesnt work with ref key
    }))
    .flatMap((e:any)=> e.to.flatMap((ee:any) => ({
        type    : 'uniprot_comment_text_value',
        to      : ee,
        text   : e.text
    })))

    // uniprot_reference_scope
    const referenceInteract = json.entry.reference
    .map((e:any)=> ({...e, scope : Array.isArray(e.scope) ? e.scope : [e.scope]}))
    .filter((e:any) => regExp.test(e.scope.join('')))
    .map((e:any)=> ({
        to: e.scope
            //.split(/\.|;/)
            .flatMap((ee:any) => regExp.test(ee) ? [ee] : [])
            .filter((_:any) => _)
            .flatMap((ee:any) => ee.replace(/ *\([^)]*\) */g, ' '))
            .filter((ee:any) => regExp.test(ee))
            .flatMap((ee:any) => ee.trim().split(regExp)[1])
            .flatMap((ee:any) => ee.split(/,| and | /i))
            .filter((_:any) => _)
            .filter((ee:any) => geneRegExp.test(ee))
            .filter((ee:any) => !blaskList.includes(ee) && ee !== geneName)
            .map((ee:any) => ee.trim()),
        ...e,
    }))
    .flatMap((e:any)=> e.to.flatMap((ee:any) => ({
        type    : 'reference_scope',
        to      : ee,
        scope   : e.scope, 
        //citation: e.citation
    })))

    // Group
    const byTo = {} as {[key:string]: any}
    [...interactants, ...referenceInteract, ...commentInteractsWith]
    //.map((e:any)=> byTo[e.to] = byTo[e.to] ? [e, ...byTo[e.to]] : [e] )
    .map((e:any)=> byTo[e.to] = byTo[e.to] ? {...e, ...byTo[e.to]} : {...e} )
    
    const results = Object.keys(byTo).map((e:any) => {
        delete byTo[e]?.to
        return {
            from: geneName,
            to: e,
            data: byTo[e]
        }
    })
    .filter((e:any) => !blaskList.includes(e.to) && e.to !== geneName)

    // await fs.promises.writeFile('test/tmp.json', JSON.stringify(results.map((e:any)=>e.to), null,4))
    
    return results
}

// const findDistance = async (idmappingPath: string, dbPath:string, geneNameA:string, geneNameB:string, maxDistance = 6) => {
//     let rounds = [[geneNameA]]

//     let tree = {[geneNameA]: {}} as {[key:string]:any}
//     let run = true

//     let a = tree
//     Object.keys(a).map((gene) => )

//     let nIter = 0
//     while(nIter <= maxDistance && run) {
//         for (const gA of rounds[nIter]) {
//             console.log(nIter,gA);
            
//             const tmp = await getInteractionsFromEntry(await getEntryFromGeneName(idmappingPath, dbPath, gA))
//             if (tmp.includes(geneNameB)) { run = false; break }
//             rounds.push(tmp)
//         }
//         nIter++
//     }

//     //console.log(rounds);
    
    
//     return nIter
// }

export { makeIndex, readOffset, getEntry as getEnrty, getEntryFromGeneName, getInteractionsFromEntry }