'strict'
import { file } from 'bun'
import * as fs from 'fs'
import * as path from 'path'


let paths: string[] = []
let options = []

const defaultColors = {
    di: [1, 34],
    ln: [1, 36],
    ex: [1, 32]
}

for(const arg of process.argv.slice(3)){
    if(arg.startsWith('--')){
        options.push(arg)
    }
    else if(arg.startsWith('-')){
        for(let option of arg.slice(1)){
            options.push('-' + option);
        }
    }
    else{
        paths.push(arg)
    }
}

if(paths.length == 0){
    paths = [ process.cwd() ];
}


try{

    listFiles(paths[0], options)
}
catch(e){
    switch(e.code){
        case 'ENOENT':
            console.error(`path '${paths[0]}' does not exist`);
            break;
        default:
            console.error(`ls: ${e}`)
    }
}




function listFiles(directory: string, options: string[]){
    if(!fs.existsSync(directory)) {
        console.error('Path not found')
        return;
    }


    let files = ['.', '..', ...fs.readdirSync(paths[0])]

    if(!options.includes('-a')) {
        files = files.filter(file => !file.startsWith('.') || file === '.' || file === '..')
    }

    let colorList: typeof defaultColors

    if(process.env.ls_color) {
        colorList = { ...defaultColors, ...JSON.parse(process.env.ls_color)}
    } else {
        colorList = defaultColors
    }

    if(options.includes('-l')){
        console.log(`total ${file.length}`)
        for(let file of files){
            let result = ''
            const stats = fs.lstatSync(path.join(directory, file));
            let color = ''
            let defaultColor = '\x1b[0m'
            let fileType = '?'
            if(stats.isFile()){
                fileType = '-';
                if(stats.mode & 0o100){ //owner can execute
                    color = colorList.ex ? `\x1b[${colorList.ex[0]}m\x1b[${colorList.ex[1]}m` : '\x1b[0m'
                }
            }
            else if (stats.isDirectory()) {
                fileType = 'd';
                color = colorList.di ? `\x1b[${colorList.di[0]}m\x1b[${colorList.di[1]}m` : '\x1b[0m'
            }
            else if (stats.isSymbolicLink()){
                fileType = 'l'
                color = colorList.ln ? `\x1b[${colorList.ln[0]}m\x1b[${colorList.ln[1]}m` : '\x1b[0m'
            }
            result += fileType;
            const permissions = 'xwr'
            for(let i=8;i>=0;i--){
                result += parseInt(Math.pow(2,i).toString(2)) & stats.mode ?  permissions[i%3] : '-'
            }
            if(0o1000 & stats.mode){ // check sticky bit
                color = '\x1b[40m\x1b[92m\x1b[7m'
            }
            const date = stats.mtime.toDateString().split(' ');
            result += ` ${usernameFromUID(stats.uid)}\t${groupnameFromGID(stats.gid)}\t${stats.size}\t${date[2]} ${date[1]}. ${options.includes('--color') ? color : ''}${file}${defaultColor}`
            console.log(result)
        }
    }
    else{
        const defaultColor = '\x1b[0m';
        if(options.includes('--color')){
            let result = ''
            for(let file of files){
                const stats = fs.lstatSync(path.join(directory, file));
                let color = defaultColor
                if(0o1000 & stats.mode){ // check sticky bit
                    color = '\x1b[40m\x1b[92m\x1b[7m'
                } else if(stats.isDirectory()){
                    color = colorList.di ? `\x1b[${colorList.di[1]}m\x1b[${colorList.di[0]}m` : defaultColor
                } else if (stats.isSymbolicLink()){
                    color = colorList.ln ? `\x1b[${colorList.ln[1]}m\x1b[${colorList.ln[0]}m` : defaultColor
                }

                result += color + file + '  ' + defaultColor;
            }
            console.log(result)
        }else{
            console.log(files.join('  '))
        }
    }
}

function usernameFromUID(uid: string | number){
    if(uid == 0) return 'root'
    if(uid != 0) return 'unknown user'
    //TODO: add support for multiple users to the os
    return uid
}

function groupnameFromGID(uid: string | number){
    if(uid == 0) return 'root'
    if(uid != 0) return 'unknown group'
    //TODO: add support for multiple groups to the os
    return uid
}