let spawn = require('child_process').spawn
let exec  = require('child_process').exec

function section(title) {
    let border = '-'.repeat(8 + title.length)
    let middle = '--- ' + title + ' ---'
    console.log()
    console.log()
    console.log()
    console.log(border)
    console.log(middle)
    console.log(border)
    console.log()
}

async function with_cwd(dir,fn) {
    let cwd = process.cwd()
    process.chdir(dir)
    let out = await fn()
    process.chdir(cwd)
    return out
}

function run(cmd,args) {
    let out = ''
    return new Promise((resolve, reject) => {
        console.log(`Calling '${cmd} ${args.join(' ')}'`)
        let proc = spawn(cmd,args,{stdio:'inherit', shell:true})
        proc.on('exit', (code) => {
            if (code) process.exit(code)
            resolve(out)
        })
    })
}

function run_read(cmd,args) {
    let out = ''
    return new Promise((resolve, reject) => {
        let proc = spawn(cmd,args,{shell:true})
        proc.stderr.pipe(process.stderr)
        proc.stdout.on('data', (data) => { out += data })
        proc.on('exit', (code) => {
            if (code) process.exit(code);
            resolve(out)
        })
    })
}

async function check_version (name,required,cfg) {
    if (!cfg) { cfg = {} }
    let version = await run_read(name,['--version'])
    version     = version.trim()
    if (cfg.preprocess) { version = cfg.preprocess(version) }
    if (cfg.silent !== true) {
        console.log(`Checking '${name}' version.`)
    }
    if (version != required) {
        throw `[ERROR] The '${name}' version '${version}' does not match the required one '${required}'.`
    }
}

module.exports = {section,run,run_read,check_version,with_cwd}