import fs from 'fs'
import yargs from 'yargs/yargs'
import { hideBin } from 'yargs/helpers'
import { parse } from 'csv-parse/sync'

const argv = yargs(hideBin(process.argv)).command('Converter', 'Checks CSV for missig stuff, then converts CSV to Jiracula import file.', {})
.options({
    'file': {
        description: 'CSV file',
        alias: 'f',
        type: 'string',
        demandOption: true,
    },
    'month': {
        description: 'Month number to extract',
        alias: 'm',
        type: 'number',
        demandOption: true,
    }
}).help().version('1.0').argv

const colors = {
    red: "\x1b[31m",
    green: "\x1b[32m",
    yellow: "\x1b[33m",
    blue: "\x1b[34m",
    magenta: "\x1b[35m",
    cyan: "\x1b[36m",
    bold: "\x1b[1m"
}

// Regex patterns
const durationPattern = /(\d+(?:[.,]\d+)?)\s*(h|H)/
const codePattern = /(SMEIMKT[- ]?\d+)/

// Read CSV
if(!fs.existsSync(argv.file)) {
    console.error(`${colors.red}Cannot find this file !?`)
    process.exit(1)
}
const csv = fs.readFileSync(argv.file, 'utf8')
const records = parse(csv, {
    columns: false,
    skip_empty_lines: true
})


// Skip header
const [header, ...rows] = records

// Transform
let results = []

for(let row of rows) {
    if (row.length<3) continue
    
    const date = row[0]
    const tasksStr = row[2]
    if (!tasksStr) continue
    
    if(date.substring(3,5)!=String(argv.month).padStart(2, '0')) continue
    
    const tasks = tasksStr.split('+').map(t => t.trim())
    
    for (let t of tasks) {
        const durationMatch = durationPattern.exec(t)
        let duration = durationMatch ? durationMatch[1] : null
        
        const codeMatch = codePattern.exec(t)
        const code = codeMatch ? codeMatch[1].replace(' ', '-') : null
        
        results.push({
            Date: date.trim(),
            TaskCode: code,
            Duration: parseFloat(duration) || 0,
            Description: t
        })
    }
}

let errs=0, tot=0, timePerDate = {}
results.forEach(r => {
    if(!r.TaskCode){
        errs++
    } else if(!r.Duration){
        errs++
    } else {
        if(r.Date in timePerDate) timePerDate[r.Date] += r.Duration
        else timePerDate[r.Date] = r.Duration
    }
    console.log(
        `${colors.cyan}${r.Date} ` +
        `${(r.TaskCode) ? colors.yellow+r.TaskCode : colors.red+'Missing Code'} ` +
        `${(r.Duration) ? colors.yellow+r.Duration : colors.red+'Missing Duration'} ` +
        `${colors.green}${r.Description}`
    )
    tot++
})

if(errs>0){
    console.log(`\n${colors.red}${errs} parsing errors on ${tot} tasks.${colors.green}\n`)
} else {
    console.log(`\n${colors.green}${tot} task entries, no parsing errors.\n`)
}

const badDailyHours = {}
let billable = 0
for(let dat in timePerDate){
    if((timePerDate[dat] != 8) && (timePerDate[dat] != 4)) badDailyHours[dat] = timePerDate[dat]
    else billable += (timePerDate[dat]/8)
} 
if(Object.keys(badDailyHours).length>0){
    console.log(`${colors.red}Some dates don't have 8H...\n`)
    for(let dat in badDailyHours){
        console.log(`${colors.red} ${dat}: ${badDailyHours[dat]}H`)
    }
} else {
    console.log(`\n${colors.green}Ready to export to Jiracula !`)
    console.log(`Total billable days : ${billable}\n`)
    const outfile =  argv.file.substring(0, argv.file.lastIndexOf('.'))+'.jrcl.json'
    fs.writeFileSync(outfile, JSON.stringify(results, null, 2), 'utf8')
}