package progress

import (
	"fmt"
	"math"
	"regexp"
	"strconv"
	"strings"
	"sync"

	"golang.org/x/term"
)

var regex = regexp.MustCompile("\033\\[[0-9;]+m")

//║░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░░║ 40 characters

type ProgressInfo struct {
	Size          int64
	Desc          string
	ClearOnFinish bool
}

type ProgressBar struct {
	lock           sync.Mutex
	maxBytes       int64
	currentBytes   int64
	hasStarted     bool
	currentPercent int
	desc           string
	clearFinish    bool
	textWidth      int
}

func New(info ProgressInfo) *ProgressBar {
	return &ProgressBar{
		maxBytes:    info.Size,
		desc:        info.Desc,
		clearFinish: info.ClearOnFinish,
	}

}

func (p *ProgressBar) render(final bool) {

	p.lock.Lock()
	defer p.lock.Unlock()

	var sb strings.Builder

	numFilled := math.Round((float64(p.currentBytes) / float64(p.maxBytes)) * 40)
	numBlank := 40 - numFilled
	donePercent := math.Round(float64(p.currentBytes) / float64(p.maxBytes) * 100)

	if int(donePercent) == p.currentPercent {
		return
	}

	var blockColor string

	if final {
		blockColor = "34"
	} else {
		blockColor = "214"
	}

	sb.WriteString(p.desc)
	sb.WriteString("   ")

	percentString := strconv.Itoa(int(donePercent)) + "%"
	blankPercent := 4 - len(percentString)

	for i := 0; i < blankPercent; i++ {
		sb.WriteString(" ")
	}

	sb.WriteString(percentString)

	sb.WriteString("\033[1m\033[38;5;247m [\033[0m")

	for i := 0; i < int(numFilled); i++ {

		sb.WriteString(fmt.Sprintf("\033[38;5;%sm█\033[0m", blockColor))

	}

	if numFilled < 40 {

		numBlank = numBlank - 1

		sb.WriteString("\033[38;5;214m▒\033[0m")

		for i := 0; i < int(numBlank); i++ {
			sb.WriteString("\033[38;5;247m░\033[0m")
		}

	} else {

		for i := 0; i < int(numBlank); i++ {
			sb.WriteString("\033[38;5;247m░\033[0m")
		}

	}

	sb.WriteString("\033[1m\033[38;5;247m]\033[0m")

	width, _, err := term.GetSize(0)
	if err != nil {
		return
	}

	var lineNum int

	if width == 0 {
		lineNum = 1
	} else {
		lineNum = ((len(removeANSIEscapeCodes(sb.String())) + width - 1) / width)
	}

	if p.hasStarted {
		for i := 0; i < lineNum; i++ {
			if i == lineNum-1 {
				fmt.Println("\033[A\033[0G\033[K" + sb.String())
			} else {
				fmt.Println("\033[A\033[0G\033[K")
			}
		}
	} else {
		fmt.Println(sb.String())
		p.hasStarted = true
	}

	p.textWidth = len(removeANSIEscapeCodes(sb.String()))

}

func (p *ProgressBar) Add(num int64) {
	p.currentBytes = p.currentBytes + num

	p.render(false)
}

func (p *ProgressBar) Close() (err error) {

	if p.clearFinish {

		width, _, err := term.GetSize(0)
		if err != nil {
			return err
		}

		var lineNum int

		if width == 0 {
			lineNum = 1
		} else {
			lineNum = ((p.textWidth + width - 1) / width)
		}

		for i := 0; i < lineNum; i++ {
			fmt.Println("\033[A\033[0G\033[K")
		}

	} else {
		p.render(true)
	}

	return
}
func (p *ProgressBar) Write(b []byte) (n int, err error) {
	n = len(b)
	p.Add(int64(n))
	return
}

func (p *ProgressBar) Read(b []byte) (n int, err error) {
	p.Add(int64(n))
	return
}

func removeANSIEscapeCodes(input string) string {
	return regex.ReplaceAllString(input, "")
}