utils.go

package utils

import (
	"errors"
	"fmt"
	"html"
	"regexp"
	"strconv"
	"strings"

	"github.com/gan-of-culture/get-sauce/config"
	"github.com/gan-of-culture/get-sauce/static"
)

// GetLastItemString of slice
func GetLastItemString(slice []string) string {
	if len(slice) <= 0 {
		return ""
	}
	return slice[len(slice)-1]
}

// CalcSizeInByte func
func CalcSizeInByte(number float64, unit string) int64 {
	switch unit {
	case "KB":
		number *= 1000
	case "MB":
		number *= 1000000
	case "GB":
		number *= 10000000000
	case "KiB":
		number *= 1024
	case "MiB":
		number *= 1048576
	case "GiB":
		number *= 1073741824
	}
	return int64(number)
}

// ByteCountSI turn bytes to SI (decimal) format - https://yourbasic.org/golang/formatting-byte-size-to-human-readable-format/
func ByteCountSI(b int64) string {
	const unit = 1000
	if b < unit {
		return fmt.Sprintf("%d B", b)
	}
	div, exp := int64(unit), 0
	for n := b / unit; n >= unit; n /= unit {
		div *= unit
		exp++
	}
	return fmt.Sprintf("%.1f %cB",
		float64(b)/float64(div), "kMGTPE"[exp])
}

// NeedDownloadList return the indices of gallery that need download
func NeedDownloadList(length int) []int {
	if config.Pages != "" {
		var items []int
		var selStart, selEnd int
		temp := strings.Split(config.Pages, ",")

		for _, i := range temp {
			selection := strings.Split(i, "-")
			selStart, _ = strconv.Atoi(strings.TrimSpace(selection[0]))

			if len(selection) >= 2 {
				selEnd, _ = strconv.Atoi(strings.TrimSpace(selection[1]))
			} else {
				selEnd = selStart
			}

			for item := selStart; item <= selEnd; item++ {
				items = append(items, item)
			}
		}
		return items
	}
	out := []int{}
	for i := 1; i <= length; i++ {
		out = append(out, i)
	}
	return out
}

// GetMediaType e.g. put in png get image, mp4 -> video
func GetMediaType(t string) static.DataType {
	switch t {
	case "jpg", "jpeg", "png", "gif", "webp", "avif":
		return static.DataTypeImage
	case "webm", "mp4", "mkv", "m4a", "txt", "m3u8", "avi":
		return static.DataTypeVideo
	default:
		return static.DataTypeUnknown
	}
}

// GetH1 of html - file idx -1 = last h1 found - if index out of range set to last h1
func GetH1(htmlString *string, idx int) string {
	return GetSectionHeadingElement(htmlString, 1, idx)
}

func GetSectionHeadingElement(htmlString *string, level, idx int) string {
	closingSectionHeadingTag := fmt.Sprintf("</h%d>", level)

	re := regexp.MustCompile(fmt.Sprintf(`[^>]*%s`, closingSectionHeadingTag))
	sectionHeadingElements := re.FindAllString(*htmlString, -1)

	sectionHeadingElementsLen := len(sectionHeadingElements)
	if idx == -1 {
		idx = sectionHeadingElementsLen
	}

	// if index out of range set last
	if sectionHeadingElementsLen < idx+1 {
		idx = sectionHeadingElementsLen - 1
		if idx == -1 {
			return ""
		}
	}
	return html.UnescapeString(strings.TrimSuffix(sectionHeadingElements[idx], closingSectionHeadingTag))
}

// GetMeta of HTML file
func GetMeta(htmlString *string, property string) string {
	re := regexp.MustCompile(fmt.Sprintf("<meta property=[\"']*%s[\"']* content=[\"']([^\"']*)", property))
	metaTags := re.FindAllStringSubmatch(*htmlString, -1)
	if len(metaTags) < 1 {
		return fmt.Sprintf("no matches found for %s", property)
	}
	return metaTags[0][1]
}

// RemoveAdjDuplicates of slice
func RemoveAdjDuplicates[T string | int](slice []T) []T {
	out := []T{}
	var last T
	for _, s := range slice {
		if s != last {
			out = append(out, s)
		}
		last = s
	}

	return out
}

// Wrap error with context
func Wrap(err error, ctx string) error {
	return errors.New(err.Error() + ": " + ctx)
}

// GetFileExt from simple string
func GetFileExt(str string) string {
	re := regexp.MustCompile(`\w+$`)
	return re.FindString(str)
}