gitlin/pages/gist.go

package pages

import (
	"bufio"
	"bytes"
	"codeberg.org/gothub/gothub/utils"
	"context"
	htmlfmt "github.com/alecthomas/chroma/v2/formatters/html"
	"github.com/alecthomas/chroma/v2/lexers"
	"github.com/alecthomas/chroma/v2/styles"
	"github.com/carlmjohnson/requests"
	"github.com/gocolly/colly"
	"github.com/gofiber/fiber/v2"
	"html/template"
	"log"
	"net/http"
	"os"
	"path/filepath"
	"strings"
)

type Gist struct {
	Fullname    string
	Refname     string
	Description string
	Revision    string
	Parent      string
	Stars       string
	Forks       string
}

type GistFiles struct {
	Name string
	File template.HTML
	Css  template.CSS
}

func HandleGist(c *fiber.Ctx) error {
	var gistArray []Gist
	var gistFilesArray []GistFiles

	resp, statusErr := http.Get("https://gists.github.com/" + c.Params("user") + "/" + c.Params("gistID"))
	if statusErr != nil {
		log.Println(statusErr)
	}
	if resp.StatusCode == 404 {
		// I need a better way to do this
		return c.Status(404).Render("error", fiber.Map{
			"title": "Error",
			"error": "Gist repository " + c.Params("user") + "/" + c.Params("gistID") + " not found",
		})
	}

	// Scraping
	Scrape := Gist{}

	UserAgent, ok := os.LookupEnv("GOTHUB_USER_AGENT")
	if !ok {
		UserAgent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.36"
	}

	sc := colly.NewCollector(colly.AllowedDomains("gist.github.com"), colly.UserAgent(UserAgent))

	sc.OnHTML("div.gisthead", func(e *colly.HTMLElement) {
		Scrape.Refname = c.Params("user") + "/" + c.Params("gistID")
		Scrape.Fullname = c.Params("user") + "/" + e.ChildText("a[href='/"+c.Params("user")+"/"+c.Params("gistID")+"' i]")
		dl := e.ChildAttr("a[href$='.zip']", "href")
		Scrape.Revision = dl[strings.LastIndex(dl, "/")+1 : len(dl)-len(".zip")]
		Scrape.Stars = e.ChildText("li a[href*='/" + c.Params("user") + "/" + c.Params("gistID") + "/stargazers' i]")
		Scrape.Parent = e.ChildText("span.note a")
		Scrape.Forks = e.ChildText("li span.social-count")
		// I need a better way to do this
		if Scrape.Forks == "" {
			Scrape.Forks = e.ChildText("li a[href*='/" + c.Params("user") + "/" + c.Params("gistID") + "/forks' i]")
		}
	})

	sc.OnHTML("div[itemprop='about']", func(e *colly.HTMLElement) {
		Scrape.Description = e.Text
	})

	sc.OnHTML("div.repository-content.gist-content", func(e *colly.HTMLElement) {
		e.ForEach("div.file-header", func(i int, el *colly.HTMLElement) {
			var file string
			url := "https://gist.github.com" + el.ChildAttr("div.file-actions a.Button", "href")
			err := requests.
				URL(url).
				ToString(&file).
				Fetch(context.Background())
			if err != nil {
				log.Println(err)
			}

			lexer := lexers.Match(el.ChildText("strong.user-select-contain.gist-blob-name.css-truncate-target"))
			if lexer == nil {
				lexer = lexers.Fallback
			}
			formatter := htmlfmt.New(
				htmlfmt.WithClasses(true),
				htmlfmt.ClassPrefix(strings.TrimPrefix(filepath.Ext(el.ChildText("strong.user-select-contain.gist-blob-name.css-truncate-target")), ".")),
				htmlfmt.WithLineNumbers(true),
				htmlfmt.PreventSurroundingPre(false),
			)
			buf := bytes.Buffer{}
			writer := bufio.NewWriter(&buf)
			style := styles.Get("native")

			tokens, err := lexer.Tokenise(nil, file)
			if err != nil {
				log.Println(err)
			}
			formatter.Format(writer, style, tokens)
			cssbuf := bytes.Buffer{}
			cssw := bufio.NewWriter(&cssbuf)
			formatter.WriteCSS(cssw, style)
			cssw.Flush()
			writer.Flush()

			fileFmt := template.HTML(buf.String())
			cssFmt := template.CSS(cssbuf.String())

			gistFilesArray = append(gistFilesArray, GistFiles{
				Name: el.ChildText("strong.user-select-contain.gist-blob-name.css-truncate-target"),
				File: fileFmt,
				Css:  cssFmt,
			})
		})
	})

	sc.Visit("https://gist.github.com/" + c.Params("user") + "/" + c.Params("gistID") + "/")
	// Add scrape-based info to gistArray
	gistArray = append(gistArray, Scrape)

	return c.Render("gist", fiber.Map{
		"title":  "Repository " + c.Params("user") + "/" + c.Params("gistID"),
		"branch": utils.Branch,
		"gist":   gistArray,
		"files":  gistFilesArray,
	})
}