implement query

1 files changed, 109 insertions, 0 deletions

diff --git a/main.go b/main.go
new file mode 100644
index 0000000..8e3243d
--- /dev/null
+++ b/main.go
@@ -0,0 +1,109 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/PuerkitoBio/goquery"
+	"golang.org/x/net/html"
+)
+
+type Mode string
+
+const (
+	ModeQuery   Mode = "query"
+	ModeReplace Mode = "replace"
+	ModeAppend  Mode = "append"
+	ModePrepend Mode = "prepend"
+	ModeInvalid Mode = "invalid"
+
+	FilenameStdin string = "-"
+)
+
+func main() {
+	selector := flag.String("selector", "", "DOM query")
+	mode := flag.String("mode", "query", "Operation mode: query, replace, append, prepend")
+	filename := flag.String("filename", "", "Path to HTML file")
+	flag.Parse()
+
+	//args := flag.Args()
+
+	parsedMode, err := parseMode(*mode)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "failed to parse -mode: %s", err.Error())
+		os.Exit(1)
+	}
+
+	doc, err := parseFilename(*filename)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "failed to parse -filename: %s", err.Error())
+		os.Exit(1)
+	}
+
+	switch parsedMode {
+	case ModeQuery:
+		if *selector == "" {
+			// if selector is not specified return whole doc by default
+			htmlStr, err := doc.Html()
+			if err != nil {
+				fmt.Fprintf(os.Stderr, "failed to construct HTML string: %s", err.Error())
+				os.Exit(1)
+			}
+			fmt.Println(htmlStr)
+		} else {
+			doc.Find(*selector).Each(func(i int, s *goquery.Selection) {
+				var buf strings.Builder
+				err := html.Render(&buf, s.Get(0))
+				if err != nil {
+					fmt.Fprintf(os.Stderr, "failed to render node: %s", err.Error())
+					os.Exit(1)
+				}
+
+				output := buf.String()
+				fmt.Println(output)
+			})
+		}
+	case ModeReplace:
+	case ModeAppend:
+	case ModePrepend:
+	}
+}
+
+func parseMode(mode string) (Mode, error) {
+	validModes := map[string]any{
+		string(ModeQuery):   nil,
+		string(ModeReplace): nil,
+		string(ModeAppend):  nil,
+		string(ModePrepend): nil,
+	}
+
+	if _, ok := validModes[mode]; !ok {
+		return ModeInvalid, fmt.Errorf("invalid mode: %s", mode)
+	}
+
+	return Mode(mode), nil
+}
+
+func parseFilename(fileName string) (*goquery.Document, error) {
+	var fd *os.File
+	var err error
+
+	if fileName == FilenameStdin {
+		fd = os.Stdin
+	} else {
+		fd, err = os.Open(fileName)
+		if err != nil {
+			return nil, fmt.Errorf("error opening file: %s", err.Error())
+		}
+		defer fd.Close()
+	}
+
+	doc, err := goquery.NewDocumentFromReader(fd)
+	if err != nil {
+		return nil, fmt.Errorf("error parsing HTML: %s", err.Error())
+	}
+
+	return doc, nil
+}