upd

internal/rewrite/html.go

@@ -0,0 +1,124 @@
+package rewrite
+
+import (
+	"bytes"
+	"compress/flate"
+	"compress/gzip"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"regexp"
+	"strings"
+
+	"git.gulenok.ru/greenhaze/gaslight/internal/cheating"
+	"git.gulenok.ru/greenhaze/gaslight/internal/latex"
+	"git.gulenok.ru/greenhaze/gaslight/internal/openrouter"
+)
+
+var questionTestDivRe = regexp.MustCompile(`(?is)<div[^>]*\bid\s*=\s*["'][^"']*\bQuestionTest\b[^"']*["'][^>]*>`)
+
+type HTMLHook func(req *http.Request, html []byte) ([]byte, error)
+
+type Processor struct {
+	hook HTMLHook
+}
+
+func NewProcessor(hook HTMLHook) *Processor {
+	return &Processor{hook: hook}
+}
+
+func DefaultQuestionTestHook(_ *http.Request, html []byte) ([]byte, error) {
+	switch cheating.DetermineQuestionType(string(html)) {
+	case cheating.FullTextQuestion:
+		{
+
+			aiResponce, err := openrouter.AskOpenRouter(fmt.Sprintf("РЕШИ ЗАДАНИЕ И ДАЙ МАКСИМАЛЬНО КРАТКИЙ ОТВЕТ: %s", string(html)))
+			if err != nil {
+				log.Printf("openrouter failed %s", err)
+				return html, nil
+			}
+			return []byte(strings.ReplaceAll(string(html), "generated", latex.ConvertLaTeXToASCII(aiResponce))), nil
+		}
+	case cheating.QuestionWithPicture:
+		{
+		}
+	}
+
+	return []byte(strings.ReplaceAll(string(html), "generated", "pwned")), nil
+}
+
+func IsHTMLResponse(contentType string) bool {
+	contentType = strings.ToLower(contentType)
+	return strings.Contains(contentType, "text/html") || strings.Contains(contentType, "application/xhtml+xml")
+}
+
+func (p *Processor) RewriteIfNeeded(req *http.Request, contentEncoding string, body []byte) ([]byte, error) {
+	decoded, err := decodeBody(contentEncoding, body)
+	if err != nil {
+		return nil, err
+	}
+	if !questionTestDivRe.Match(decoded) {
+		return body, nil
+	}
+
+	modifiedDecoded, err := p.hook(req, decoded)
+	if err != nil {
+		return nil, err
+	}
+	return encodeBody(contentEncoding, modifiedDecoded)
+}
+
+func decodeBody(encoding string, body []byte) ([]byte, error) {
+	switch strings.ToLower(strings.TrimSpace(encoding)) {
+	case "", "identity":
+		return body, nil
+	case "gzip":
+		r, err := gzip.NewReader(bytes.NewReader(body))
+		if err != nil {
+			return nil, err
+		}
+		defer r.Close()
+		return io.ReadAll(r)
+	case "deflate":
+		r := flate.NewReader(bytes.NewReader(body))
+		defer r.Close()
+		return io.ReadAll(r)
+	default:
+		return nil, fmt.Errorf("unsupported content-encoding: %s", encoding)
+	}
+}
+
+func encodeBody(encoding string, decoded []byte) ([]byte, error) {
+	switch strings.ToLower(strings.TrimSpace(encoding)) {
+	case "", "identity":
+		return decoded, nil
+	case "gzip":
+		var buf bytes.Buffer
+		w := gzip.NewWriter(&buf)
+		if _, err := w.Write(decoded); err != nil {
+			_ = w.Close()
+			return nil, err
+		}
+		if err := w.Close(); err != nil {
+			return nil, err
+		}
+		return buf.Bytes(), nil
+	case "deflate":
+		var buf bytes.Buffer
+		w, err := flate.NewWriter(&buf, flate.DefaultCompression)
+		if err != nil {
+			return nil, err
+		}
+		if _, err := w.Write(decoded); err != nil {
+			_ = w.Close()
+			return nil, err
+		}
+		if err := w.Close(); err != nil {
+			return nil, err
+		}
+		return buf.Bytes(), nil
+	default:
+		return nil, fmt.Errorf("unsupported content-encoding: %s", encoding)
+	}
+}