refactor api package comments

* use encoding/json for comment parsing

* refactor by moving loop code to an UnmarshalJSON

* use a preallocated array and indices to maintain order while using
  goroutines again, this was removed a while ago

* use new struct in comment.hbs and contextComment.hbs

* rewriteUrl partial to reduce rimgo-specific code in api

* move RenderError into pages package to avoid import cycle between render and utils

utils/error.go

@@ -1,43 +0,0 @@
-package utils
-
-import (
-	"fmt"
-	"io"
-	"net/http"
-	"strconv"
-
-	"codeberg.org/rimgo/rimgo/render"
-	"codeberg.org/rimgo/rimgo/static"
-)
-
-func RenderError(w http.ResponseWriter, r *http.Request, code int, str ...string) (err error) {
-	if len(str) != 1 {
-		str = []string{""}
-	}
-	codeStr := "generic"
-	if code == 0 {
-		code = 500
-	}
-	if code != 500 {
-		codeStr = strconv.Itoa(code)
-	}
-	if !Accepts(r, "text/html") && r.PathValue("extension") != "" {
-		w.Header().Set("Content-Type", "image/png")
-		w.WriteHeader(code)
-		file, _ := static.GetFiles().Open("img/error-" + codeStr + ".png")
-		defer file.Close()
-		_, err = io.Copy(w, file)
-
-	} else {
-		w.WriteHeader(code)
-		err = render.Render(w, "errors/"+codeStr, map[string]any{
-			"path": r.URL.Path,
-			"err":  str[0],
-		})
-	}
-	if err != nil {
-		// don't panic or return error, it will loop
-		fmt.Println("error in RenderError: " + err.Error())
-	}
-	return nil
-}

utils/request.go

@@ -1,6 +1,7 @@
 package utils
 
 import (
+	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
@@ -9,6 +10,42 @@ import (
 	"github.com/tidwall/gjson"
 )
 
+func GetJSONNew(url string) (json.RawMessage, error) {
+	req, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return json.RawMessage{}, err
+	}
+
+	SetReqHeaders(req)
+
+	client := http.Client{}
+	res, err := client.Do(req)
+	if err != nil {
+		return json.RawMessage{}, err
+	}
+	rateLimitRemaining := res.Header.Get("X-RateLimit-UserRemaining")
+	if rateLimitRemaining != "" {
+		ratelimit, _ := strconv.Atoi(rateLimitRemaining)
+		if ratelimit <= 0 {
+			return json.RawMessage{}, fmt.Errorf("ratelimited by imgur")
+		}
+	}
+
+	body, err := io.ReadAll(res.Body)
+	if err != nil {
+		return json.RawMessage{}, err
+	}
+
+	switch res.StatusCode {
+	case 200:
+		return body, nil
+	case 429:
+		return json.RawMessage{}, fmt.Errorf("ratelimited by imgur")
+	default:
+		return json.RawMessage{}, fmt.Errorf("received status %s, expected 200 OK.\n%s", res.Status, string(body))
+	}
+}
+
 func GetJSON(url string) (gjson.Result, error) {
 	req, err := http.NewRequest("GET", url, nil)
 	if err != nil {

utils/rewriteUrl.go

@@ -0,0 +1,25 @@
+package utils
+
+import (
+	"fmt"
+	"net/url"
+	"strings"
+)
+
+func RewriteUrl(link string) (string, error) {
+	url, err := url.Parse(link)
+	if err != nil {
+		return "", err
+	}
+	path := url.Path
+	if !strings.HasPrefix(path, "/") {
+		path = "/" + path
+	}
+	switch url.Host {
+	case "", "imgur.com", "www.imgur.com", "i.imgur.com":
+		return path, nil
+	case "i.stack.imgur.com":
+		return "/stack" + path, nil
+	}
+	return "", fmt.Errorf("unknown host %s", url.Host)
+}