next button for tagged posts (#169)

No previous button because that would be annoying to implement serverside with pagination etc.

Closes #115

Fixed conflict with #154, #155, #156

Co-authored-by: video-prize-ranch <cb.8a3w5@simplelogin.co>
Reviewed-on: https://codeberg.org/rimgo/rimgo/pulls/169
Reviewed-by: video-prize-ranch <video-prize-ranch@noreply.codeberg.org>
Co-authored-by: orangix <orangix@noreply.codeberg.org>
Co-committed-by: orangix <orangix@noreply.codeberg.org>

pages/post.go

@@ -3,6 +3,7 @@ package pages
 import (
 	"crypto/rand"
 	"fmt"
+	"strconv"
 	"strings"
 
 	"codeberg.org/rimgo/rimgo/api"
@@ -10,6 +11,27 @@ import (
 	"github.com/gofiber/fiber/v2"
 )
 
+// Cursed function
+func nextInTag(client *api.Client, tagname, sort, page, I string) string {
+	i, err := strconv.Atoi(I)
+	if err != nil || i < 0 {
+		return ""
+	}
+	tag, err := client.FetchTag(tagname, sort, page)
+	if err != nil {
+		return ""
+	}
+	if i >= len(tag.Posts)-1 {
+		pageNumber, _ := strconv.Atoi(page)
+		tagn, err := client.FetchTag(tagname, sort, strconv.Itoa(pageNumber+1))
+		if err != nil {
+			return ""
+		}
+		return tagn.Posts[0].Link
+	}
+	return tag.Posts[i+1].Link
+}
+
 func HandlePost(c *fiber.Ctx) error {
 	utils.SetHeaders(c)
 	c.Set("X-Frame-Options", "DENY")
@@ -56,8 +78,16 @@ func HandlePost(c *fiber.Ctx) error {
 	}
 	c.Set("Content-Security-Policy", csp)
 
+	var next string
+	tagParam := strings.Split(c.Query("tag"), ".")
+	if len(tagParam) == 4 {
+		tag, sort, page, index := tagParam[0], tagParam[1], tagParam[2], tagParam[3]
+		next = nextInTag(ApiClient, tag, sort, page, index)
+	}
+
 	return c.Render("post", fiber.Map{
 		"post":     post,
+		"next":     next,
 		"comments": comments,
 		"nonce":    nonce,
 	})