Implement preprocessing of post bodies for gemini

2 files changed, 41 insertions, 1 deletions

diff --git a/src/gmi/tpl.go b/src/gmi/tpl.go
index 7959b8e..7f41993 100644
--- a/src/gmi/tpl.go
+++ b/src/gmi/tpl.go
@@ -8,6 +8,7 @@ import (
 	"io"
 	"io/fs"
 	"net/url"
+	"path/filepath"
 	"strconv"
 	"strings"
 	"text/template"
@@ -83,6 +84,45 @@ func (r renderer) GetPostSeriesNextPrevious(p post.StoredPost) (rendererGetPostS
 	return res, nil
 }
 
+func (r renderer) PostBody(p post.StoredPost) (string, error) {
+
+	preprocessFuncs := post.PreprocessFunctions{
+		BlogURL: func(path string) string {
+			return filepath.Join("/", path)
+		},
+		AssetURL: func(id string) string {
+			return filepath.Join("/assets", id)
+		},
+		PostURL: func(id string) string {
+			return filepath.Join("/posts", id)
+		},
+		StaticURL: func(path string) string {
+			return filepath.Join("/static", path)
+		},
+		Image: func(args ...string) (string, error) {
+
+			var (
+				id    = args[0]
+				descr = "Image"
+			)
+
+			if len(args) > 1 {
+				descr = args[1]
+			}
+
+			return fmt.Sprintf("=> %s %s", filepath.Join("/assets", id), descr), nil
+		},
+	}
+
+	buf := new(bytes.Buffer)
+
+	if err := p.PreprocessBody(buf, preprocessFuncs); err != nil {
+		return "", fmt.Errorf("preprocessing post body: %w", err)
+	}
+
+	return buf.String(), nil
+}
+
 func (r renderer) GetQueryValue(key, def string) string {
 	v := r.url.Query().Get(key)
 	if v == "" {
diff --git a/src/gmi/tpl/posts/post.gmi b/src/gmi/tpl/posts/post.gmi
index 4f58c84..7d1719b 100644
--- a/src/gmi/tpl/posts/post.gmi
+++ b/src/gmi/tpl/posts/post.gmi
@@ -6,7 +6,7 @@
 > {{ $post.Description }}
 {{ end -}}
 
-{{ $post.Body }}
+{{ .PostBody $post }}
 
 --------------------------------------------------------------------------------