Add CreatePost

postbuilder.go

@@ -0,0 +1,228 @@
+package blueskyclient
+
+import (
+	"errors"
+	"fmt"
+	"net/url"
+	"strings"
+	"time"
+
+	appbsky "github.com/bluesky-social/indigo/api/bsky"
+	lexutil "github.com/bluesky-social/indigo/lex/util"
+)
+
+var FeedPost_Embed appbsky.FeedPost_Embed
+
+type Facet_Type int
+
+const (
+	Facet_Link Facet_Type = iota + 1
+	Facet_Mention
+	Facet_Tag
+)
+
+// construct the post
+type PostBuilder struct {
+	Text  string
+	Facet []PostFacet
+	Embed PostEmbed
+}
+
+type PostFacet struct {
+	Ftype   Facet_Type
+	Value   string
+	T_facet string
+}
+
+type PostEmbed struct {
+	Link           PostLink
+	Images         []PostImage
+	UploadedImages []lexutil.LexBlob
+}
+
+type PostLink struct {
+	Title       string
+	Uri         url.URL
+	Description string
+	Thumb       lexutil.LexBlob
+}
+
+type PostImage struct {
+	Title string
+	Uri   url.URL
+}
+
+// Create a simple post with text
+func NewPostBuilder(text string) PostBuilder {
+	return PostBuilder{
+		Text:  text,
+		Facet: []PostFacet{},
+	}
+}
+
+// Create a Richtext Post with facests
+func (pb PostBuilder) WithFacet(ftype Facet_Type, value string, text string) PostBuilder {
+
+	pb.Facet = append(pb.Facet, PostFacet{
+		Ftype:   ftype,
+		Value:   value,
+		T_facet: text,
+	})
+
+	return pb
+}
+
+// Create a Post with external links
+func (pb PostBuilder) WithExternalLink(title string, link url.URL, description string, thumb lexutil.LexBlob) PostBuilder {
+
+	pb.Embed.Link.Title = title
+	pb.Embed.Link.Uri = link
+	pb.Embed.Link.Description = description
+	pb.Embed.Link.Thumb = thumb
+
+	return pb
+}
+
+// Create a Post with images
+func (pb PostBuilder) WithImages(blobs []lexutil.LexBlob, images []PostImage) PostBuilder {
+
+	pb.Embed.Images = images
+	pb.Embed.UploadedImages = blobs
+
+	return pb
+}
+
+// Build the request
+func (pb PostBuilder) Build() (appbsky.FeedPost, error) {
+
+	post := appbsky.FeedPost{}
+
+	post.Text = pb.Text
+	post.LexiconTypeID = "app.bsky.feed.post"
+	post.CreatedAt = time.Now().Format(time.RFC3339)
+
+	// RichtextFacet Section
+	// https://docs.bsky.app/docs/advanced-guides/post-richtext
+
+	Facets := []*appbsky.RichtextFacet{}
+
+	for _, f := range pb.Facet {
+		facet := &appbsky.RichtextFacet{}
+		features := []*appbsky.RichtextFacet_Features_Elem{}
+		feature := &appbsky.RichtextFacet_Features_Elem{}
+
+		switch f.Ftype {
+
+		case Facet_Link:
+			{
+				feature = &appbsky.RichtextFacet_Features_Elem{
+					RichtextFacet_Link: &appbsky.RichtextFacet_Link{
+						LexiconTypeID: f.Ftype.String(),
+						Uri:           f.Value,
+					},
+				}
+			}
+
+		case Facet_Mention:
+			{
+				feature = &appbsky.RichtextFacet_Features_Elem{
+					RichtextFacet_Mention: &appbsky.RichtextFacet_Mention{
+						LexiconTypeID: f.Ftype.String(),
+						Did:           f.Value,
+					},
+				}
+			}
+
+		case Facet_Tag:
+			{
+				feature = &appbsky.RichtextFacet_Features_Elem{
+					RichtextFacet_Tag: &appbsky.RichtextFacet_Tag{
+						LexiconTypeID: f.Ftype.String(),
+						Tag:           f.Value,
+					},
+				}
+			}
+
+		}
+
+		features = append(features, feature)
+		facet.Features = features
+
+		ByteStart, ByteEnd, err := findSubstring(post.Text, f.T_facet)
+		if err != nil {
+			return post, fmt.Errorf("unable to find the substring: %v , %v", f.T_facet, err)
+		}
+
+		index := &appbsky.RichtextFacet_ByteSlice{
+			ByteStart: int64(ByteStart),
+			ByteEnd:   int64(ByteEnd),
+		}
+		facet.Index = index
+
+		Facets = append(Facets, facet)
+	}
+
+	post.Facets = Facets
+
+	// Embed Section (either external links or images)
+	// As of now it allows only one Embed type per post:
+	// https://github.com/bluesky-social/indigo/blob/main/api/bsky/feedpost.go
+	if pb.Embed.Link != (PostLink{}) {
+
+		FeedPost_Embed.EmbedExternal = &appbsky.EmbedExternal{
+			LexiconTypeID: "app.bsky.embed.external",
+			External: &appbsky.EmbedExternal_External{
+				Title:       pb.Embed.Link.Title,
+				Uri:         pb.Embed.Link.Uri.String(),
+				Description: pb.Embed.Link.Description,
+				Thumb:       &pb.Embed.Link.Thumb,
+			},
+		}
+
+	} else {
+		if len(pb.Embed.Images) != 0 && len(pb.Embed.Images) == len(pb.Embed.UploadedImages) {
+
+			EmbedImages := appbsky.EmbedImages{
+				LexiconTypeID: "app.bsky.embed.images",
+				Images:        make([]*appbsky.EmbedImages_Image, len(pb.Embed.Images)),
+			}
+
+			for i, img := range pb.Embed.Images {
+				EmbedImages.Images[i] = &appbsky.EmbedImages_Image{
+					Alt:   img.Title,
+					Image: &pb.Embed.UploadedImages[i],
+				}
+			}
+
+			FeedPost_Embed.EmbedImages = &EmbedImages
+
+		}
+	}
+
+	// avoid error when trying to marshal empty field (*bsky.FeedPost_Embed)
+	if len(pb.Embed.Images) != 0 || pb.Embed.Link.Title != "" {
+		post.Embed = &FeedPost_Embed
+	}
+
+	return post, nil
+}
+
+func (f Facet_Type) String() string {
+	switch f {
+	case Facet_Link:
+		return "app.bsky.richtext.facet#link"
+	case Facet_Mention:
+		return "app.bsky.richtext.facet#mention"
+	case Facet_Tag:
+		return "app.bsky.richtext.facet#tag"
+	default:
+		return "Unknown"
+	}
+}
+func findSubstring(s, substr string) (int, int, error) {
+	index := strings.Index(s, substr)
+	if index == -1 {
+		return 0, 0, errors.New("substring not found")
+	}
+	return index, index + len(substr), nil
+}