Integrate online reverse image search

This makes use of our image processing capabilities in order to
turn arbitrary image files into normalized thumbnails,
upload them to a temporary host, and pass the resulting URI
to a search provider.

In future, fiv should ideally run the upload itself,
so that its status and any errors are obvious to the user,
as well as to get rid of the script's dependency on jq.

1 files changed, 43 insertions, 4 deletions

diff --git a/fiv.c b/fiv.c
index d58a5a5..3dfe058 100644
--- a/fiv.c
+++ b/fiv.c
@@ -1,7 +1,7 @@
 //
 // fiv.c: fuck-if-I-know-how-to-name-it image browser and viewer
 //
-// Copyright (c) 2021 - 2022, Přemysl Eric Janouch <p@janouch.name>
+// Copyright (c) 2021 - 2023, Přemysl Eric Janouch <p@janouch.name>
 //
 // Permission to use, copy, modify, and/or distribute this software for any
 // purpose with or without fee is hereby granted.
@@ -1934,8 +1934,8 @@ static const char stylesheet[] = "@define-color fiv-tile @content_view_bg; \
 	} \
 	.fiv-information label { padding: 0 4px; }";
 
-static void
-output_thumbnail(gchar **uris, gboolean extract, const char *size_arg)
+static FivThumbnailSize
+output_thumbnail_prologue(gchar **uris, const char *size_arg)
 {
 	if (!uris)
 		exit_fatal("No path given");
@@ -1956,6 +1956,38 @@ output_thumbnail(gchar **uris, gboolean extract, const char *size_arg)
 #ifdef G_OS_WIN32
 	_setmode(fileno(stdout), _O_BINARY);
 #endif
+	return size;
+}
+
+static void
+output_thumbnail_for_search(gchar **uris, const char *size_arg)
+{
+	FivThumbnailSize size = output_thumbnail_prologue(uris, size_arg);
+
+	GError *error = NULL;
+	GFile *file = g_file_new_for_uri(uris[0]);
+	cairo_surface_t *surface = NULL;
+	GBytes *bytes = NULL;
+	if ((surface = fiv_thumbnail_produce(file, size, &error)) &&
+		(bytes = fiv_io_serialize_for_search(surface, &error))) {
+		fwrite(
+			g_bytes_get_data(bytes, NULL), 1, g_bytes_get_size(bytes), stdout);
+		g_bytes_unref(bytes);
+	} else {
+		g_assert(error != NULL);
+	}
+
+	g_object_unref(file);
+	if (error)
+		exit_fatal("%s", error->message);
+
+	cairo_surface_destroy(surface);
+}
+
+static void
+output_thumbnail(gchar **uris, gboolean extract, const char *size_arg)
+{
+	FivThumbnailSize size = output_thumbnail_prologue(uris, size_arg);
 
 	GError *error = NULL;
 	GFile *file = g_file_new_for_uri(uris[0]);
@@ -1981,7 +2013,7 @@ main(int argc, char *argv[])
 {
 	gboolean show_version = FALSE, show_supported_media_types = FALSE,
 		invalidate_cache = FALSE, browse = FALSE, extract_thumbnail = FALSE;
-	gchar **args = NULL, *thumbnail_size = NULL;
+	gchar **args = NULL, *thumbnail_size = NULL, *thumbnail_size_search = NULL;
 	const GOptionEntry options[] = {
 		{G_OPTION_REMAINING, 0, 0, G_OPTION_ARG_FILENAME_ARRAY, &args,
 			NULL, "[PATH | URI]..."},
@@ -1991,6 +2023,9 @@ main(int argc, char *argv[])
 		{"browse", 0, G_OPTION_FLAG_IN_MAIN,
 			G_OPTION_ARG_NONE, &browse,
 			"Start in filesystem browsing mode", NULL},
+		{"thumbnail-for-search", 0, G_OPTION_FLAG_IN_MAIN,
+			G_OPTION_ARG_STRING, &thumbnail_size_search,
+			"Output an image file suitable for searching by content", "SIZE"},
 		{"extract-thumbnail", 0, G_OPTION_FLAG_IN_MAIN,
 			G_OPTION_ARG_NONE, &extract_thumbnail,
 			"Output any embedded thumbnail (superseding --thumbnail)", NULL},
@@ -2032,6 +2067,10 @@ main(int argc, char *argv[])
 		args[i] = g_file_get_uri(resolved);
 		g_object_unref(resolved);
 	}
+	if (thumbnail_size_search) {
+		output_thumbnail_for_search(args, thumbnail_size_search);
+		return 0;
+	}
 	if (extract_thumbnail || thumbnail_size) {
 		output_thumbnail(args, extract_thumbnail, thumbnail_size);
 		return 0;