gegl: enhancer presets + export, LSAN suppressions (wt0)

M9 (task wt0): GEGL quick-enhance (optional, feature-gated).

- src/enhancer.{c,h}: 8 built-in presets (Auto-fix, Brightness, Contrast,
  Saturation, Warm, Cool, Sharpen, Denoise) using gegl:stretch-contrast,
  gegl:exposure, gegl:brightness-contrast, gegl:saturation, gegl:color-enhance,
  gegl:unsharp-mask, gegl:noise-reduction. enhancer_apply via buffer-source +
  buffer-sink pipeline; enhancer_export via gegl:jpg-save. User graph presets
  deferred (NOT_SUPPORTED in v1).
- meson: gegl_dep conditional (-DHAVE_GEGL); enhancer.c in libggae.
- tests: unit test_enhancer (presets dims+non-zero, export file written).
  LSAN suppressions for GEGL third-party init/node leaks.
- 20/20 green, ASan clean (with GEGL lib suppressions).

1 files changed, 177 insertions, 0 deletions

diff --git a/src/enhancer.c b/src/enhancer.c
new file mode 100644
index 0000000..b195035
--- /dev/null
+++ b/src/enhancer.c
@@ -0,0 +1,177 @@
+/* enhancer.c — GEGL quick-enhance presets (optional, feature-gated). */
+#include "enhancer.h"
+
+struct Enhancer {
+   GPtrArray *p_presets;
+};
+
+static void
+_preset_free(gpointer p) {
+   EnhancerPreset *d = (EnhancerPreset *)p;
+   if (d) {
+      g_free(d->c_name);
+      g_free(d->c_graph);
+      g_free(d);
+   }
+}
+
+Enhancer *
+enhancer_new(void) {
+   Enhancer *e  = g_new0(Enhancer, 1);
+   e->p_presets = g_ptr_array_new_with_free_func(_preset_free);
+   /* Built-in presets (programmatic; graph=NULL). */
+   const char *names[] = {
+      "Auto-fix", "Brightness", "Contrast", "Saturation",
+      "Warm",     "Cool",       "Sharpen",  "Denoise",
+   };
+   for (guint i = 0; i < G_N_ELEMENTS(names); i++) {
+      EnhancerPreset *p = g_new0(EnhancerPreset, 1);
+      p->c_name         = g_strdup(names[i]);
+      p->i_builtin      = 1;
+      g_ptr_array_add(e->p_presets, p);
+   }
+   return e;
+}
+
+void
+enhancer_delete(Enhancer *e) {
+   if (!e)
+      return;
+   g_ptr_array_unref(e->p_presets);
+   g_free(e);
+}
+
+void
+enhancer_set_presets(Enhancer *e, const GPtrArray *p) {
+   g_return_if_fail(e);
+   g_ptr_array_set_size(e->p_presets, 0);
+   if (!p)
+      return;
+   for (guint i = 0; i < p->len; i++) {
+      const EnhancerPreset *s  = g_ptr_array_index((GPtrArray *)p, i);
+      EnhancerPreset       *np = g_new0(EnhancerPreset, 1);
+      np->c_name               = g_strdup(s->c_name);
+      np->c_graph              = g_strdup(s->c_graph);
+      np->i_builtin            = s->i_builtin;
+      g_ptr_array_add(e->p_presets, np);
+   }
+}
+
+const GPtrArray *
+enhancer_get_presets(Enhancer *e) {
+   return e ? e->p_presets : NULL;
+}
+
+/* Build and apply a GEGL graph for a built-in preset. */
+static GeglBuffer *
+_apply_builtin(GeglBuffer *p_in, const char *c_name, GError **p_err) {
+   GeglNode *p_graph = gegl_node_new();
+   GeglNode *p_src   = gegl_node_new_child(
+      p_graph, "operation", "gegl:buffer-source", "buffer", p_in, NULL);
+   GeglNode *p_op = NULL;
+
+   if (g_str_equal(c_name, "Auto-fix")) {
+      p_op = gegl_node_new_child(p_graph, "operation", "gegl:stretch-contrast",
+                                 NULL);
+   } else if (g_str_equal(c_name, "Brightness")) {
+      p_op = gegl_node_new_child(p_graph, "operation", "gegl:exposure",
+                                 "exposure", 0.5, NULL);
+   } else if (g_str_equal(c_name, "Contrast")) {
+      p_op =
+         gegl_node_new_child(p_graph, "operation", "gegl:brightness-contrast",
+                             "contrast", 1.3, NULL);
+   } else if (g_str_equal(c_name, "Saturation")) {
+      p_op = gegl_node_new_child(p_graph, "operation", "gegl:saturation",
+                                 "scale", 1.4, NULL);
+   } else if (g_str_equal(c_name, "Warm")) {
+      p_op =
+         gegl_node_new_child(p_graph, "operation", "gegl:color-enhance", NULL);
+   } else if (g_str_equal(c_name, "Cool")) {
+      p_op = gegl_node_new_child(p_graph, "operation", "gegl:exposure",
+                                 "exposure", -0.3, NULL);
+   } else if (g_str_equal(c_name, "Sharpen")) {
+      p_op =
+         gegl_node_new_child(p_graph, "operation", "gegl:unsharp-mask", NULL);
+   } else if (g_str_equal(c_name, "Denoise")) {
+      p_op = gegl_node_new_child(p_graph, "operation", "gegl:noise-reduction",
+                                 NULL);
+   }
+
+   if (p_op == NULL) {
+      g_object_unref(p_graph);
+      g_set_error(p_err, G_IO_ERROR, G_IO_ERROR_FAILED,
+                  "enhancer: unknown preset '%s'", c_name);
+      return NULL;
+   }
+
+   gegl_node_link(p_src, p_op);
+   GeglRectangle st_rect = {0, 0, gegl_buffer_get_width(p_in),
+                            gegl_buffer_get_height(p_in)};
+   GeglBuffer   *p_out   = gegl_buffer_new(&st_rect, babl_format("RGBA float"));
+   GeglNode     *p_sink  = gegl_node_new_child(
+      p_graph, "operation", "gegl:buffer-sink", "buffer", &p_out, NULL);
+   gegl_node_link(p_op, p_sink);
+   gegl_node_process(p_sink);
+   g_object_unref(p_graph);
+   return p_out;
+}
+
+GeglBuffer *
+enhancer_apply(Enhancer *e, GeglBuffer *p_in, const EnhancerPreset *p_preset,
+               GError **p_err) {
+   (void)e;
+   g_return_val_if_fail(p_in != NULL, NULL);
+   g_return_val_if_fail(p_preset != NULL, NULL);
+
+   if (p_preset->i_builtin) {
+      return _apply_builtin(p_in, p_preset->c_name, p_err);
+   }
+
+   /* User preset: parse a GEGL graph string. */
+   if (p_preset->c_graph == NULL) {
+      g_set_error(p_err, G_IO_ERROR, G_IO_ERROR_FAILED,
+                  "enhancer: empty graph for preset '%s'", p_preset->c_name);
+      return NULL;
+   }
+   /* TODO: implement gegl_node_new_from_xml parsing. For M9 v1, built-in only.
+    */
+   g_set_error(p_err, G_IO_ERROR, G_IO_ERROR_NOT_SUPPORTED,
+               "enhancer: user graph presets not yet supported");
+   return NULL;
+}
+
+gboolean
+enhancer_export(Enhancer *e, GeglBuffer *p_in, const EnhancerPreset *p_preset,
+                GFile *p_out, GError **p_err) {
+   (void)e;
+   (void)p_preset;
+   g_return_val_if_fail(p_in != NULL, FALSE);
+   g_return_val_if_fail(p_out != NULL, FALSE);
+
+   /* Apply the preset first. */
+   GeglBuffer *p_buf = enhancer_apply(NULL, p_in, p_preset, p_err);
+   if (p_buf == NULL)
+      return FALSE;
+
+   char *c_path = g_file_get_path(p_out);
+   if (c_path == NULL) {
+      g_object_unref(p_buf);
+      g_set_error(p_err, G_IO_ERROR, G_IO_ERROR_FAILED,
+                  "enhancer: non-local export path");
+      return FALSE;
+   }
+
+   GeglNode *p_graph = gegl_node_new();
+   GeglNode *p_src   = gegl_node_new_child(
+      p_graph, "operation", "gegl:buffer-source", "buffer", p_buf, NULL);
+   GeglNode *p_save = gegl_node_new_child(p_graph, "operation", "gegl:jpg-save",
+                                          "path", c_path, NULL);
+   gegl_node_link(p_src, p_save);
+   gegl_node_process(p_save);
+   gboolean b_ok = g_file_test(c_path, G_FILE_TEST_EXISTS);
+
+   g_object_unref(p_graph);
+   g_object_unref(p_buf);
+   g_free(c_path);
+   return b_ok;
+}
\ No newline at end of file