Move FivIoModel to its own compilation unit

8 files changed, 604 insertions, 568 deletions

diff --git a/fiv-browser.h b/fiv-browser.h
index 0a93721..701cb50 100644
--- a/fiv-browser.h
+++ b/fiv-browser.h
@@ -17,7 +17,7 @@
 
 #pragma once
 
-#include "fiv-io.h"
+#include "fiv-io-model.h"
 
 #include <gtk/gtk.h>
 
diff --git a/fiv-io-model.c b/fiv-io-model.c
new file mode 100644
index 0000000..c133238
--- /dev/null
+++ b/fiv-io-model.c
@@ -0,0 +1,539 @@
+//
+// fiv-io-model.c: filesystem
+//
+// 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.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+//
+
+#include "fiv-io.h"
+#include "fiv-io-model.h"
+#include "xdg.h"
+
+static GPtrArray *
+model_entry_array_new(void)
+{
+	return g_ptr_array_new_with_free_func(g_rc_box_release);
+}
+
+struct _FivIoModel {
+	GObject parent_instance;
+	GPatternSpec **supported_patterns;
+
+	GFile *directory;                   ///< Currently loaded directory
+	GFileMonitor *monitor;              ///< "directory" monitoring
+	GPtrArray *subdirs;                 ///< "directory" contents
+	GPtrArray *files;                   ///< "directory" contents
+
+	FivIoModelSort sort_field;          ///< How to sort
+	gboolean sort_descending;           ///< Whether to sort in reverse
+	gboolean filtering;                 ///< Only show non-hidden, supported
+};
+
+G_DEFINE_TYPE(FivIoModel, fiv_io_model, G_TYPE_OBJECT)
+
+enum {
+	PROP_FILTERING = 1,
+	PROP_SORT_FIELD,
+	PROP_SORT_DESCENDING,
+	N_PROPERTIES
+};
+
+static GParamSpec *model_properties[N_PROPERTIES];
+
+enum {
+	FILES_CHANGED,
+	SUBDIRECTORIES_CHANGED,
+	LAST_SIGNAL,
+};
+
+// Globals are, sadly, the canonical way of storing signal numbers.
+static guint model_signals[LAST_SIGNAL];
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static gboolean
+model_supports(FivIoModel *self, const char *filename)
+{
+	gchar *utf8 = g_filename_to_utf8(filename, -1, NULL, NULL, NULL);
+	if (!utf8)
+		return FALSE;
+
+	gchar *lc = g_utf8_strdown(utf8, -1);
+	gsize lc_length = strlen(lc);
+	gchar *reversed = g_utf8_strreverse(lc, lc_length);
+	g_free(utf8);
+
+	// fnmatch() uses the /locale encoding/, and isn't present on Windows.
+	// TODO(p): Consider using g_file_info_get_display_name() for direct UTF-8.
+	gboolean result = FALSE;
+	for (GPatternSpec **p = self->supported_patterns; *p; p++)
+		if ((result = g_pattern_spec_match(*p, lc_length, lc, reversed)))
+			break;
+
+	g_free(lc);
+	g_free(reversed);
+	return result;
+}
+
+static inline int
+model_compare_entries(FivIoModel *self,
+	const FivIoModelEntry *entry1, GFile *file1,
+	const FivIoModelEntry *entry2, GFile *file2)
+{
+	if (g_file_has_prefix(file1, file2))
+		return +1;
+	if (g_file_has_prefix(file2, file1))
+		return -1;
+
+	int result = 0;
+	switch (self->sort_field) {
+	case FIV_IO_MODEL_SORT_MTIME:
+		result -= entry1->mtime_msec < entry2->mtime_msec;
+		result += entry1->mtime_msec > entry2->mtime_msec;
+		if (result != 0)
+			break;
+
+		// Fall-through
+	case FIV_IO_MODEL_SORT_NAME:
+	case FIV_IO_MODEL_SORT_COUNT:
+		result = strcmp(entry1->collate_key, entry2->collate_key);
+	}
+	return self->sort_descending ? -result : +result;
+}
+
+static gint
+model_compare(gconstpointer a, gconstpointer b, gpointer user_data)
+{
+	const FivIoModelEntry *entry1 = *(const FivIoModelEntry **) a;
+	const FivIoModelEntry *entry2 = *(const FivIoModelEntry **) b;
+	GFile *file1 = g_file_new_for_uri(entry1->uri);
+	GFile *file2 = g_file_new_for_uri(entry2->uri);
+	int result = model_compare_entries(user_data, entry1, file1, entry2, file2);
+	g_object_unref(file1);
+	g_object_unref(file2);
+	return result;
+}
+
+static size_t
+model_strsize(const char *string)
+{
+	if (!string)
+		return 0;
+
+	return strlen(string) + 1;
+}
+
+static char *
+model_strappend(char **p, const char *string, size_t size)
+{
+	if (!string)
+		return NULL;
+
+	char *destination = memcpy(*p, string, size);
+	*p += size;
+	return destination;
+}
+
+static FivIoModelEntry *
+model_entry_new(GFile *file, GFileInfo *info)
+{
+	gchar *uri = g_file_get_uri(file);
+	const gchar *target_uri = g_file_info_get_attribute_string(
+		info, G_FILE_ATTRIBUTE_STANDARD_TARGET_URI);
+	const gchar *display_name = g_file_info_get_display_name(info);
+
+	// TODO(p): Make it possible to use g_utf8_collate_key() instead,
+	// which does not use natural sorting.
+	gchar *parse_name = g_file_get_parse_name(file);
+	gchar *collate_key = g_utf8_collate_key_for_filename(parse_name, -1);
+	g_free(parse_name);
+
+	// The entries are immutable. Packing them into the structure
+	// should help memory usage as well as performance.
+	size_t size_uri          = model_strsize(uri);
+	size_t size_target_uri   = model_strsize(target_uri);
+	size_t size_display_name = model_strsize(display_name);
+	size_t size_collate_key  = model_strsize(collate_key);
+
+	FivIoModelEntry *entry = g_rc_box_alloc0(sizeof *entry +
+		size_uri +
+		size_target_uri +
+		size_display_name +
+		size_collate_key);
+
+	gchar *p = (gchar *) entry + sizeof *entry;
+	entry->uri          = model_strappend(&p, uri, size_uri);
+	entry->target_uri   = model_strappend(&p, target_uri, size_target_uri);
+	entry->display_name = model_strappend(&p, display_name, size_display_name);
+	entry->collate_key  = model_strappend(&p, collate_key, size_collate_key);
+
+	entry->filesize = (guint64) g_file_info_get_size(info);
+
+	GDateTime *mtime = g_file_info_get_modification_date_time(info);
+	if (mtime) {
+		entry->mtime_msec = g_date_time_to_unix(mtime) * 1000 +
+			g_date_time_get_microsecond(mtime) / 1000;
+		g_date_time_unref(mtime);
+	}
+
+	g_free(uri);
+	g_free(collate_key);
+	return entry;
+}
+
+static gboolean
+model_reload_to(FivIoModel *self, GFile *directory,
+	GPtrArray *subdirs, GPtrArray *files, GError **error)
+{
+	if (subdirs)
+		g_ptr_array_set_size(subdirs, 0);
+	if (files)
+		g_ptr_array_set_size(files, 0);
+
+	GFileEnumerator *enumerator = g_file_enumerate_children(directory,
+		G_FILE_ATTRIBUTE_STANDARD_TYPE ","
+		G_FILE_ATTRIBUTE_STANDARD_NAME ","
+		G_FILE_ATTRIBUTE_STANDARD_SIZE ","
+		G_FILE_ATTRIBUTE_STANDARD_DISPLAY_NAME ","
+		G_FILE_ATTRIBUTE_STANDARD_TARGET_URI ","
+		G_FILE_ATTRIBUTE_STANDARD_IS_HIDDEN ","
+		G_FILE_ATTRIBUTE_TIME_MODIFIED ","
+		G_FILE_ATTRIBUTE_TIME_MODIFIED_USEC,
+		G_FILE_QUERY_INFO_NONE, NULL, error);
+	if (!enumerator)
+		return FALSE;
+
+	GFileInfo *info = NULL;
+	GFile *child = NULL;
+	GError *e = NULL;
+	while (TRUE) {
+		if (!g_file_enumerator_iterate(enumerator, &info, &child, NULL, &e) &&
+			e) {
+			g_warning("%s", e->message);
+			g_clear_error(&e);
+			continue;
+		}
+		if (!info)
+			break;
+		if (self->filtering && g_file_info_get_is_hidden(info))
+			continue;
+
+		GPtrArray *target = NULL;
+		if (g_file_info_get_file_type(info) == G_FILE_TYPE_DIRECTORY)
+			target = subdirs;
+		else if (!self->filtering ||
+			model_supports(self, g_file_info_get_name(info)))
+			target = files;
+
+		if (target)
+			g_ptr_array_add(target, model_entry_new(child, info));
+	}
+	g_object_unref(enumerator);
+
+	if (subdirs)
+		g_ptr_array_sort_with_data(subdirs, model_compare, self);
+	if (files)
+		g_ptr_array_sort_with_data(files, model_compare, self);
+	return TRUE;
+}
+
+static gboolean
+model_reload(FivIoModel *self, GError **error)
+{
+	// Note that this will clear all entries on failure.
+	gboolean result = model_reload_to(
+		self, self->directory, self->subdirs, self->files, error);
+
+	g_signal_emit(self, model_signals[FILES_CHANGED], 0);
+	g_signal_emit(self, model_signals[SUBDIRECTORIES_CHANGED], 0);
+	return result;
+}
+
+static void
+model_resort(FivIoModel *self)
+{
+	g_ptr_array_sort_with_data(self->subdirs, model_compare, self);
+	g_ptr_array_sort_with_data(self->files, model_compare, self);
+
+	g_signal_emit(self, model_signals[FILES_CHANGED], 0);
+	g_signal_emit(self, model_signals[SUBDIRECTORIES_CHANGED], 0);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+// This would be more efficient iteratively, but it's not that important.
+static GFile *
+model_last_deep_subdirectory(FivIoModel *self, GFile *directory)
+{
+	GFile *result = NULL;
+	GPtrArray *subdirs = model_entry_array_new();
+	if (!model_reload_to(self, directory, subdirs, NULL, NULL))
+		goto out;
+
+	if (subdirs->len) {
+		FivIoModelEntry *entry = g_ptr_array_index(subdirs, subdirs->len - 1);
+		GFile *last = g_file_new_for_uri(entry->uri);
+		result = model_last_deep_subdirectory(self, last);
+		g_object_unref(last);
+	} else {
+		result = g_object_ref(directory);
+	}
+
+out:
+	g_ptr_array_free(subdirs, TRUE);
+	return result;
+}
+
+GFile *
+fiv_io_model_get_previous_directory(FivIoModel *self)
+{
+	g_return_val_if_fail(FIV_IS_IO_MODEL(self), NULL);
+
+	GFile *parent_directory = g_file_get_parent(self->directory);
+	if (!parent_directory)
+		return NULL;
+
+	GFile *result = NULL;
+	GPtrArray *subdirs = model_entry_array_new();
+	if (!model_reload_to(self, parent_directory, subdirs, NULL, NULL))
+		goto out;
+
+	for (gsize i = 0; i < subdirs->len; i++) {
+		FivIoModelEntry *entry = g_ptr_array_index(subdirs, i);
+		GFile *file = g_file_new_for_uri(entry->uri);
+		if (g_file_equal(file, self->directory)) {
+			g_object_unref(file);
+			break;
+		}
+
+		g_clear_object(&result);
+		result = file;
+	}
+	if (result) {
+		GFile *last = model_last_deep_subdirectory(self, result);
+		g_object_unref(result);
+		result = last;
+	} else {
+		result = g_object_ref(parent_directory);
+	}
+
+out:
+	g_object_unref(parent_directory);
+	g_ptr_array_free(subdirs, TRUE);
+	return result;
+}
+
+// This would be more efficient iteratively, but it's not that important.
+static GFile *
+model_next_directory_within_parents(FivIoModel *self, GFile *directory)
+{
+	GFile *parent_directory = g_file_get_parent(directory);
+	if (!parent_directory)
+		return NULL;
+
+	GFile *result = NULL;
+	GPtrArray *subdirs = model_entry_array_new();
+	if (!model_reload_to(self, parent_directory, subdirs, NULL, NULL))
+		goto out;
+
+	gboolean found_self = FALSE;
+	for (gsize i = 0; i < subdirs->len; i++) {
+		FivIoModelEntry *entry = g_ptr_array_index(subdirs, i);
+		result = g_file_new_for_uri(entry->uri);
+		if (found_self)
+			goto out;
+
+		found_self = g_file_equal(result, directory);
+		g_clear_object(&result);
+	}
+	if (!result)
+		result = model_next_directory_within_parents(self, parent_directory);
+
+out:
+	g_object_unref(parent_directory);
+	g_ptr_array_free(subdirs, TRUE);
+	return result;
+}
+
+GFile *
+fiv_io_model_get_next_directory(FivIoModel *self)
+{
+	g_return_val_if_fail(FIV_IS_IO_MODEL(self), NULL);
+
+	if (self->subdirs->len) {
+		FivIoModelEntry *entry = g_ptr_array_index(self->subdirs, 0);
+		return g_file_new_for_uri(entry->uri);
+	}
+
+	return model_next_directory_within_parents(self, self->directory);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static void
+fiv_io_model_finalize(GObject *gobject)
+{
+	FivIoModel *self = FIV_IO_MODEL(gobject);
+	for (GPatternSpec **p = self->supported_patterns; *p; p++)
+		g_pattern_spec_free(*p);
+	g_free(self->supported_patterns);
+
+	g_clear_object(&self->directory);
+	g_clear_object(&self->monitor);
+	g_ptr_array_free(self->subdirs, TRUE);
+	g_ptr_array_free(self->files, TRUE);
+
+	G_OBJECT_CLASS(fiv_io_model_parent_class)->finalize(gobject);
+}
+
+static void
+fiv_io_model_get_property(
+	GObject *object, guint property_id, GValue *value, GParamSpec *pspec)
+{
+	FivIoModel *self = FIV_IO_MODEL(object);
+	switch (property_id) {
+	case PROP_FILTERING:
+		g_value_set_boolean(value, self->filtering);
+		break;
+	case PROP_SORT_FIELD:
+		g_value_set_int(value, self->sort_field);
+		break;
+	case PROP_SORT_DESCENDING:
+		g_value_set_boolean(value, self->sort_descending);
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, pspec);
+	}
+}
+
+static void
+fiv_io_model_set_property(
+	GObject *object, guint property_id, const GValue *value, GParamSpec *pspec)
+{
+	FivIoModel *self = FIV_IO_MODEL(object);
+	switch (property_id) {
+	case PROP_FILTERING:
+		if (self->filtering != g_value_get_boolean(value)) {
+			self->filtering = !self->filtering;
+			g_object_notify_by_pspec(object, model_properties[property_id]);
+			(void) model_reload(self, NULL /* error */);
+		}
+		break;
+	case PROP_SORT_FIELD:
+		if ((int) self->sort_field != g_value_get_int(value)) {
+			self->sort_field = g_value_get_int(value);
+			g_object_notify_by_pspec(object, model_properties[property_id]);
+			model_resort(self);
+		}
+		break;
+	case PROP_SORT_DESCENDING:
+		if (self->sort_descending != g_value_get_boolean(value)) {
+			self->sort_descending = !self->sort_descending;
+			g_object_notify_by_pspec(object, model_properties[property_id]);
+			model_resort(self);
+		}
+		break;
+	default:
+		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, pspec);
+	}
+}
+
+static void
+fiv_io_model_class_init(FivIoModelClass *klass)
+{
+	GObjectClass *object_class = G_OBJECT_CLASS(klass);
+	object_class->get_property = fiv_io_model_get_property;
+	object_class->set_property = fiv_io_model_set_property;
+	object_class->finalize = fiv_io_model_finalize;
+
+	model_properties[PROP_FILTERING] = g_param_spec_boolean(
+		"filtering", "Filtering", "Only show non-hidden, supported entries",
+		TRUE, G_PARAM_READWRITE);
+	// TODO(p): GObject enumerations are annoying, but this should be one.
+	model_properties[PROP_SORT_FIELD] = g_param_spec_int(
+		"sort-field", "Sort field", "Sort order",
+		FIV_IO_MODEL_SORT_MIN, FIV_IO_MODEL_SORT_MAX,
+		FIV_IO_MODEL_SORT_NAME, G_PARAM_READWRITE);
+	model_properties[PROP_SORT_DESCENDING] = g_param_spec_boolean(
+		"sort-descending", "Sort descending", "Use reverse sort order",
+		FALSE, G_PARAM_READWRITE);
+	g_object_class_install_properties(
+		object_class, N_PROPERTIES, model_properties);
+
+	// TODO(p): Arguments something like: index, added, removed.
+	model_signals[FILES_CHANGED] =
+		g_signal_new("files-changed", G_TYPE_FROM_CLASS(klass), 0, 0,
+			NULL, NULL, NULL, G_TYPE_NONE, 0);
+	model_signals[SUBDIRECTORIES_CHANGED] =
+		g_signal_new("subdirectories-changed", G_TYPE_FROM_CLASS(klass), 0, 0,
+			NULL, NULL, NULL, G_TYPE_NONE, 0);
+}
+
+// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+
+static void
+fiv_io_model_init(FivIoModel *self)
+{
+	self->filtering = TRUE;
+
+	char **types = fiv_io_all_supported_media_types();
+	char **globs = extract_mime_globs((const char **) types);
+	g_strfreev(types);
+
+	gsize n = g_strv_length(globs);
+	self->supported_patterns =
+		g_malloc0_n(n + 1, sizeof *self->supported_patterns);
+	while (n--)
+		self->supported_patterns[n] = g_pattern_spec_new(globs[n]);
+	g_strfreev(globs);
+
+	self->files = model_entry_array_new();
+	self->subdirs = model_entry_array_new();
+}
+
+gboolean
+fiv_io_model_open(FivIoModel *self, GFile *directory, GError **error)
+{
+	g_return_val_if_fail(FIV_IS_IO_MODEL(self), FALSE);
+	g_return_val_if_fail(G_IS_FILE(directory), FALSE);
+
+	g_clear_object(&self->directory);
+	g_clear_object(&self->monitor);
+	self->directory = g_object_ref(directory);
+
+	// TODO(p): Process the ::changed signal.
+	self->monitor = g_file_monitor_directory(
+		directory, G_FILE_MONITOR_WATCH_MOVES, NULL, NULL /* error */);
+	return model_reload(self, error);
+}
+
+GFile *
+fiv_io_model_get_location(FivIoModel *self)
+{
+	g_return_val_if_fail(FIV_IS_IO_MODEL(self), NULL);
+	return self->directory;
+}
+
+FivIoModelEntry *const *
+fiv_io_model_get_files(FivIoModel *self, gsize *len)
+{
+	*len = self->files->len;
+	return (FivIoModelEntry *const *) self->files->pdata;
+}
+
+FivIoModelEntry *const *
+fiv_io_model_get_subdirs(FivIoModel *self, gsize *len)
+{
+	*len = self->subdirs->len;
+	return (FivIoModelEntry *const *) self->subdirs->pdata;
+}
diff --git a/fiv-io-model.h b/fiv-io-model.h
new file mode 100644
index 0000000..2fb9ad7
--- /dev/null
+++ b/fiv-io-model.h
@@ -0,0 +1,61 @@
+//
+// fiv-io-model.h: filesystem
+//
+// 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.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+//
+
+#pragma once
+
+#include <gio/gio.h>
+#include <glib.h>
+
+typedef enum _FivIoModelSort {
+	FIV_IO_MODEL_SORT_NAME,
+	FIV_IO_MODEL_SORT_MTIME,
+	FIV_IO_MODEL_SORT_COUNT,
+
+	FIV_IO_MODEL_SORT_MIN = 0,
+	FIV_IO_MODEL_SORT_MAX = FIV_IO_MODEL_SORT_COUNT - 1
+} FivIoModelSort;
+
+#define FIV_TYPE_IO_MODEL (fiv_io_model_get_type())
+G_DECLARE_FINAL_TYPE(FivIoModel, fiv_io_model, FIV, IO_MODEL, GObject)
+
+/// Loads a directory. Clears itself even on failure.
+gboolean fiv_io_model_open(FivIoModel *self, GFile *directory, GError **error);
+
+/// Returns the current location as a GFile.
+/// There is no ownership transfer, and the object may be NULL.
+GFile *fiv_io_model_get_location(FivIoModel *self);
+
+/// Returns the previous VFS directory in order, or NULL.
+GFile *fiv_io_model_get_previous_directory(FivIoModel *self);
+/// Returns the next VFS directory in order, or NULL.
+GFile *fiv_io_model_get_next_directory(FivIoModel *self);
+
+// These objects are reference-counted using GRcBox.
+typedef struct {
+	const char *uri;                    ///< GIO URI
+	const char *target_uri;             ///< GIO URI for any target
+	const char *display_name;           ///< Label for the file
+	const char *collate_key;            ///< Collate key for the filename
+	guint64 filesize;                   ///< Filesize in bytes
+	gint64 mtime_msec;                  ///< Modification time in milliseconds
+} FivIoModelEntry;
+
+#define fiv_io_model_entry_ref(e)    g_rc_box_acquire(e)
+#define fiv_io_model_entry_unref(e)  g_rc_box_release(e)
+
+FivIoModelEntry *const *fiv_io_model_get_files(FivIoModel *self, gsize *len);
+FivIoModelEntry *const *fiv_io_model_get_subdirs(FivIoModel *self, gsize *len);
diff --git a/fiv-io.c b/fiv-io.c
index 7ebf8ac..88e86ea 100644
--- a/fiv-io.c
+++ b/fiv-io.c
@@ -3449,529 +3449,6 @@ fiv_io_serialize_for_search(cairo_surface_t *surface, GError **error)
 		jpeg, length, (GDestroyNotify) tjFree, jpeg);
 }
 
-// --- Filesystem --------------------------------------------------------------
-
-#include "xdg.h"
-
-static GPtrArray *
-model_entry_array_new(void)
-{
-	return g_ptr_array_new_with_free_func(g_rc_box_release);
-}
-
-struct _FivIoModel {
-	GObject parent_instance;
-	GPatternSpec **supported_patterns;
-
-	GFile *directory;                   ///< Currently loaded directory
-	GFileMonitor *monitor;              ///< "directory" monitoring
-	GPtrArray *subdirs;                 ///< "directory" contents
-	GPtrArray *files;                   ///< "directory" contents
-
-	FivIoModelSort sort_field;          ///< How to sort
-	gboolean sort_descending;           ///< Whether to sort in reverse
-	gboolean filtering;                 ///< Only show non-hidden, supported
-};
-
-G_DEFINE_TYPE(FivIoModel, fiv_io_model, G_TYPE_OBJECT)
-
-enum {
-	PROP_FILTERING = 1,
-	PROP_SORT_FIELD,
-	PROP_SORT_DESCENDING,
-	N_PROPERTIES
-};
-
-static GParamSpec *model_properties[N_PROPERTIES];
-
-enum {
-	FILES_CHANGED,
-	SUBDIRECTORIES_CHANGED,
-	LAST_SIGNAL,
-};
-
-// Globals are, sadly, the canonical way of storing signal numbers.
-static guint model_signals[LAST_SIGNAL];
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-static gboolean
-model_supports(FivIoModel *self, const char *filename)
-{
-	gchar *utf8 = g_filename_to_utf8(filename, -1, NULL, NULL, NULL);
-	if (!utf8)
-		return FALSE;
-
-	gchar *lc = g_utf8_strdown(utf8, -1);
-	gsize lc_length = strlen(lc);
-	gchar *reversed = g_utf8_strreverse(lc, lc_length);
-	g_free(utf8);
-
-	// fnmatch() uses the /locale encoding/, and isn't present on Windows.
-	// TODO(p): Consider using g_file_info_get_display_name() for direct UTF-8.
-	gboolean result = FALSE;
-	for (GPatternSpec **p = self->supported_patterns; *p; p++)
-		if ((result = g_pattern_spec_match(*p, lc_length, lc, reversed)))
-			break;
-
-	g_free(lc);
-	g_free(reversed);
-	return result;
-}
-
-static inline int
-model_compare_entries(FivIoModel *self,
-	const FivIoModelEntry *entry1, GFile *file1,
-	const FivIoModelEntry *entry2, GFile *file2)
-{
-	if (g_file_has_prefix(file1, file2))
-		return +1;
-	if (g_file_has_prefix(file2, file1))
-		return -1;
-
-	int result = 0;
-	switch (self->sort_field) {
-	case FIV_IO_MODEL_SORT_MTIME:
-		result -= entry1->mtime_msec < entry2->mtime_msec;
-		result += entry1->mtime_msec > entry2->mtime_msec;
-		if (result != 0)
-			break;
-
-		// Fall-through
-	case FIV_IO_MODEL_SORT_NAME:
-	case FIV_IO_MODEL_SORT_COUNT:
-		result = strcmp(entry1->collate_key, entry2->collate_key);
-	}
-	return self->sort_descending ? -result : +result;
-}
-
-static gint
-model_compare(gconstpointer a, gconstpointer b, gpointer user_data)
-{
-	const FivIoModelEntry *entry1 = *(const FivIoModelEntry **) a;
-	const FivIoModelEntry *entry2 = *(const FivIoModelEntry **) b;
-	GFile *file1 = g_file_new_for_uri(entry1->uri);
-	GFile *file2 = g_file_new_for_uri(entry2->uri);
-	int result = model_compare_entries(user_data, entry1, file1, entry2, file2);
-	g_object_unref(file1);
-	g_object_unref(file2);
-	return result;
-}
-
-static size_t
-model_strsize(const char *string)
-{
-	if (!string)
-		return 0;
-
-	return strlen(string) + 1;
-}
-
-static char *
-model_strappend(char **p, const char *string, size_t size)
-{
-	if (!string)
-		return NULL;
-
-	char *destination = memcpy(*p, string, size);
-	*p += size;
-	return destination;
-}
-
-static FivIoModelEntry *
-model_entry_new(GFile *file, GFileInfo *info)
-{
-	gchar *uri = g_file_get_uri(file);
-	const gchar *target_uri = g_file_info_get_attribute_string(
-		info, G_FILE_ATTRIBUTE_STANDARD_TARGET_URI);
-	const gchar *display_name = g_file_info_get_display_name(info);
-
-	// TODO(p): Make it possible to use g_utf8_collate_key() instead,
-	// which does not use natural sorting.
-	gchar *parse_name = g_file_get_parse_name(file);
-	gchar *collate_key = g_utf8_collate_key_for_filename(parse_name, -1);
-	g_free(parse_name);
-
-	// The entries are immutable. Packing them into the structure
-	// should help memory usage as well as performance.
-	size_t size_uri          = model_strsize(uri);
-	size_t size_target_uri   = model_strsize(target_uri);
-	size_t size_display_name = model_strsize(display_name);
-	size_t size_collate_key  = model_strsize(collate_key);
-
-	FivIoModelEntry *entry = g_rc_box_alloc0(sizeof *entry +
-		size_uri +
-		size_target_uri +
-		size_display_name +
-		size_collate_key);
-
-	gchar *p = (gchar *) entry + sizeof *entry;
-	entry->uri          = model_strappend(&p, uri, size_uri);
-	entry->target_uri   = model_strappend(&p, target_uri, size_target_uri);
-	entry->display_name = model_strappend(&p, display_name, size_display_name);
-	entry->collate_key  = model_strappend(&p, collate_key, size_collate_key);
-
-	entry->filesize = (guint64) g_file_info_get_size(info);
-
-	GDateTime *mtime = g_file_info_get_modification_date_time(info);
-	if (mtime) {
-		entry->mtime_msec = g_date_time_to_unix(mtime) * 1000 +
-			g_date_time_get_microsecond(mtime) / 1000;
-		g_date_time_unref(mtime);
-	}
-
-	g_free(uri);
-	g_free(collate_key);
-	return entry;
-}
-
-static gboolean
-model_reload_to(FivIoModel *self, GFile *directory,
-	GPtrArray *subdirs, GPtrArray *files, GError **error)
-{
-	if (subdirs)
-		g_ptr_array_set_size(subdirs, 0);
-	if (files)
-		g_ptr_array_set_size(files, 0);
-
-	GFileEnumerator *enumerator = g_file_enumerate_children(directory,
-		G_FILE_ATTRIBUTE_STANDARD_TYPE ","
-		G_FILE_ATTRIBUTE_STANDARD_NAME ","
-		G_FILE_ATTRIBUTE_STANDARD_SIZE ","
-		G_FILE_ATTRIBUTE_STANDARD_DISPLAY_NAME ","
-		G_FILE_ATTRIBUTE_STANDARD_TARGET_URI ","
-		G_FILE_ATTRIBUTE_STANDARD_IS_HIDDEN ","
-		G_FILE_ATTRIBUTE_TIME_MODIFIED ","
-		G_FILE_ATTRIBUTE_TIME_MODIFIED_USEC,
-		G_FILE_QUERY_INFO_NONE, NULL, error);
-	if (!enumerator)
-		return FALSE;
-
-	GFileInfo *info = NULL;
-	GFile *child = NULL;
-	GError *e = NULL;
-	while (TRUE) {
-		if (!g_file_enumerator_iterate(enumerator, &info, &child, NULL, &e) &&
-			e) {
-			g_warning("%s", e->message);
-			g_clear_error(&e);
-			continue;
-		}
-		if (!info)
-			break;
-		if (self->filtering && g_file_info_get_is_hidden(info))
-			continue;
-
-		GPtrArray *target = NULL;
-		if (g_file_info_get_file_type(info) == G_FILE_TYPE_DIRECTORY)
-			target = subdirs;
-		else if (!self->filtering ||
-			model_supports(self, g_file_info_get_name(info)))
-			target = files;
-
-		if (target)
-			g_ptr_array_add(target, model_entry_new(child, info));
-	}
-	g_object_unref(enumerator);
-
-	if (subdirs)
-		g_ptr_array_sort_with_data(subdirs, model_compare, self);
-	if (files)
-		g_ptr_array_sort_with_data(files, model_compare, self);
-	return TRUE;
-}
-
-static gboolean
-model_reload(FivIoModel *self, GError **error)
-{
-	// Note that this will clear all entries on failure.
-	gboolean result = model_reload_to(
-		self, self->directory, self->subdirs, self->files, error);
-
-	g_signal_emit(self, model_signals[FILES_CHANGED], 0);
-	g_signal_emit(self, model_signals[SUBDIRECTORIES_CHANGED], 0);
-	return result;
-}
-
-static void
-model_resort(FivIoModel *self)
-{
-	g_ptr_array_sort_with_data(self->subdirs, model_compare, self);
-	g_ptr_array_sort_with_data(self->files, model_compare, self);
-
-	g_signal_emit(self, model_signals[FILES_CHANGED], 0);
-	g_signal_emit(self, model_signals[SUBDIRECTORIES_CHANGED], 0);
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-// This would be more efficient iteratively, but it's not that important.
-static GFile *
-model_last_deep_subdirectory(FivIoModel *self, GFile *directory)
-{
-	GFile *result = NULL;
-	GPtrArray *subdirs = model_entry_array_new();
-	if (!model_reload_to(self, directory, subdirs, NULL, NULL))
-		goto out;
-
-	if (subdirs->len) {
-		FivIoModelEntry *entry = g_ptr_array_index(subdirs, subdirs->len - 1);
-		GFile *last = g_file_new_for_uri(entry->uri);
-		result = model_last_deep_subdirectory(self, last);
-		g_object_unref(last);
-	} else {
-		result = g_object_ref(directory);
-	}
-
-out:
-	g_ptr_array_free(subdirs, TRUE);
-	return result;
-}
-
-GFile *
-fiv_io_model_get_previous_directory(FivIoModel *self)
-{
-	g_return_val_if_fail(FIV_IS_IO_MODEL(self), NULL);
-
-	GFile *parent_directory = g_file_get_parent(self->directory);
-	if (!parent_directory)
-		return NULL;
-
-	GFile *result = NULL;
-	GPtrArray *subdirs = model_entry_array_new();
-	if (!model_reload_to(self, parent_directory, subdirs, NULL, NULL))
-		goto out;
-
-	for (gsize i = 0; i < subdirs->len; i++) {
-		FivIoModelEntry *entry = g_ptr_array_index(subdirs, i);
-		GFile *file = g_file_new_for_uri(entry->uri);
-		if (g_file_equal(file, self->directory)) {
-			g_object_unref(file);
-			break;
-		}
-
-		g_clear_object(&result);
-		result = file;
-	}
-	if (result) {
-		GFile *last = model_last_deep_subdirectory(self, result);
-		g_object_unref(result);
-		result = last;
-	} else {
-		result = g_object_ref(parent_directory);
-	}
-
-out:
-	g_object_unref(parent_directory);
-	g_ptr_array_free(subdirs, TRUE);
-	return result;
-}
-
-// This would be more efficient iteratively, but it's not that important.
-static GFile *
-model_next_directory_within_parents(FivIoModel *self, GFile *directory)
-{
-	GFile *parent_directory = g_file_get_parent(directory);
-	if (!parent_directory)
-		return NULL;
-
-	GFile *result = NULL;
-	GPtrArray *subdirs = model_entry_array_new();
-	if (!model_reload_to(self, parent_directory, subdirs, NULL, NULL))
-		goto out;
-
-	gboolean found_self = FALSE;
-	for (gsize i = 0; i < subdirs->len; i++) {
-		FivIoModelEntry *entry = g_ptr_array_index(subdirs, i);
-		result = g_file_new_for_uri(entry->uri);
-		if (found_self)
-			goto out;
-
-		found_self = g_file_equal(result, directory);
-		g_clear_object(&result);
-	}
-	if (!result)
-		result = model_next_directory_within_parents(self, parent_directory);
-
-out:
-	g_object_unref(parent_directory);
-	g_ptr_array_free(subdirs, TRUE);
-	return result;
-}
-
-GFile *
-fiv_io_model_get_next_directory(FivIoModel *self)
-{
-	g_return_val_if_fail(FIV_IS_IO_MODEL(self), NULL);
-
-	if (self->subdirs->len) {
-		FivIoModelEntry *entry = g_ptr_array_index(self->subdirs, 0);
-		return g_file_new_for_uri(entry->uri);
-	}
-
-	return model_next_directory_within_parents(self, self->directory);
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-static void
-fiv_io_model_finalize(GObject *gobject)
-{
-	FivIoModel *self = FIV_IO_MODEL(gobject);
-	for (GPatternSpec **p = self->supported_patterns; *p; p++)
-		g_pattern_spec_free(*p);
-	g_free(self->supported_patterns);
-
-	g_clear_object(&self->directory);
-	g_clear_object(&self->monitor);
-	g_ptr_array_free(self->subdirs, TRUE);
-	g_ptr_array_free(self->files, TRUE);
-
-	G_OBJECT_CLASS(fiv_io_model_parent_class)->finalize(gobject);
-}
-
-static void
-fiv_io_model_get_property(
-	GObject *object, guint property_id, GValue *value, GParamSpec *pspec)
-{
-	FivIoModel *self = FIV_IO_MODEL(object);
-	switch (property_id) {
-	case PROP_FILTERING:
-		g_value_set_boolean(value, self->filtering);
-		break;
-	case PROP_SORT_FIELD:
-		g_value_set_int(value, self->sort_field);
-		break;
-	case PROP_SORT_DESCENDING:
-		g_value_set_boolean(value, self->sort_descending);
-		break;
-	default:
-		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, pspec);
-	}
-}
-
-static void
-fiv_io_model_set_property(
-	GObject *object, guint property_id, const GValue *value, GParamSpec *pspec)
-{
-	FivIoModel *self = FIV_IO_MODEL(object);
-	switch (property_id) {
-	case PROP_FILTERING:
-		if (self->filtering != g_value_get_boolean(value)) {
-			self->filtering = !self->filtering;
-			g_object_notify_by_pspec(object, model_properties[property_id]);
-			(void) model_reload(self, NULL /* error */);
-		}
-		break;
-	case PROP_SORT_FIELD:
-		if ((int) self->sort_field != g_value_get_int(value)) {
-			self->sort_field = g_value_get_int(value);
-			g_object_notify_by_pspec(object, model_properties[property_id]);
-			model_resort(self);
-		}
-		break;
-	case PROP_SORT_DESCENDING:
-		if (self->sort_descending != g_value_get_boolean(value)) {
-			self->sort_descending = !self->sort_descending;
-			g_object_notify_by_pspec(object, model_properties[property_id]);
-			model_resort(self);
-		}
-		break;
-	default:
-		G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, pspec);
-	}
-}
-
-static void
-fiv_io_model_class_init(FivIoModelClass *klass)
-{
-	GObjectClass *object_class = G_OBJECT_CLASS(klass);
-	object_class->get_property = fiv_io_model_get_property;
-	object_class->set_property = fiv_io_model_set_property;
-	object_class->finalize = fiv_io_model_finalize;
-
-	model_properties[PROP_FILTERING] = g_param_spec_boolean(
-		"filtering", "Filtering", "Only show non-hidden, supported entries",
-		TRUE, G_PARAM_READWRITE);
-	// TODO(p): GObject enumerations are annoying, but this should be one.
-	model_properties[PROP_SORT_FIELD] = g_param_spec_int(
-		"sort-field", "Sort field", "Sort order",
-		FIV_IO_MODEL_SORT_MIN, FIV_IO_MODEL_SORT_MAX,
-		FIV_IO_MODEL_SORT_NAME, G_PARAM_READWRITE);
-	model_properties[PROP_SORT_DESCENDING] = g_param_spec_boolean(
-		"sort-descending", "Sort descending", "Use reverse sort order",
-		FALSE, G_PARAM_READWRITE);
-	g_object_class_install_properties(
-		object_class, N_PROPERTIES, model_properties);
-
-	// TODO(p): Arguments something like: index, added, removed.
-	model_signals[FILES_CHANGED] =
-		g_signal_new("files-changed", G_TYPE_FROM_CLASS(klass), 0, 0,
-			NULL, NULL, NULL, G_TYPE_NONE, 0);
-	model_signals[SUBDIRECTORIES_CHANGED] =
-		g_signal_new("subdirectories-changed", G_TYPE_FROM_CLASS(klass), 0, 0,
-			NULL, NULL, NULL, G_TYPE_NONE, 0);
-}
-
-// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
-
-static void
-fiv_io_model_init(FivIoModel *self)
-{
-	self->filtering = TRUE;
-
-	char **types = fiv_io_all_supported_media_types();
-	char **globs = extract_mime_globs((const char **) types);
-	g_strfreev(types);
-
-	gsize n = g_strv_length(globs);
-	self->supported_patterns =
-		g_malloc0_n(n + 1, sizeof *self->supported_patterns);
-	while (n--)
-		self->supported_patterns[n] = g_pattern_spec_new(globs[n]);
-	g_strfreev(globs);
-
-	self->files = model_entry_array_new();
-	self->subdirs = model_entry_array_new();
-}
-
-gboolean
-fiv_io_model_open(FivIoModel *self, GFile *directory, GError **error)
-{
-	g_return_val_if_fail(FIV_IS_IO_MODEL(self), FALSE);
-	g_return_val_if_fail(G_IS_FILE(directory), FALSE);
-
-	g_clear_object(&self->directory);
-	g_clear_object(&self->monitor);
-	self->directory = g_object_ref(directory);
-
-	// TODO(p): Process the ::changed signal.
-	self->monitor = g_file_monitor_directory(
-		directory, G_FILE_MONITOR_WATCH_MOVES, NULL, NULL /* error */);
-	return model_reload(self, error);
-}
-
-GFile *
-fiv_io_model_get_location(FivIoModel *self)
-{
-	g_return_val_if_fail(FIV_IS_IO_MODEL(self), NULL);
-	return self->directory;
-}
-
-FivIoModelEntry *const *
-fiv_io_model_get_files(FivIoModel *self, gsize *len)
-{
-	*len = self->files->len;
-	return (FivIoModelEntry *const *) self->files->pdata;
-}
-
-FivIoModelEntry *const *
-fiv_io_model_get_subdirs(FivIoModel *self, gsize *len)
-{
-	*len = self->subdirs->len;
-	return (FivIoModelEntry *const *) self->subdirs->pdata;
-}
-
 // --- Export ------------------------------------------------------------------
 
 unsigned char *
diff --git a/fiv-io.h b/fiv-io.h
index 3f8c65b..121f136 100644
--- a/fiv-io.h
+++ b/fiv-io.h
@@ -109,48 +109,6 @@ cairo_surface_t *fiv_io_deserialize(GBytes *bytes, guint64 *user_data);
 
 GBytes *fiv_io_serialize_for_search(cairo_surface_t *surface, GError **error);
 
-// --- Filesystem --------------------------------------------------------------
-
-typedef enum _FivIoModelSort {
-	FIV_IO_MODEL_SORT_NAME,
-	FIV_IO_MODEL_SORT_MTIME,
-	FIV_IO_MODEL_SORT_COUNT,
-
-	FIV_IO_MODEL_SORT_MIN = 0,
-	FIV_IO_MODEL_SORT_MAX = FIV_IO_MODEL_SORT_COUNT - 1
-} FivIoModelSort;
-
-#define FIV_TYPE_IO_MODEL (fiv_io_model_get_type())
-G_DECLARE_FINAL_TYPE(FivIoModel, fiv_io_model, FIV, IO_MODEL, GObject)
-
-/// Loads a directory. Clears itself even on failure.
-gboolean fiv_io_model_open(FivIoModel *self, GFile *directory, GError **error);
-
-/// Returns the current location as a GFile.
-/// There is no ownership transfer, and the object may be NULL.
-GFile *fiv_io_model_get_location(FivIoModel *self);
-
-/// Returns the previous VFS directory in order, or NULL.
-GFile *fiv_io_model_get_previous_directory(FivIoModel *self);
-/// Returns the next VFS directory in order, or NULL.
-GFile *fiv_io_model_get_next_directory(FivIoModel *self);
-
-// These objects are reference-counted using GRcBox.
-typedef struct {
-	const char *uri;                    ///< GIO URI
-	const char *target_uri;             ///< GIO URI for any target
-	const char *display_name;           ///< Label for the file
-	const char *collate_key;            ///< Collate key for the filename
-	guint64 filesize;                   ///< Filesize in bytes
-	gint64 mtime_msec;                  ///< Modification time in milliseconds
-} FivIoModelEntry;
-
-#define fiv_io_model_entry_ref(e)    g_rc_box_acquire(e)
-#define fiv_io_model_entry_unref(e)  g_rc_box_release(e)
-
-FivIoModelEntry *const *fiv_io_model_get_files(FivIoModel *self, gsize *len);
-FivIoModelEntry *const *fiv_io_model_get_subdirs(FivIoModel *self, gsize *len);
-
 // --- Export ------------------------------------------------------------------
 
 /// Encodes a Cairo surface as a WebP bitstream, following the configuration.
diff --git a/fiv-sidebar.h b/fiv-sidebar.h
index 125119f..0cea059 100644
--- a/fiv-sidebar.h
+++ b/fiv-sidebar.h
@@ -17,7 +17,7 @@
 
 #pragma once
 
-#include "fiv-io.h"
+#include "fiv-io-model.h"
 
 #include <gtk/gtk.h>
 
diff --git a/fiv.c b/fiv.c
index d74bce3..dad88e2 100644
--- a/fiv.c
+++ b/fiv.c
@@ -38,6 +38,7 @@
 #include "fiv-browser.h"
 #include "fiv-collection.h"
 #include "fiv-io.h"
+#include "fiv-io-model.h"
 #include "fiv-sidebar.h"
 #include "fiv-thumbnail.h"
 #include "fiv-view.h"
diff --git a/meson.build b/meson.build
index 9d1ceca..f196d29 100644
--- a/meson.build
+++ b/meson.build
@@ -140,7 +140,7 @@ tiff_tables = custom_target('tiff-tables.h',
 desktops = ['fiv.desktop', 'fiv-browse.desktop']
 exe = executable('fiv', 'fiv.c', 'fiv-view.c', 'fiv-io.c', 'fiv-context-menu.c',
 	'fiv-browser.c', 'fiv-sidebar.c', 'fiv-thumbnail.c', 'fiv-collection.c',
-	'xdg.c', tiff_tables, gresources, rc, config,
+	'fiv-io-model.c', 'xdg.c', tiff_tables, gresources, rc, config,
 	install : true,
 	dependencies : dependencies,
 	win_subsystem : 'windows',