Implement type safe arguments and demote sway_container

This commit changes the meaning of sway_container so that it only refers
to layout containers and view containers. Workspaces, outputs and the
root are no longer known as containers. Instead, root, outputs,
workspaces and containers are all a type of node, and containers come in
two types: layout containers and view containers.

In addition to the above, this implements type safe variables. This
means we use specific types such as sway_output and sway_workspace
instead of generic containers or nodes. However, it's worth noting that
in a few places places (eg. seat focus and transactions) referring to
them in a generic way is unavoidable which is why we still use nodes in
some places.

If you want a TL;DR, look at node.h, as well as the struct definitions
for root, output, workspace and container. Note that sway_output now
contains a workspaces list, and workspaces now contain a tiling and
floating list, and containers now contain a pointer back to the
workspace.

There are now functions for seat_get_focused_workspace and
seat_get_focused_container. The latter will return NULL if a workspace
itself is focused. Most other seat functions like seat_get_focus and
seat_set_focus now accept and return nodes.

In the config->handler_context struct, current_container has been
replaced with three pointers: node, container and workspace. node is the
same as what current_container was, while workspace is the workspace
that the node resides on and container is the actual container, which
may be NULL if a workspace itself is focused.

The global root_container variable has been replaced with one simply
called root, which is a pointer to the sway_root instance.

The way outputs are created, enabled, disabled and destroyed has
changed. Previously we'd wrap the sway_output in a container when it is
enabled, but as we don't have containers any more it needs a different
approach. The output_create and output_destroy functions previously
created/destroyed the container, but now they create/destroy the
sway_output. There is a new function output_disable to disable an output
without destroying it.

Containers have a new view property. If this is populated then the
container is a view container, otherwise it's a layout container. Like
before, this property is immutable for the life of the container.

Containers have both a `sway_container *parent` and
`sway_workspace *workspace`. As we use specific types now, parent cannot
point to a workspace so it'll be NULL for containers which are direct
children of the workspace. The workspace property is set for all
containers, except those which are hidden in the scratchpad as they have
no workspace.

In some cases we need to refer to workspaces in a container-like way.
For example, workspaces have layout and children, but when using
specific types this makes it difficult. Likewise, it's difficult for a
container to get its parent's layout when the parent could be another
container or a workspace. To make it easier, some helper functions have
been created: container_parent_layout and container_get_siblings.

container_remove_child has been renamed to container_detach and
container_replace_child has been renamed to container_replace.

`container_handle_fullscreen_reparent(con, old_parent)` has had the
old_parent removed. We now unfullscreen the workspace when detaching the
container, so this function is simplified and only needs one argument
now.

container_notify_subtree_changed has been renamed to
container_update_representation. This is more descriptive of its
purpose. I also wanted to be able to call it with whatever container was
changed rather than the container's parent, which makes bubbling up to
the workspace easier.

There are now state structs per node thing. ie. sway_output_state,
sway_workspace_state and sway_container_state.

The focus, move and layout commands have been completely refactored to
work with the specific types. I considered making these a separate PR,
but I'd be backporting my changes only to replace them again, and it's
easier just to test everything at once.

1 files changed, 208 insertions, 140 deletions

diff --git a/sway/tree/output.c b/sway/tree/output.c
index 6601220b..d72eb1a1 100644
--- a/sway/tree/output.c
+++ b/sway/tree/output.c
@@ -2,28 +2,31 @@
 #include <ctype.h>
 #include <string.h>
 #include <strings.h>
+#include <wlr/types/wlr_output_damage.h>
 #include "sway/ipc-server.h"
+#include "sway/layers.h"
 #include "sway/output.h"
 #include "sway/tree/arrange.h"
 #include "sway/tree/output.h"
 #include "sway/tree/workspace.h"
 #include "log.h"
+#include "util.h"
 
-static void restore_workspaces(struct sway_container *output) {
+static void restore_workspaces(struct sway_output *output) {
         // Workspace output priority
-        for (int i = 0; i < root_container.children->length; i++) {
-                struct sway_container *other = root_container.children->items[i];
+        for (int i = 0; i < root->outputs->length; i++) {
+                struct sway_output *other = root->outputs->items[i];
                 if (other == output) {
                         continue;
                 }
 
-                for (int j = 0; j < other->children->length; j++) {
-                        struct sway_container *ws = other->children->items[j];
-                        struct sway_container *highest =
+                for (int j = 0; j < other->workspaces->length; j++) {
+                        struct sway_workspace *ws = other->workspaces->items[j];
+                        struct sway_output *highest =
                                 workspace_output_get_highest_available(ws, NULL);
                         if (highest == output) {
-                                container_remove_child(ws);
-                                container_add_child(output, ws);
+                                workspace_detach(ws);
+                                output_add_workspace(output, ws);
                                 ipc_event_workspace(NULL, ws, "move");
                                 j--;
                         }
@@ -31,111 +34,111 @@ static void restore_workspaces(struct sway_container *output) {
         }
 
         // Saved workspaces
-        list_t *saved = root_container.sway_root->saved_workspaces;
-        for (int i = 0; i < saved->length; ++i) {
-                struct sway_container *ws = saved->items[i];
-                container_add_child(output, ws);
+        for (int i = 0; i < root->saved_workspaces->length; ++i) {
+                struct sway_workspace *ws = root->saved_workspaces->items[i];
+                output_add_workspace(output, ws);
                 ipc_event_workspace(NULL, ws, "move");
         }
-        saved->length = 0;
+        root->saved_workspaces->length = 0;
 
         output_sort_workspaces(output);
 }
 
-struct sway_container *output_create(
-                struct sway_output *sway_output) {
-        const char *name = sway_output->wlr_output->name;
-        char identifier[128];
-        output_get_identifier(identifier, sizeof(identifier), sway_output);
+struct sway_output *output_create(struct wlr_output *wlr_output) {
+        struct sway_output *output = calloc(1, sizeof(struct sway_output));
+        node_init(&output->node, N_OUTPUT, output);
+        output->wlr_output = wlr_output;
+        wlr_output->data = output;
 
-        struct output_config *oc = NULL, *all = NULL;
-        for (int i = 0; i < config->output_configs->length; ++i) {
-                struct output_config *cur = config->output_configs->items[i];
+        wl_signal_add(&wlr_output->events.destroy, &output->destroy);
 
-                if (strcasecmp(name, cur->name) == 0 ||
-                                strcasecmp(identifier, cur->name) == 0) {
-                        wlr_log(WLR_DEBUG, "Matched output config for %s", name);
-                        oc = cur;
-                }
-                if (strcasecmp("*", cur->name) == 0) {
-                        wlr_log(WLR_DEBUG, "Matched wildcard output config for %s", name);
-                        all = cur;
-                }
+        wl_list_insert(&root->all_outputs, &output->link);
 
-                if (oc && all) {
-                        break;
-                }
-        }
-        if (!oc) {
-                oc = all;
+        if (!wl_list_empty(&wlr_output->modes)) {
+                struct wlr_output_mode *mode =
+                        wl_container_of(wlr_output->modes.prev, mode, link);
+                wlr_output_set_mode(wlr_output, mode);
         }
 
-        if (oc && !oc->enabled) {
-                return NULL;
-        }
+        output->workspaces = create_list();
+        output->current.workspaces = create_list();
 
-        struct sway_container *output = container_create(C_OUTPUT);
-        output->sway_output = sway_output;
-        output->name = strdup(name);
-        if (output->name == NULL) {
-                output_begin_destroy(output);
-                return NULL;
-        }
+        return output;
+}
 
+void output_enable(struct sway_output *output, struct output_config *oc) {
+        if (!sway_assert(!output->enabled, "output is already enabled")) {
+                return;
+        }
+        struct wlr_output *wlr_output = output->wlr_output;
+        output->enabled = true;
         apply_output_config(oc, output);
-        container_add_child(&root_container, output);
-        load_swaybars();
-
-        struct wlr_box size;
-        wlr_output_effective_resolution(sway_output->wlr_output, &size.width,
-                &size.height);
-        output->width = size.width;
-        output->height = size.height;
+        list_add(root->outputs, output);
 
         restore_workspaces(output);
 
-        if (!output->children->length) {
+        if (!output->workspaces->length) {
                 // Create workspace
-                char *ws_name = workspace_next_name(output->name);
+                char *ws_name = workspace_next_name(wlr_output->name);
                 wlr_log(WLR_DEBUG, "Creating default workspace %s", ws_name);
-                struct sway_container *ws = workspace_create(output, ws_name);
+                struct sway_workspace *ws = workspace_create(output, ws_name);
                 // Set each seat's focus if not already set
                 struct sway_seat *seat = NULL;
                 wl_list_for_each(seat, &input_manager->seats, link) {
                         if (!seat->has_focus) {
-                                seat_set_focus(seat, ws);
+                                seat_set_focus(seat, &ws->node);
                         }
                 }
                 free(ws_name);
         }
 
-        container_create_notify(output);
-        return output;
+        size_t len = sizeof(output->layers) / sizeof(output->layers[0]);
+        for (size_t i = 0; i < len; ++i) {
+                wl_list_init(&output->layers[i]);
+        }
+        wl_signal_init(&output->events.destroy);
+
+        input_manager_configure_xcursor(input_manager);
+
+        wl_signal_add(&wlr_output->events.mode, &output->mode);
+        wl_signal_add(&wlr_output->events.transform, &output->transform);
+        wl_signal_add(&wlr_output->events.scale, &output->scale);
+        wl_signal_add(&output->damage->events.frame, &output->damage_frame);
+        wl_signal_add(&output->damage->events.destroy, &output->damage_destroy);
+
+        output_add_listeners(output);
+
+        wl_signal_emit(&root->events.new_node, &output->node);
+
+        load_swaybars();
+
+        arrange_layers(output);
+        arrange_root();
 }
 
-static void output_evacuate(struct sway_container *output) {
-        if (!output->children->length) {
+static void output_evacuate(struct sway_output *output) {
+        if (!output->workspaces->length) {
                 return;
         }
-        struct sway_container *fallback_output = NULL;
-        if (root_container.children->length > 1) {
-                fallback_output = root_container.children->items[0];
+        struct sway_output *fallback_output = NULL;
+        if (root->outputs->length > 1) {
+                fallback_output = root->outputs->items[0];
                 if (fallback_output == output) {
-                        fallback_output = root_container.children->items[1];
+                        fallback_output = root->outputs->items[1];
                 }
         }
 
-        while (output->children->length) {
-                struct sway_container *workspace = output->children->items[0];
+        while (output->workspaces->length) {
+                struct sway_workspace *workspace = output->workspaces->items[0];
 
-                container_remove_child(workspace);
+                workspace_detach(workspace);
 
                 if (workspace_is_empty(workspace)) {
                         workspace_begin_destroy(workspace);
                         continue;
                 }
 
-                struct sway_container *new_output =
+                struct sway_output *new_output =
                         workspace_output_get_highest_available(workspace, output);
                 if (!new_output) {
                         new_output = fallback_output;
@@ -143,39 +146,31 @@ static void output_evacuate(struct sway_container *output) {
 
                 if (new_output) {
                         workspace_output_add_priority(workspace, new_output);
-                        container_add_child(new_output, workspace);
+                        output_add_workspace(new_output, workspace);
                         output_sort_workspaces(new_output);
                         ipc_event_workspace(NULL, workspace, "move");
                 } else {
-                        list_add(root_container.sway_root->saved_workspaces, workspace);
+                        list_add(root->saved_workspaces, workspace);
                 }
         }
 }
 
-void output_destroy(struct sway_container *output) {
-        if (!sway_assert(output->type == C_OUTPUT, "Expected an output")) {
+void output_destroy(struct sway_output *output) {
+        if (!sway_assert(output->node.destroying,
+                                "Tried to free output which wasn't marked as destroying")) {
                 return;
         }
-        if (!sway_assert(output->destroying,
-                                "Tried to free output which wasn't marked as destroying")) {
+        if (!sway_assert(output->wlr_output == NULL,
+                                "Tried to free output which still had a wlr_output")) {
                 return;
         }
-        if (!sway_assert(output->ntxnrefs == 0, "Tried to free output "
+        if (!sway_assert(output->node.ntxnrefs == 0, "Tried to free output "
                                 "which is still referenced by transactions")) {
                 return;
         }
-        free(output->name);
-        free(output->formatted_title);
-        wlr_texture_destroy(output->title_focused);
-        wlr_texture_destroy(output->title_focused_inactive);
-        wlr_texture_destroy(output->title_unfocused);
-        wlr_texture_destroy(output->title_urgent);
-        list_free(output->children);
-        list_free(output->current.children);
-        list_free(output->outputs);
+        list_free(output->workspaces);
+        list_free(output->current.workspaces);
         free(output);
-
-        // NOTE: We don't actually destroy the sway_output here
 }
 
 static void untrack_output(struct sway_container *con, void *data) {
@@ -186,76 +181,131 @@ static void untrack_output(struct sway_container *con, void *data) {
         }
 }
 
-void output_begin_destroy(struct sway_container *output) {
-        if (!sway_assert(output->type == C_OUTPUT, "Expected an output")) {
+void output_disable(struct sway_output *output) {
+        if (!sway_assert(output->enabled, "Expected an enabled output")) {
                 return;
         }
-        wlr_log(WLR_DEBUG, "OUTPUT: Destroying output '%s'", output->name);
+        wlr_log(WLR_DEBUG, "Disabling output '%s'", output->wlr_output->name);
         wl_signal_emit(&output->events.destroy, output);
 
         output_evacuate(output);
 
-        output->destroying = true;
-        container_set_dirty(output);
+        root_for_each_container(untrack_output, output);
+
+        int index = list_find(root->outputs, output);
+        list_del(root->outputs, index);
 
-        root_for_each_container(untrack_output, output->sway_output);
+        wl_list_remove(&output->mode.link);
+        wl_list_remove(&output->transform.link);
+        wl_list_remove(&output->scale.link);
+        wl_list_remove(&output->damage_destroy.link);
+        wl_list_remove(&output->damage_frame.link);
 
-        wl_list_remove(&output->sway_output->mode.link);
-        wl_list_remove(&output->sway_output->transform.link);
-        wl_list_remove(&output->sway_output->scale.link);
-        wl_list_remove(&output->sway_output->damage_destroy.link);
-        wl_list_remove(&output->sway_output->damage_frame.link);
+        output->enabled = false;
 
-        output->sway_output->swayc = NULL;
-        output->sway_output = NULL;
+        arrange_root();
+}
 
-        if (output->parent) {
-                container_remove_child(output);
+void output_begin_destroy(struct sway_output *output) {
+        if (!sway_assert(!output->enabled, "Expected a disabled output")) {
+                return;
         }
+        wlr_log(WLR_DEBUG, "Destroying output '%s'", output->wlr_output->name);
+
+        output->node.destroying = true;
+        node_set_dirty(&output->node);
+
+        wl_list_remove(&output->link);
+        wl_list_remove(&output->destroy.link);
+        output->wlr_output->data = NULL;
+        output->wlr_output = NULL;
 }
 
-struct sway_container *output_from_wlr_output(struct wlr_output *output) {
-        if (output == NULL) {
+struct output_config *output_find_config(struct sway_output *output) {
+        const char *name = output->wlr_output->name;
+        char identifier[128];
+        output_get_identifier(identifier, sizeof(identifier), output);
+
+        struct output_config *oc = NULL, *all = NULL;
+        for (int i = 0; i < config->output_configs->length; ++i) {
+                struct output_config *cur = config->output_configs->items[i];
+
+                if (strcasecmp(name, cur->name) == 0 ||
+                                strcasecmp(identifier, cur->name) == 0) {
+                        wlr_log(WLR_DEBUG, "Matched output config for %s", name);
+                        oc = cur;
+                }
+                if (strcasecmp("*", cur->name) == 0) {
+                        wlr_log(WLR_DEBUG, "Matched wildcard output config for %s", name);
+                        all = cur;
+                }
+
+                if (oc && all) {
+                        break;
+                }
+        }
+        if (!oc) {
+                oc = all;
+        }
+
+        if (oc && !oc->enabled) {
                 return NULL;
         }
-        for (int i = 0; i < root_container.children->length; ++i) {
-                struct sway_container *o = root_container.children->items[i];
-                if (o->type == C_OUTPUT && o->sway_output->wlr_output == output) {
-                        return o;
-                }
+        return oc;
+}
+
+struct sway_output *output_from_wlr_output(struct wlr_output *output) {
+        return output->data;
+}
+
+struct sway_output *output_get_in_direction(struct sway_output *reference,
+                enum movement_direction direction) {
+        enum wlr_direction wlr_dir = 0;
+        if (!sway_assert(sway_dir_to_wlr(direction, &wlr_dir),
+                                "got invalid direction: %d", direction)) {
+                return NULL;
         }
-        return NULL;
+        int lx = reference->wlr_output->lx + reference->wlr_output->width / 2;
+        int ly = reference->wlr_output->ly + reference->wlr_output->height / 2;
+        struct wlr_output *wlr_adjacent = wlr_output_layout_adjacent_output(
+                        root->output_layout, wlr_dir, reference->wlr_output, lx, ly);
+        if (!wlr_adjacent) {
+                return NULL;
+        }
+        return output_from_wlr_output(wlr_adjacent);
 }
 
-void output_for_each_workspace(struct sway_container *output,
-                void (*f)(struct sway_container *con, void *data), void *data) {
-        if (!sway_assert(output->type == C_OUTPUT, "Expected an output")) {
-                return;
+void output_add_workspace(struct sway_output *output,
+                struct sway_workspace *workspace) {
+        if (workspace->output) {
+                workspace_detach(workspace);
         }
-        for (int i = 0; i < output->children->length; ++i) {
-                struct sway_container *workspace = output->children->items[i];
+        list_add(output->workspaces, workspace);
+        workspace->output = output;
+        node_set_dirty(&output->node);
+        node_set_dirty(&workspace->node);
+}
+
+void output_for_each_workspace(struct sway_output *output,
+                void (*f)(struct sway_workspace *ws, void *data), void *data) {
+        for (int i = 0; i < output->workspaces->length; ++i) {
+                struct sway_workspace *workspace = output->workspaces->items[i];
                 f(workspace, data);
         }
 }
 
-void output_for_each_container(struct sway_container *output,
+void output_for_each_container(struct sway_output *output,
                 void (*f)(struct sway_container *con, void *data), void *data) {
-        if (!sway_assert(output->type == C_OUTPUT, "Expected an output")) {
-                return;
-        }
-        for (int i = 0; i < output->children->length; ++i) {
-                struct sway_container *workspace = output->children->items[i];
+        for (int i = 0; i < output->workspaces->length; ++i) {
+                struct sway_workspace *workspace = output->workspaces->items[i];
                 workspace_for_each_container(workspace, f, data);
         }
 }
 
-struct sway_container *output_find_workspace(struct sway_container *output,
-                bool (*test)(struct sway_container *con, void *data), void *data) {
-        if (!sway_assert(output->type == C_OUTPUT, "Expected an output")) {
-                return NULL;
-        }
-        for (int i = 0; i < output->children->length; ++i) {
-                struct sway_container *workspace = output->children->items[i];
+struct sway_workspace *output_find_workspace(struct sway_output *output,
+                bool (*test)(struct sway_workspace *ws, void *data), void *data) {
+        for (int i = 0; i < output->workspaces->length; ++i) {
+                struct sway_workspace *workspace = output->workspaces->items[i];
                 if (test(workspace, data)) {
                         return workspace;
                 }
@@ -263,14 +313,11 @@ struct sway_container *output_find_workspace(struct sway_container *output,
         return NULL;
 }
 
-struct sway_container *output_find_container(struct sway_container *output,
+struct sway_container *output_find_container(struct sway_output *output,
                 bool (*test)(struct sway_container *con, void *data), void *data) {
-        if (!sway_assert(output->type == C_OUTPUT, "Expected an output")) {
-                return NULL;
-        }
         struct sway_container *result = NULL;
-        for (int i = 0; i < output->children->length; ++i) {
-                struct sway_container *workspace = output->children->items[i];
+        for (int i = 0; i < output->workspaces->length; ++i) {
+                struct sway_workspace *workspace = output->workspaces->items[i];
                 if ((result = workspace_find_container(workspace, test, data))) {
                         return result;
                 }
@@ -279,8 +326,8 @@ struct sway_container *output_find_container(struct sway_container *output,
 }
 
 static int sort_workspace_cmp_qsort(const void *_a, const void *_b) {
-        struct sway_container *a = *(void **)_a;
-        struct sway_container *b = *(void **)_b;
+        struct sway_workspace *a = *(void **)_a;
+        struct sway_workspace *b = *(void **)_b;
 
         if (isdigit(a->name[0]) && isdigit(b->name[0])) {
                 int a_num = strtol(a->name, NULL, 10);
@@ -294,6 +341,27 @@ static int sort_workspace_cmp_qsort(const void *_a, const void *_b) {
         return 0;
 }
 
-void output_sort_workspaces(struct sway_container *output) {
-        list_stable_sort(output->children, sort_workspace_cmp_qsort);
+void output_sort_workspaces(struct sway_output *output) {
+        list_stable_sort(output->workspaces, sort_workspace_cmp_qsort);
+}
+
+void output_get_box(struct sway_output *output, struct wlr_box *box) {
+        box->x = output->wlr_output->lx;
+        box->y = output->wlr_output->ly;
+        box->width = output->wlr_output->width;
+        box->height = output->wlr_output->height;
+}
+
+enum sway_container_layout output_get_default_layout(
+                struct sway_output *output) {
+        if (config->default_layout != L_NONE) {
+                return config->default_layout;
+        }
+        if (config->default_orientation != L_NONE) {
+                return config->default_orientation;
+        }
+        if (output->wlr_output->height > output->wlr_output->width) {
+                return L_VERT;
+        }
+        return L_HORIZ;
 }