swayipc/node.go

package swayipc

import (
	"encoding/json"
	"fmt"
)

const (
	NodeTypeRoot      = iota + 1 // A root node
	NodeTypeOutput               // An output node
	NodeTypeWorkspace            // A workspace
	NodeTypeCon                  // A container node (containing more nodes)
	NodeTypeFloating             // A floating node
)

// Node  can be an output,  a workspace, a container  or a container
// containing other containers.
type Node struct {
	ID                 int     `json:"id"`
	Type               string  `json:"type"` // output, workspace or container
	Name               string  `json:"name"` // workspace number or app name
	Output             string  `json:"output"`
	Nodes              []*Node `json:"nodes"`
	FloatingNodes      []*Node `json:"floating_nodes"`
	Focused            bool    `json:"focused"`
	Visible            bool    `json:"visible"`
	Urgent             bool    `json:"urgent"`
	Sticky             bool    `json:"sticky"`
	Border             string  `json:"border"`
	Layout             string  `json:"layout"`
	Orientation        string  `json:"orientation"`
	CurrentBorderWidth int     `json:"current_border_width"`
	Percent            float32 `json:"percent"`
	Focus              []int   `json:"focus"`
	Window             int     `json:"window"` // wayland native
	X11Window          string  `json:"app_id"` // x11 compat
	CurrentWorkspace   string  `json:"current_workspace"`
	Rect               Rect    `json:"rect"`
	WindowRect         Rect    `json:"window_rect"`
	DecoRect           Rect    `json:"deco_rect"`
	Geometry           Rect    `json:"geometry"`
}

// GetTree  returns   the  whole  information  tree,   which  contains
// everything from output to containers as a tree of nodes.  Each node
// has a  field 'Nodes' which points  to a list subnodes.   Some nodes
// also  have  a field  'FloatingNodes'  which  points  to a  list  of
// floating containers.
//
// The top level node is the "root" node.
//
// Use the returned node oject to further investigate the wm setup.
func (ipc *SwayIPC) GetTree() (*Node, error) {
	err := ipc.sendHeader(MsgGettTree, 0)
	if err != nil {
		return nil, err
	}

	payload, err := ipc.readResponse()
	if err != nil {
		return nil, err
	}

	node := &Node{}
	if err := json.Unmarshal(payload.Payload, &node); err != nil {
		return nil, fmt.Errorf("failed to unmarshal json: %w", err)
	}

	return node, nil
}

// FindFocused  returns   the  container   which  has   currently  the
// focus. Usually called on the root node.
func (node *Node) FindFocused() *Node {
	focused := searchFocused(node.Nodes)
	if focused == nil {
		return searchFocused(node.FloatingNodes)
	}

	return nil
}

// FindCurrentWorkspace returns  the  current  active
// workspace name. Usually  called  on  the  root node.
func (node *Node) FindCurrentWorkspace() string {
	return searchCurrentWorkspace(node.Nodes)
}

// searchCurrentWorkspace search for current workspace
func searchCurrentWorkspace(nodes []*Node) string {
	for _, node := range nodes {
		if node.CurrentWorkspace != "" {
			return node.CurrentWorkspace
		} else {
			return searchCurrentWorkspace(node.Nodes)
		}
	}

	return ""
}

// searchFocused recursively search focused node
func searchFocused(nodes []*Node) *Node {
	for _, node := range nodes {
		if node.Focused {
			return node
		} else {
			focused := searchFocused(node.Nodes)
			if focused == nil {
				return searchFocused(node.FloatingNodes)
			}
		}
	}

	return nil
}