Useful lil' script to page through i3wm workspaces.

change_workspace.py

from collections import defaultdict
from sys import argv
from typing import Dict

from i3ipc import Connection


'''
Pages left or right through workspaces in i3wm, and also moves windows to left or right workspaces.

Add the following lines to ~/.config/i3/config to use with Page Up and Page Down:

bindsym $mod+Next exec python /path/to/script/change_workspace.py next
bindsym $mod+Prior exec python /path/to/script/change_workspace.py previous
bindsym $mod+Shift+Next exec python /path/to/script/change_workspace.py move_next
bindsym $mod+Shift+Prior exec python /path/to/script/change_workspace.py move_previous

'''


def get_args(command: str):
    return {
        'next': ('workspace {workspace}', 1),
        'previous': ('workspace {workspace}', -1),
        'move_next': ('move container to workspace {workspace}; workspace {workspace}', 1),
        'move_previous': ('move container to workspace {workspace}; workspace {workspace}', -1)
    }.get(command)


def parse_workspaces(workspaces: Dict):
    focused_output = None
    focused_workspace = None
    outputs = defaultdict(list)

    for workspace in workspaces:
        if workspace.get('focused') is True:
            focused_output = workspace.get('output')
            focused_workspace = workspace.get('num')
        outputs[workspace['output']].append(workspace.get('num'))
    return {
        'outputs': outputs,
        'focused_output': focused_output,
        'focused_workspace': focused_workspace
    }


def change_workspace(i3: Connection, command: str, modifier: int):
    parsed_workspaces = parse_workspaces(i3.get_workspaces())

    focused_workspace = parsed_workspaces.get('focused_workspace')
    focused_output = parsed_workspaces.get('focused_output')
    outputs = parsed_workspaces.get('outputs')

    workspaces_for_focused_output = outputs.get(focused_output)
    non_focused_outputs = {o: w for o, w in outputs.items() if o != focused_output}
    occupied_workspaces = [w for o, ws in non_focused_outputs.items() for w in ws]
    max_workspace_for_focused_output = max(workspaces_for_focused_output)
    max_workspace = max(occupied_workspaces + workspaces_for_focused_output)
    default = max_workspace_for_focused_output if modifier < 0 else max_workspace + 1
    if modifier > 0:
        max_workspace_for_focused_output += modifier
    end_of_range = 0 if modifier < 0 else max_workspace + 1
    success = False

    for x in range(focused_workspace + modifier, end_of_range, modifier):
        if success is False and (x in workspaces_for_focused_output or x not in occupied_workspaces):
            success = i3.command(command.format(workspace=x))
    success or i3.command(command.format(workspace=default))


if __name__ == '__main__':
    change_workspace(Connection(), *get_args(argv[1]))