hammerspoon config

init.lua

-- hs.hotkey.bind({'cmd', 'shift'}, 'q', function()
--   hs.eventtap.keyStroke({}, "`", 0)
--   -- hs.alert.show('hi')
-- end)

-- four item tuples:
--   fromMod, fromKey, toMod, toKey
KEYMAP = {
  {{'cmd', 'shift'}, 'q', {}, '`'}, -- backtick shortcut
  {{'cmd'}, 'escape', {'cmd'}, '`'}, -- cycle windows via cmd+esc
  {{'alt'}, 'v', {'cmd'}, 'v'}, -- remap pasting until karabiner is fixed
  {{"ctrl", "shift"}, "j", {'alt'}, 'left'}, -- jump left
  {{"ctrl", "shift"}, "k", {'alt'}, 'right'}, -- jump right
  {{'ctrl', 'shift'}, 'i', {'cmd'}, 'up'},  -- jump to beginning of file
  {{'ctrl', 'shift'}, 'n', {'cmd'}, 'down'},  -- jump to end of file
  {{'ctrl', 'cmd'}, 'j', {'cmd'}, 'left'}, -- jump beginning of line
  {{'ctrl', 'cmd'}, 'k', {'cmd'}, 'right'}, -- end of line
  {{'ctrl', 'shift'}, 'p', {}, 'delete'},
  {{'cmd', 'shift'}, 'l', {'cmd', 'shift'}, 'right'}, -- select to the end of the line
  {{'cmd', 'shift'}, 'j', {'cmd', 'shift'}, 'left'}
}

for _, hotkeyVals in ipairs(KEYMAP) do
  local fromMods, fromKey, toMods, toKey = table.unpack(hotkeyVals)
  local toKeyStroke = function()
    hs.eventtap.keyStroke(toMods, toKey, 0)
  end
  hs.hotkey.bind(fromMods, fromKey, toKeyStroke, nil, toKeyStroke)
end

-- make double-tap control be esc
local timer    = require("hs.timer")
local eventtap = require("hs.eventtap")

local events   = eventtap.event.types
local module   = {}

-- ho quickly must the two single ctrl taps occur?
module.timeFrame = 0.2

-- wht to do when the double tap of ctrl occurs
module.action = function()
  hs.eventtap.keyStroke({}, 'escape', 0)
end

local timeFirstControl, firstDown, secondDown = 0, false, false

-- verify that no keyboard flags are being pressed
local noFlags = function(ev)
    local result = true
    for k,v in pairs(ev:getFlags()) do
        if v then
            result = false
            break
        end
    end
    return result
end

-- verify that *only* the ctrl key flag is being pressed
local onlyCtrl = function(ev)
    local result = ev:getFlags().ctrl
    for k,v in pairs(ev:getFlags()) do
        if k ~= "ctrl" and v then
            result = false
            break
        end
    end
    return result
end

-- the actual workhorse

module.eventWatcher = eventtap.new({events.flagsChanged, events.keyDown}, function(ev)
    -- if it's been too long; previous state doesn't matter
    if (timer.secondsSinceEpoch() - timeFirstControl) > module.timeFrame then
        timeFirstControl, firstDown, secondDown = 0, false, false
    end

    if ev:getType() == events.flagsChanged then
        if noFlags(ev) and firstDown and secondDown then -- ctrl up and we've seen two, so do action
            if module.action then module.action() end
            timeFirstControl, firstDown, secondDown = 0, false, false
        elseif onlyCtrl(ev) and not firstDown then         -- ctrl down and it's a first
            firstDown = true
            timeFirstControl = timer.secondsSinceEpoch()
        elseif onlyCtrl(ev) and firstDown then             -- ctrl down and it's the second
            secondDown = true
        elseif not noFlags(ev) then                        -- otherwise reset and start over
            timeFirstControl, firstDown, secondDown = 0, false, false
        end
    else -- it was a key press, so not a lone ctrl char -- we don't care about it
        timeFirstControl, firstDown, secondDown = 0, false, false
    end
    return false
end):start()