status.lua

--- @alias battery_state 'Charging' | 'Discharging' | 'Empty' | 'Full' | 'Unknown'
--- @alias battery { state: battery_state, state_of_charge: number }

local M = {}

local wezterm = require 'wezterm'

--- @param battery battery state of charge, from 0.00 to 1.00
--- @return string
local function render_battery(battery)
   --- @type table<string, string>
   local icons = wezterm.nerdfonts
   local percent = battery.state_of_charge
   local formatted_percent = string.format('%.0f%%', percent * 100)

   local get_icon = function()
      local prefix = 'mdi_battery'
      if battery.state == 'Charging' then
         return icons[prefix .. '_charging']
      end

      --- @type string
      local icon_name

      if percent == 1 then
         icon_name = prefix
      else
         local suffix = math.max(1, math.ceil(percent * 10)) .. '0'
         icon_name = prefix .. '_' .. suffix
      end

      local color = percent <= 0.1 and 'Red' or 'Green'
      return wezterm.format {
         { Foreground = { AnsiColor = color } },
         { Text = icons[icon_name] }
      }
   end

   return string.format('%s %s', get_icon(), formatted_percent)
end

local function update_right_status(window)
   -- "Wed Mar 3 08:14"
   --- @type string
   local date = wezterm.strftime '%a %b %-d %H:%M'

   --- @type string
   local tilde = wezterm.format {
      { Foreground = { AnsiColor = 'Fuchsia' } },
      { Text = '~' }
   }

   --- @type string
   local battery

   for _, b in ipairs(wezterm.battery_info()) do
      battery = render_battery(b)
   end

   local status = string.format('%s %s %s ', battery, tilde, date)
   window:set_right_status(wezterm.format {
      { Text = status }
   })
end

function M.enable()
   wezterm.on('update-right-status', update_right_status)
end

return M