-- This project is licensed under the MIT License (see LICENSE).

--- Launch clients as panels.
--
-- @author James Reed <jcrd@tuta.io>
-- @copyright 2019-2020 James Reed
-- @module awesome-launch.panel

local awful = require("awful")
local gtable = require("gears.table")
local gtimer = require("gears.timer")
local launch = require("awesome-launch")

local panel = {}

--- Function to handle toggling of a panel client.
--
-- By default, the client's hidden state is toggled.
--
-- @param c The client being toggled.
-- @param state The toggle state: `true` if being toggled into view, `false`
-- otherwise.
-- @function panel.toggle_func
function panel.toggle_func(c, state)
    c.hidden = not state
end

--- Function to handle setup of a panel client.
--
-- By default, the client is hidden and made sticky.
--
-- @param c The client being setup.
-- @function panel.setup_func
function panel.setup_func(c)
    c.hidden = true
    c.sticky = true
end

-- TODO: Reapply args on restart with rule source.
-- See: https://github.com/awesomeWM/awesome/issues/2725
local function spawn(cmd, args)
    local cb = args.callback
    args.callback = function (c)
        c.floating = true
        c.skip_taskbar = true
        c.launch_panel = true
        awful.placement.scale(c, {to_percent=args.scale or 0.5})
        awful.placement.centered(c)
        if panel.setup_func then
            panel.setup_func(c)
        end
        c:connect_signal("unfocus", function ()
            gtimer.delayed_call(function ()
                local valid = pcall(function () return c.valid end) and c.valid
                if valid and not (client.focus and client.focus.floating) then
                    panel.toggle_func(c, false)
                end
            end)
        end)
        if cb then
            cb(c)
        end
        panel.toggle_func(c, true)
    end
    launch.spawn.single_instance(cmd, args)
end

local function toggle(c)
    if c == client.focus then
        panel.toggle_func(c, false)
    else
        panel.toggle_func(c, true)
        c:emit_signal("request::activate", "panel.toggle", {raise=true})
    end
end

--- Toggle the visibility of a panel, spawning the command if necessary.
--
-- A panel is a floating, centered client that can be scaled to a percentage of
-- its size.
--
-- @param cmd The command.
-- @param args Table containing the single instance ID and additional arguments for spawn
-- @param args.id Single instance ID.
-- @param args.props Properties to apply to the client.
-- @param args.pwd Pathname to the working directory for new clients.
-- @param args.timeout Seconds after which to stop waiting for a client to spawn.
-- @param args.callback Function to call with client when it spawns.
-- @param args.factory The factory to use (see wm-launch's -f flag).
-- @param args.systemd If true, run cmd with systemd-run.
-- @param args.firejail If true, run cmd with firejail.
-- @param args.filter Function to filter clients that are considered.
-- @param args.scale Percent to scale client (see awful.placement.scale).
-- @function panel.toggle
function panel.toggle(cmd, args)
    local c = launch.client.by_id(args.id)
    if c then
        toggle(c)
    else
        spawn(cmd, args)
    end
end

return panel