local longpress = require "awesome-longpress"
local beautiful = require "beautiful"
local posix = require "posix"
local wibox = require "wibox"
local gears = require "gears"
local fswidget = {
 mounts = {},
 ignoreMounts = {["/boot"]=true},
 ignoreDevs = {},
 iconSize = 96,
 iconPath = gears.filesystem.get_configuration_dir() .. "/awesome-fswidget/"
}
local fstypes = {}
local f = io.open("/proc/filesystems")
for line in f:lines() do
 if not line:match("nodev") then
  fstypes[line:match("%S+")] = true
 end
end

local function getMountedFilesystems()
 local f = io.open("/proc/mounts")
 for line in f:lines() do
  local dev,mp,fst,opt = line:match("(%S+)%s+(%S+)%s+(%S+)%s+(.+)")
  if fstypes[fst] and not fswidget.ignoreMounts[mp] and not fswidget.ignoreDevs[dev] then
   fswidget.mounts[dev] = fswidget.mounts[dev] or {}
   fswidget.mounts[dev][#fswidget.mounts[dev]+1] = mp
   fswidget.mounts[dev].device = dev
   if opt:match("ssd") then
    fswidget.mounts[dev].ssd = true
   end
  end
 end
end

local function chooseIcon(mount)
 local icon = "drive-harddisk"
 if mount.ssd then
  icon = "drive-harddisk-solidstate"
 end
 if mount.device:match("mmcblk") then
  icon = "media-memory-mmc"
 end
 return icon
end

local sizeTable = {[0] = "B", "K","M","G","T","P"}
local function formatSize(n)
 local i = 0
 while n > 1024 do
  n = n / 1024
  i = i + 1
 end
 return string.format("%0.1f%s",n,sizeTable[i])
end

local function updateWidget(self)
 local stat = posix.statvfs(self.mountpoint)
 if stat then
  local free, used, fraction = stat.bfree * stat.bsize, (stat.blocks - stat.bfree) * stat.bsize, (stat.blocks - stat.bfree) / stat.blocks
  self.fsbar.value = fraction
  self.fspercent.text = string.format("%.1f%%",fraction*100)
  self.fsused.text = formatSize(used)
  self.fsfree.text = formatSize(free)
 end
end

function fswidget.new(mount)
 local fs = mount[1]
 local fsbar = wibox.widget{
  widget = wibox.widget.progressbar,
  max_value = 1,
  forced_height = fswidget.iconSize / 6,
  border_color = beautiful.fg_focus,
  color = beautiful.bg_focus,
  background_color = beautiful.bg_normal,
 }
 local fspercent = wibox.widget{
  widget = wibox.widget.textbox,
 }
 local fsused = wibox.widget{
  widget = wibox.widget.textbox,
  visible = false
 }
 local fsfree = wibox.widget{
  widget = wibox.widget.textbox,
  visible = false
 }
 local w = wibox.widget{
  layout = wibox.layout.stack,
  wibox.widget{
   widget = wibox.widget.imagebox,
   forced_width = fswidget.iconSize,
   forced_height = fswidget.iconSize,
   image = string.format("%s/%s.svg", fswidget.iconPath, chooseIcon(mount))
  },
  wibox.container.place(wibox.widget{
    widget = wibox.widget.textbox,
    text = fs
   },"center","top"),
  wibox.container.place(fsbar,"center","bottom"),
  wibox.container.place(fspercent,"center","bottom"),
  wibox.container.place(fsused,"left","bottom"),
  wibox.container.place(fsfree,"right","bottom")
 }
 local c = wibox.container.constraint(w,nil,fswidget.iconSize,fswidget.iconSize)
 c.update, c.mountpoint, c.fsbar, c.fspercent, c.fsused, c.fsfree = updateWidget, fs, fsbar, fspercent, fsused, fsfree
 longpress.add(c, function()
  fspercent.visible = not fspercent.visible
  fsused.visible = not fsused.visible
  fsfree.visible = not fsfree.visible
 end)
 c:update()
 return c
end

function fswidget.all()
 local r = {}
 getMountedFilesystems()
 for k,v in pairs(fswidget.mounts) do
  r[#r+1] = fswidget.new(v)
 end
 return r
end

return fswidget