--[[
--   handle key- and mousebindings in a sane and readable way
--]]

-- needs
local awful         = require("awful")
local gears         = require("gears")
local notifications = require("strangesome.notifications")
local debug         = notifications.debug_enabled
local debug_msg     = notifications.debug_msg
local wrequire      = require("strangesome.loader").wrequire

-- define standard commands local to speed up things a little bit
local next          = next
local setmetatable  = setmetatable
local tonumber      = tonumber

-- strangesome.bindings
local bindings = { _NAME = "strangesome.bindings" }

local gearstable = awful.util.table or gears.table
local internalbindings = {}
local separator = "+"
local keyregex = "([^"..separator.."]+)"

-- define named keys with usable aliases
local named_keys = {
  { "Escape",               { "esc", "escape" } },
  { "Left",                 {} },
  { "Right",                {} },
  { "Up",                   {} },
  { "Down",                 {} },
  { "Enter",                {} },
  { "Return",               {} },
  { "Print",                {} },
  { "Space",                {} },
  { "Backspace",            {} },
  { "Tab",                  {} },
  { "XF86AudioMute",        {} },
  { "XF86HomePage",         {} },
  { "XF86Calculator",       {} },
  { "XF86AudioMedia",       {} },
  { "XF86AudioPrev",        {} },
  { "XF86AudioNext",        {} },
  { "XF86AudioPlay",        {} },
  { "XF86AudioStop",        {} },
  { "XF86MyComputer",       {} },
  { "XF86AudioRaiseVolume", {} },
  { "XF86AudioLowerVolume", {} },
  -- more to come...
}

local mod_keys = {
  { "Control", { "control", "ctrl" } },
  { "Shift",   {} },
  { "Mod1",    { "alt", "mod1" } },
  { "Mod4",    { "super", "meta", "mod4" } },
}

local mouse_keys = {
  { 1, { "left", "mouseleft", "leftkey", "leftclick" } },
  { 2, { "middle", "mousemiddle", "middlekey", "middleclick" } },
  { 3, { "right", "mouseright", "rightkey", "rightclick" } },
  { 4, { "up", "mouseup", "scrollup" } },
  { 5, { "down", "mousedown", "scrolldown" } },
  -- more to come...
}

--[[
--  targetmap may be a string or a table with one or two entries
--
--  map = {
--    { "Ctrl+Alt+Super+L", "Super+LeftClick", description, function() }
--  }
--]]
function bindings.addkeyandmousemap(targetmap, category, map)
  if type(targetmap) == "string" then
    targetkey   = targetmap.."_key"
    targetmouse = targetmap.."_mouse"
  elseif type(targetmap) == "table" then
    if #targetmap == 1 then
      targetkey   = targetmap[1].."_key"
      targetmouse = targetmap[1].."_mouse"
    elseif #targetmap == 2 then
      targetkey   = targetmap[1]
      targetmouse = targetmap[2]
    end
  else
    return nil
  end

  if type(internalbindings[targetkey]) == "nil" then internalbindings[targetkey] = {} end
  if type(internalbindings[targetmouse]) == "nil" then internalbindings[targetmouse] = {} end
  for _, mapentry in ipairs(map) do
    local keys     = mapentry[1]
    local mkeys    = mapentry[2]
    local desc     = mapentry[3]
    local bindfunc = mapentry[4]
    if keys then
      internalbindings[targetkey] = gearstable.join(internalbindings[targetkey],
        awful.key(getmodkeys(keys), getkey(keys), bindfunc, {description = desc, group = category})
      )
    end
    if mkeys then
      internalbindings[targetmouse] = gearstable.join(internalbindings[targetmouse],
        awful.button(getmodkeys(mkeys), getmousekey(mkeys), bindfunc)
      )
    end
  end
  return { keys = internalbindings[targetkey], mouse = internalbindings[targetmouse] }
end

--[[
--  map = {
--    { "Ctrl+Alt+Super+L", description, function() }
--  }
--]]
function bindings.addkeymap(target, category, map)
  if debug then debug_msg("Type of internalbindings["..target.."]: "..type(internalbindings[target])) end
  if type(internalbindings[target]) == "nil" then internalbindings[target] = {} end
  for _, mapentry in ipairs(map) do
    local keys     = mapentry[1]
    local desc     = mapentry[2]
    local bindfunc = mapentry[3]
    internalbindings[target] = gearstable.join(internalbindings[target],
      awful.key(getmodkeys(keys), getkey(keys), bindfunc, {description = desc, group = category})
    )
  end

  if debug then debug_msg("Type of internalbindings["..target.."]: "..type(internalbindings[target])) end
  return internalbindings[target]
end

function bindings.addmousemap(target, map)
  if debug then debug_msg("Type of internalbindings["..target.."]: "..type(internalbindings[target])) end
  if type(internalbindings[target]) == "nil" then internalbindings[target] = {} end
  for _, mapentry in ipairs(map) do
    local keys     = mapentry[1]
    local bindfunc = mapentry[2]
    internalbindings[target] = gearstable.join(internalbindings[target],
      awful.button(getmodkeys(keys), getmousekey(keys), bindfunc)
    )
  end

  if debug then debug_msg("Type of internalbindings["..target.."]: "..type(internalbindings[target])) end
  return internalbindings[target]
end

function bindings.export(target)
  if type(internalbindings[target]) == "nil" then return {} end
  return internalbindings[target]
end

function getmodkeys(keys)
  local modkeys = {}
  local mkey

  for key in string.gmatch(keys, keyregex) do
    mkey = ismodkey(key)
    if mkey then
      modkeys[#modkeys+1] = mkey
    end
  end

  return modkeys
end

function getkey(keys)
  local sepregex = "["..separator.."]["..separator.."]"
  local key = ""
  for str in string.gmatch(keys, keyregex) do
    -- single char, always lower case
    if string.len(str) == 1 then
      key = string.lower(str) 
    -- named key, see table named_keys above
    elseif isnamedkey(str) then
      key = isnamedkey(str)
    -- match separator key, e.g in "Alt+Super++" for Alt, Super and "+"
    elseif string.match(keys, sepregex) then
      key = string.lower(separator)
    end
  end

  return key
end

function getmousekey(keys)
  local keyregex = "([^"..separator.."]+)"
  local key = 0
  local mkey
  for str in string.gmatch(keys, keyregex) do
    -- is number and between 1 and 5
    if type(str.tonumber) == "number" then
      local num = str.tonumber
      if num > 0 and num < 6  then key = num end
    -- mousekey, see table mouse_keys above (integers 1 to 5)
    elseif ismousekey(str) then
      key = ismousekey(str)
    end
  end

  return key
end

function isnamedkey(key)
  -- there are no named keys with length 1
  if string.len(key) == 1 then return false end
  return check_keys_table(key, named_keys)
end

function ismodkey(key)
  return check_keys_table(key, mod_keys)
end

function ismousekey(key)
  return check_keys_table(key, mouse_keys)
end

function check_keys_table(key, table)
  for _, entry in ipairs(table) do
    local tkey    = entry[1]
    local aliases = entry[2]
    if next(aliases) == nil then
      --no aliases given, check against tkey
      if string.lower(key) == string.lower(tkey) then return tkey end
    else
      for _, alias in ipairs(aliases) do
        if string.lower(key) == string.lower(alias) then return tkey end
      end
    end
  end
  return false
end


return setmetatable(bindings, { __index = wrequire })