-- Events library
-- (c) Er2 2022 <er2@dismail.de>
-- Zlib License

require 'class'

class 'Events' {
  function(this)
    this._ev_ = {}
  end,

  _add = function(this, type, name, func)
    table.insert(this._ev_, {
      type = tostring(type),
      name = tostring(name),
      func = func,
    })
  end,

  on = function(this, name, func)
    this:_add('on', name, func)
  end,

  once = function(this, name, func)
    this:_add('once', name, func)
  end,

  off = function(this, func)
    for k, v in pairs(this._ev_) do
      if v.func == func
      then table.remove(this._ev_, k)
      end
    end
  end,

  _ev = function(this, t, i, name, ...)
    local v = t[i]
    if v.name == name then
      v.func(...)
      if v.type == 'once'
      then table.remove(t, i)
      end
    end
  end,

  emit = function(this, name, ...)
    local t = this._ev_
    for i = 1, #t do
      local v = t[i]
      if  type(v)      == 'table'
      and type(v.name) == 'string'
      and type(v.type) == 'string'
      and type(v.func) == 'function'
      then this:_ev(t, i, name, ...)
      else print 'Invalid event'
        if v then print(v, v.name, v.type, v.func)
        else print 'nil' end
      end
    end
  end,
}

class 'EventsThis' : inherits 'Events' {
  _ev = function(this, t, i, name, ...)
    local v = t[i]
    if v.name == name then
      v.func(this, ...)
      if v.type == 'once'
      then table.remove(t, i)
      end
    end
  end,
}