--- Module for describing an action in a 'declarative' way
-- @classmod lqc.fsm.action
-- @alias Action
local Action = {}
local Action_mt = {
    __index = Action,
}

--- Creates a new action.
-- @param var (Symbolic) variable to store the result of the action in
-- @param cmd Command that was called during this action
-- @param command_generator Generator that generated the command, used for shrinking the command
-- @return new action object
function Action.new(var, cmd, command_generator) -- TODO rename to args_generators
    if var == nil then
        error 'Need to provide variable to action object!'
    end
    if cmd == nil then
        error 'Need to provide command to action object!'
    end

    local action = {
        variable = var,
        command = cmd,
        cmd_gen = command_generator,
    }
    return setmetatable(action, Action_mt)
end

--- Returns a string representation of the action
-- @return string representation of the action
function Action:to_string()
    return '{ set, ' .. self.variable:to_string() .. ', ' .. self.command:to_string() .. ' }'
end

return Action