lua/clever_f/action_facade.lua


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local domain = require("clever_f.domain")
local sequence_coordinator = require("clever_f.sequence_coordinator")

local M = {}
local ActionFacade = {}
ActionFacade.__index = ActionFacade
M.ActionFacade = ActionFacade

local facade_records = setmetatable({}, { __mode = "k" })

local function fail(message, level)
  error(message, (level or 1) + 1)
end

function ActionFacade.new(options)
  if ActionFacade.is(options) then
    return options
  end
  local coordinator
  if sequence_coordinator.SequenceCoordinator.is(options) then
    coordinator = options
  elseif type(options) == "table" then
    coordinator = options.coordinator
      or options.sequence_coordinator
      or sequence_coordinator.new(options)
  else
    fail("ActionFacade options must be a table", 2)
  end
  if not sequence_coordinator.SequenceCoordinator.is(coordinator) then
    fail("ActionFacade requires a SequenceCoordinator", 2)
  end

  local facade = setmetatable({}, ActionFacade)
  facade_records[facade] = { coordinator = coordinator }
  return facade
end

function ActionFacade.is(value)
  return type(value) == "table" and facade_records[value] ~= nil
end

function ActionFacade:coordinator()
  return facade_records[self].coordinator
end

function ActionFacade:primary(descriptor)
  local outcome = self:coordinator():primary(descriptor)
  if not domain.ActionOutcome.is(outcome) then
    fail("SequenceCoordinator must return an ActionOutcome", 2)
  end
  return outcome
end

ActionFacade.invoke_primary = ActionFacade.primary
ActionFacade.start = ActionFacade.primary

function M.new(options)
  return ActionFacade.new(options)
end

setmetatable(M, {
  __call = function(_, options)
    return ActionFacade.new(options)
  end,
})

return M