# Tests for ModuleRegistry (R/module-registry.R): module registration, retrieval, aliasing, attachment

test_that("ModuleRegistry requires a Env", {
  expect_error(
    arl:::ModuleRegistry$new(NULL),
    "ModuleRegistry requires a Env"
  )
  expect_error(
    arl:::ModuleRegistry$new("not an env"),
    "ModuleRegistry requires a Env"
  )
})

test_that("ModuleRegistry initializes with Env", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)

  expect_true(inherits(registry, "ArlModuleRegistry"))
  expect_identical(registry$arl_env, arl_env)

  # Should create the registry environment
  reg_env <- arl_env$module_registry_env(create = FALSE)
  expect_true(!is.null(reg_env))
  expect_true(is.environment(reg_env))
})

# Module registration tests
test_that("register() requires valid name", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  expect_error(
    registry$register(123, mod_env, c("foo")),
    "module name must be a single string"
  )
  expect_error(
    registry$register(c("a", "b"), mod_env, c("foo")),
    "module name must be a single string"
  )
  expect_error(
    registry$register(character(0), mod_env, c("foo")),
    "module name must be a single string"
  )
})

test_that("register() creates module entry", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()
  mod_env$foo <- 42

  entry <- registry$register("test-mod", mod_env, c("foo"), path = "/path/to/test.arl")

  expect_true(is.environment(entry))
  expect_identical(entry$env, mod_env)
  expect_equal(entry$exports, c("foo"))
  expect_equal(entry$path, "/path/to/test.arl")
})

test_that("register() locks the entry environment", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  entry <- registry$register("test-mod", mod_env, c("foo"))

  # Entry should be locked
  expect_true(environmentIsLocked(entry))
  expect_true(bindingIsLocked("env", entry))
  expect_true(bindingIsLocked("exports", entry))
  expect_true(bindingIsLocked("path", entry))
})

test_that("register() prevents duplicate registration", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  registry$register("test-mod", mod_env, c("foo"))

  expect_error(
    registry$register("test-mod", new.env(), c("bar")),
    "module 'test-mod' is already defined"
  )
})

test_that("register() locks binding in registry", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  registry$register("test-mod", mod_env, c("foo"))

  reg_env <- arl_env$module_registry_env(create = FALSE)
  expect_true(bindingIsLocked("test-mod", reg_env))
})

test_that("register() handles empty exports", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  entry <- registry$register("test-mod", mod_env, character())

  expect_equal(entry$exports, character())
})

test_that("register() handles NULL path", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  entry <- registry$register("test-mod", mod_env, c("foo"))

  expect_null(entry$path)
})

# Module retrieval tests
test_that("exists() returns FALSE for missing modules", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)

  expect_false(registry$exists("nonexistent"))
})

test_that("exists() returns TRUE for registered modules", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  registry$register("test-mod", mod_env, c("foo"))

  expect_true(registry$exists("test-mod"))
})

test_that("exists() handles invalid input gracefully", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)

  expect_false(registry$exists(NULL))
  expect_false(registry$exists(123))
  expect_false(registry$exists(c("a", "b")))
})

test_that("get() returns NULL for missing modules", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)

  expect_null(registry$get("nonexistent"))
})

test_that("get() returns entry for registered modules", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()
  mod_env$foo <- 42

  registry$register("test-mod", mod_env, c("foo"), path = "/test.arl")
  entry <- registry$get("test-mod")

  expect_true(is.environment(entry))
  expect_identical(entry$env, mod_env)
  expect_equal(entry$exports, c("foo"))
  expect_equal(entry$path, "/test.arl")
})

# Export management tests
test_that("update_exports() requires valid name", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)

  expect_error(
    registry$update_exports(123, c("bar")),
    "module name must be a single string"
  )
})

test_that("update_exports() fails for non-existent module", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)

  expect_error(
    registry$update_exports("nonexistent", c("bar")),
    "module 'nonexistent' is not loaded"
  )
})

test_that("update_exports() updates exports list", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  registry$register("test-mod", mod_env, c("foo"))
  entry <- registry$update_exports("test-mod", c("foo", "bar", "baz"))

  expect_equal(entry$exports, c("foo", "bar", "baz"))
})

test_that("update_exports() preserves environment and path", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  registry$register("test-mod", mod_env, c("foo"), path = "/test.arl")
  entry <- registry$update_exports("test-mod", c("bar"))

  expect_identical(entry$env, mod_env)
  expect_equal(entry$path, "/test.arl")
})

test_that("update_exports() maintains locking", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  registry$register("test-mod", mod_env, c("foo"))
  entry <- registry$update_exports("test-mod", c("bar"))

  expect_true(environmentIsLocked(entry))
  reg_env <- arl_env$module_registry_env(create = FALSE)
  expect_true(bindingIsLocked("test-mod", reg_env))
})

# Path aliasing tests
test_that("alias() requires valid path and name", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)

  expect_error(
    registry$alias(123, "test"),
    "alias requires path and name as single strings"
  )
  expect_error(
    registry$alias("/path", 123),
    "alias requires path and name as single strings"
  )
  expect_error(
    registry$alias(c("a", "b"), "test"),
    "alias requires path and name as single strings"
  )
})

test_that("alias() fails for non-existent module", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)

  expect_error(
    registry$alias("/path/to/test.arl", "nonexistent"),
    "module 'nonexistent' is not loaded"
  )
})

test_that("alias() creates path lookup", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  registry$register("test-mod", mod_env, c("foo"))
  registry$alias("/path/to/test.arl", "test-mod")

  # Can retrieve by path
  entry_by_path <- registry$get("/path/to/test.arl")
  entry_by_name <- registry$get("test-mod")

  expect_identical(entry_by_path, entry_by_name)
})

test_that("alias() is idempotent for same module", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  registry$register("test-mod", mod_env, c("foo"))
  registry$alias("/path/to/test.arl", "test-mod")

  # Second alias call should succeed
  expect_silent(registry$alias("/path/to/test.arl", "test-mod"))
})

test_that("alias() prevents conflicting paths", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env1 <- new.env()
  mod_env2 <- new.env()

  registry$register("mod1", mod_env1, c("foo"))
  registry$register("mod2", mod_env2, c("bar"))
  registry$alias("/path/test.arl", "mod1")

  expect_error(
    registry$alias("/path/test.arl", "mod2"),
    "path '/path/test.arl' is already bound to a different module"
  )
})

test_that("alias() locks the path binding", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  registry$register("test-mod", mod_env, c("foo"))
  registry$alias("/path/to/test.arl", "test-mod")

  reg_env <- arl_env$module_registry_env(create = FALSE)
  expect_true(bindingIsLocked("/path/to/test.arl", reg_env))
})

test_that("exists() works with aliased paths", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  registry$register("test-mod", mod_env, c("foo"))
  registry$alias("/path/to/test.arl", "test-mod")

  expect_true(registry$exists("/path/to/test.arl"))
})

# Module attachment tests
test_that("attach() fails for missing module", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)

  expect_error(
    registry$attach("nonexistent"),
    "module 'nonexistent' is not loaded"
  )
})

test_that("attach() makes exports accessible via proxy", {
  test_env <- new.env(parent = emptyenv())
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()
  mod_env$foo <- 42
  mod_env$bar <- "test"

  registry$register("test-mod", mod_env, c("foo", "bar"))
  registry$attach("test-mod")

  # Proxy-based: values accessible via get() with inherits
  expect_equal(get("foo", envir = arl_env$env), 42)
  expect_equal(get("bar", envir = arl_env$env), "test")
})

test_that("attach() handles macro exports via proxy", {
  test_env <- new.env(parent = emptyenv())
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env(parent = emptyenv())

  # Create a macro in the module's macro registry and as regular binding
  mod_macro_registry <- arl_env$macro_registry_env(mod_env, create = TRUE)
  mod_macro_registry$my_macro <- function(x) x
  mod_env$my_macro <- function(x) x

  registry$register("test-mod", mod_env, c("my_macro"))
  registry$attach("test-mod")

  # Macro should be accessible in the proxy's macro registry
  proxy <- parent.env(arl_env$env)
  proxy_macro_registry <- get0(".__macros", envir = proxy, inherits = FALSE)
  expect_true(!is.null(proxy_macro_registry))
  expect_true(is.function(get("my_macro", envir = proxy_macro_registry)))
})

test_that("attach() errors on missing export", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()
  mod_env$foo <- 42

  registry$register("test-mod", mod_env, c("foo", "missing"))

  expect_error(
    registry$attach("test-mod"),
    "module 'test-mod' does not export 'missing'"
  )
})

test_that("attach_into() fails for missing module", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  target <- new.env()

  expect_error(
    registry$attach_into("nonexistent", target),
    "module 'nonexistent' is not loaded"
  )
})

test_that("attach_into() makes exports accessible via proxy", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()
  mod_env$foo <- 42
  mod_env$bar <- "test"
  target <- new.env(parent = emptyenv())

  registry$register("test-mod", mod_env, c("foo", "bar"))
  registry$attach_into("test-mod", target)

  # Proxy-based: values accessible via get() with inherits
  expect_equal(get("foo", envir = target), 42)
  expect_equal(get("bar", envir = target), "test")
})

test_that("attach_into() handles macros via proxy's macro registry", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env(parent = emptyenv())
  target <- new.env(parent = emptyenv())

  # Create a macro in the module's macro registry and also as regular binding
  mod_macro_registry <- arl_env$macro_registry_env(mod_env, create = TRUE)
  mod_macro_registry$my_macro <- function(x) x
  mod_env$my_macro <- function(x) x

  registry$register("test-mod", mod_env, c("my_macro"))
  registry$attach_into("test-mod", target)

  # Macro should be accessible in proxy's macro registry
  proxy <- parent.env(target)
  proxy_macro_registry <- get0(".__macros", envir = proxy, inherits = FALSE)
  expect_true(!is.null(proxy_macro_registry))
  # Active binding in proxy macro registry should return the macro
  expect_true(is.function(get("my_macro", envir = proxy_macro_registry)))
})

test_that("attach_into() is idempotent for same module", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env(parent = emptyenv())
  mod_env$foo <- 42
  target <- new.env(parent = emptyenv())

  registry$register("test-mod", mod_env, c("foo"))
  registry$attach_into("test-mod", target)
  # Second call should be a no-op (no duplicate proxy)
  registry$attach_into("test-mod", target)

  # Count proxies in chain
  proxy_count <- 0L
  p <- parent.env(target)
  while (!identical(p, emptyenv())) {
    if (isTRUE(get0(".__import_proxy", envir = p, inherits = FALSE))) {
      proxy_count <- proxy_count + 1L
    }
    p <- parent.env(p)
  }
  expect_equal(proxy_count, 1L)
})

test_that("attach_into() errors on missing export", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()
  mod_env$foo <- 42
  target <- new.env()

  registry$register("test-mod", mod_env, c("foo", "missing"))

  expect_error(
    registry$attach_into("test-mod", target),
    "module 'test-mod' does not export 'missing'"
  )
})

# Cleanup tests
test_that("unregister() requires valid name", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)

  expect_error(
    registry$unregister(123),
    "module name must be a single string"
  )
})

test_that("unregister() removes module from registry", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)
  mod_env <- new.env()

  registry$register("test-mod", mod_env, c("foo"))
  expect_true(registry$exists("test-mod"))

  registry$unregister("test-mod")
  expect_false(registry$exists("test-mod"))
})

test_that("unregister() is safe for non-existent modules", {
  test_env <- new.env()
  arl_env <- arl:::Env$new(test_env)
  registry <- arl:::ModuleRegistry$new(arl_env)

  # Should not error
  expect_silent(registry$unregister("nonexistent"))
})

# ============================================================================
# Namespace nodes (hierarchical module names)
# ============================================================================

test_that("namespace? predicate", {
  engine <- make_engine()
  ns <- arl:::make_namespace_node("collections")
  expect_true(inherits(ns, "arl_namespace"))
  expect_true(engine$eval_text("(namespace? ns)", env = list2env(list(ns = ns), parent = engine$get_env())))
  expect_false(engine$eval_text("(namespace? 42)"))
})

test_that("make_namespace_node creates locked env with prefix", {
  ns <- arl:::make_namespace_node("collections")
  expect_true(environmentIsLocked(ns))
  expect_equal(get(".__namespace_prefix", envir = ns), "collections")
  expect_true(inherits(ns, "arl_namespace"))
})

test_that("module-ref on namespace node returns module if registered", {
  engine <- make_engine()
  env <- engine$get_env()
  # Create a module with a hierarchical name using a string literal
  engine$eval_text('
    (module "collections/sorted-set"
      (export make-set)
      (define make-set (lambda () (list))))
  ', env = env)
  # Create namespace node and test module-ref
  ns <- arl:::make_namespace_node("collections")
  test_env <- new.env(parent = env)
  assign("ns", ns, envir = test_env)
  result <- engine$eval_text("(module-ref ns sorted-set)", env = test_env)
  expect_true(is.environment(result))
})