;; lib/prolog/tests/atoms.sx — type predicates + string/atom built-ins

(define pl-at-test-count 0)
(define pl-at-test-pass 0)
(define pl-at-test-fail 0)
(define pl-at-test-failures (list))

(define
  pl-at-test!
  (fn
    (name got expected)
    (begin
      (set! pl-at-test-count (+ pl-at-test-count 1))
      (if
        (= got expected)
        (set! pl-at-test-pass (+ pl-at-test-pass 1))
        (begin
          (set! pl-at-test-fail (+ pl-at-test-fail 1))
          (append!
            pl-at-test-failures
            (str name "\n    expected: " expected "\n    got:      " got)))))))

(define
  pl-at-goal
  (fn
    (src env)
    (pl-instantiate (nth (first (pl-parse (str "g :- " src "."))) 2) env)))

(define pl-at-db (pl-mk-db))

;; ── var/1 + nonvar/1 ──

(pl-at-test!
  "var(X) for unbound var"
  (pl-solve-once! pl-at-db (pl-at-goal "var(X)" {}) (pl-mk-trail))
  true)
(pl-at-test!
  "var(foo) fails"
  (pl-solve-once! pl-at-db (pl-at-goal "var(foo)" {}) (pl-mk-trail))
  false)
(pl-at-test!
  "nonvar(foo) succeeds"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "nonvar(foo)" {})
    (pl-mk-trail))
  true)
(pl-at-test!
  "nonvar(X) for unbound var fails"
  (pl-solve-once! pl-at-db (pl-at-goal "nonvar(X)" {}) (pl-mk-trail))
  false)

;; ── atom/1 ──

(pl-at-test!
  "atom(foo) succeeds"
  (pl-solve-once! pl-at-db (pl-at-goal "atom(foo)" {}) (pl-mk-trail))
  true)
(pl-at-test!
  "atom([]) succeeds"
  (pl-solve-once! pl-at-db (pl-at-goal "atom([])" {}) (pl-mk-trail))
  true)
(pl-at-test!
  "atom(42) fails"
  (pl-solve-once! pl-at-db (pl-at-goal "atom(42)" {}) (pl-mk-trail))
  false)
(pl-at-test!
  "atom(f(x)) fails"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "atom(f(x))" {})
    (pl-mk-trail))
  false)

;; ── number/1 + integer/1 ──

(pl-at-test!
  "number(42) succeeds"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "number(42)" {})
    (pl-mk-trail))
  true)
(pl-at-test!
  "number(foo) fails"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "number(foo)" {})
    (pl-mk-trail))
  false)
(pl-at-test!
  "integer(7) succeeds"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "integer(7)" {})
    (pl-mk-trail))
  true)

;; ── compound/1 + callable/1 + atomic/1 ──

(pl-at-test!
  "compound(f(x)) succeeds"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "compound(f(x))" {})
    (pl-mk-trail))
  true)
(pl-at-test!
  "compound(foo) fails"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "compound(foo)" {})
    (pl-mk-trail))
  false)
(pl-at-test!
  "callable(foo) succeeds"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "callable(foo)" {})
    (pl-mk-trail))
  true)
(pl-at-test!
  "callable(f(x)) succeeds"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "callable(f(x))" {})
    (pl-mk-trail))
  true)
(pl-at-test!
  "callable(42) fails"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "callable(42)" {})
    (pl-mk-trail))
  false)
(pl-at-test!
  "atomic(foo) succeeds"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "atomic(foo)" {})
    (pl-mk-trail))
  true)
(pl-at-test!
  "atomic(42) succeeds"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "atomic(42)" {})
    (pl-mk-trail))
  true)
(pl-at-test!
  "atomic(f(x)) fails"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "atomic(f(x))" {})
    (pl-mk-trail))
  false)

;; ── is_list/1 ──

(pl-at-test!
  "is_list([]) succeeds"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "is_list([])" {})
    (pl-mk-trail))
  true)
(pl-at-test!
  "is_list([1,2,3]) succeeds"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "is_list([1,2,3])" {})
    (pl-mk-trail))
  true)
(pl-at-test!
  "is_list(foo) fails"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "is_list(foo)" {})
    (pl-mk-trail))
  false)

;; ── atom_length/2 ──

(define pl-at-env-al {})
(pl-solve-once!
  pl-at-db
  (pl-at-goal "atom_length(hello, N)" pl-at-env-al)
  (pl-mk-trail))
(pl-at-test!
  "atom_length(hello, N) -> N=5"
  (pl-num-val (pl-walk-deep (dict-get pl-at-env-al "N")))
  5)
(pl-at-test!
  "atom_length empty atom"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "atom_length('', 0)" {})
    (pl-mk-trail))
  true)

;; ── atom_concat/3 ──

(define pl-at-env-ac {})
(pl-solve-once!
  pl-at-db
  (pl-at-goal "atom_concat(foo, bar, X)" pl-at-env-ac)
  (pl-mk-trail))
(pl-at-test!
  "atom_concat(foo, bar, X) -> X=foobar"
  (pl-atom-name (pl-walk-deep (dict-get pl-at-env-ac "X")))
  "foobar")

(pl-at-test!
  "atom_concat(foo, bar, foobar) check"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "atom_concat(foo, bar, foobar)" {})
    (pl-mk-trail))
  true)
(pl-at-test!
  "atom_concat(foo, bar, foobaz) fails"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "atom_concat(foo, bar, foobaz)" {})
    (pl-mk-trail))
  false)

(define pl-at-env-ac2 {})
(pl-solve-once!
  pl-at-db
  (pl-at-goal "atom_concat(foo, Y, foobar)" pl-at-env-ac2)
  (pl-mk-trail))
(pl-at-test!
  "atom_concat(foo, Y, foobar) -> Y=bar"
  (pl-atom-name (pl-walk-deep (dict-get pl-at-env-ac2 "Y")))
  "bar")

;; ── atom_chars/2 ──

(define pl-at-env-ach {})
(pl-solve-once!
  pl-at-db
  (pl-at-goal "atom_chars(cat, Cs)" pl-at-env-ach)
  (pl-mk-trail))
(pl-at-test!
  "atom_chars(cat, Cs) -> Cs=[c,a,t]"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "atom_chars(cat, [c,a,t])" {})
    (pl-mk-trail))
  true)

(define pl-at-env-ach2 {})
(pl-solve-once!
  pl-at-db
  (pl-at-goal "atom_chars(A, [h,i])" pl-at-env-ach2)
  (pl-mk-trail))
(pl-at-test!
  "atom_chars(A, [h,i]) -> A=hi"
  (pl-atom-name (pl-walk-deep (dict-get pl-at-env-ach2 "A")))
  "hi")

;; ── char_code/2 ──

(define pl-at-env-cc {})
(pl-solve-once!
  pl-at-db
  (pl-at-goal "char_code(a, N)" pl-at-env-cc)
  (pl-mk-trail))
(pl-at-test!
  "char_code(a, N) -> N=97"
  (pl-num-val (pl-walk-deep (dict-get pl-at-env-cc "N")))
  97)

(define pl-at-env-cc2 {})
(pl-solve-once!
  pl-at-db
  (pl-at-goal "char_code(C, 65)" pl-at-env-cc2)
  (pl-mk-trail))
(pl-at-test!
  "char_code(C, 65) -> C='A'"
  (pl-atom-name (pl-walk-deep (dict-get pl-at-env-cc2 "C")))
  "A")

;; ── number_codes/2 ──

(pl-at-test!
  "number_codes(42, [52,50])"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "number_codes(42, [52,50])" {})
    (pl-mk-trail))
  true)

;; ── number_chars/2 ──

(pl-at-test!
  "number_chars(42, ['4','2'])"
  (pl-solve-once!
    pl-at-db
    (pl-at-goal "number_chars(42, ['4','2'])" {})
    (pl-mk-trail))
  true)

(define pl-atom-tests-run! (fn () {:failed pl-at-test-fail :passed pl-at-test-pass :total pl-at-test-count :failures pl-at-test-failures}))