;;;; The prelude's byte predicates, parse-i64, and the two number helpers.
;;;;
;;;; The cases are chosen so a wrong implementation fails one: a prefix longer
;;;; than the string (which must answer false, not trap), the empty prefix and
;;;; the whole string as its own prefix, a prefix that matches at the wrong
;;;; end, and for parse-i64 every shape strtoll answers 0 for — "", "abc",
;;;; "12x", "-" — each of which a caller could not tell from a real 0.

(defn show-bool [b bool] ()
  (print (if b "t" "f")))

(defn main [] i32
  (show-bool (bytes=? (bytes "abc") (bytes "abc")))        ; t
  (show-bool (bytes=? (bytes "abc") (bytes "abd")))        ; f  same length
  (show-bool (bytes=? (bytes "abc") (bytes "ab")))         ; f  prefix, not equal
  (show-bool (bytes=? (bytes "") (bytes "")))              ; t
  (println "")

  (show-bool (starts-with? (bytes "hello") (bytes "hel"))) ; t
  (show-bool (starts-with? (bytes "hello") (bytes "llo"))) ; f  matches the end
  (show-bool (starts-with? (bytes "hi") (bytes "hiya")))   ; f  longer, no trap
  (show-bool (starts-with? (bytes "hello") (bytes "")))    ; t
  (show-bool (starts-with? (bytes "hello") (bytes "hello"))) ; t
  (println "")

  (show-bool (ends-with? (bytes "hello") (bytes "llo")))   ; t
  (show-bool (ends-with? (bytes "hello") (bytes "hel")))   ; f  matches the start
  (show-bool (ends-with? (bytes "hi") (bytes "hiya")))     ; f  longer, no trap
  (show-bool (ends-with? (bytes "hello") (bytes "")))      ; t
  (show-bool (ends-with? (bytes "hello") (bytes "hello"))) ; t
  (println "")

  ;; First occurrence, and None for a byte that is not there.
  (print (match (index-of (bytes "banana") \a) (Some i) i None -1))
  (print " ")
  (print (match (index-of (bytes "banana") \z) (Some i) i None -1))
  (print " ")
  (print (match (index-of (bytes "") \a) (Some i) i None -1))
  (println "")

  ;; Accepted.
  (print (match (parse-i64 (bytes "0")) (Some v) v None -999)) (print " ")
  (print (match (parse-i64 (bytes "42")) (Some v) v None -999)) (print " ")
  (print (match (parse-i64 (bytes "-42")) (Some v) v None -999)) (print " ")
  (print (match (parse-i64 (bytes "+7")) (Some v) v None -999)) (print " ")
  (print (match (parse-i64 (bytes "9007199254740993")) (Some v) v None -999))
  (println "")
  ;; Refused. Each of these is a 0 out of strtoll, which is the point.
  (print (match (parse-i64 (bytes "")) (Some v) v None -999)) (print " ")
  (print (match (parse-i64 (bytes "abc")) (Some v) v None -999)) (print " ")
  (print (match (parse-i64 (bytes "12x")) (Some v) v None -999)) (print " ")
  (print (match (parse-i64 (bytes "-")) (Some v) v None -999)) (print " ")
  (print (match (parse-i64 (bytes " 1")) (Some v) v None -999))
  (println "")

  (print (sign-f32 3.5)) (print " ")
  (print (sign-f32 -3.5)) (print " ")
  (print (sign-f32 0.0))
  (println "")

  ;; t = 1.0 must return b exactly, which a + t*(b - a) does not always do.
  (print (lerp 0.0 10.0 0.0)) (print " ")
  (print (lerp 0.0 10.0 0.25)) (print " ")
  (print (lerp 0.0 10.0 1.0)) (print " ")
  (print (lerp 2.0 -2.0 0.5))
  (println "")

  ;; The RNG ranges, off a fixed seed, so the numbers are the sequence and not
  ;; just "something in range". An empty range answers lo and must not divide.
  (rand-seed 7)
  (dotimes [i 5]
    (when (> i 0) (print " "))
    (print (rand-i32-range 10 20)))
  (println "")
  (print (rand-i32-range 5 5)) (print " ")
  (print (rand-i32-range 5 -5))
  (println "")
  (rand-seed 7)
  (dotimes [i 3]
    (when (> i 0) (print " "))
    (print (rand-f32-range 0.0 1.0)))
  (println "")
  0)