Ben / Nujel

;; Nujel - Copyright (C) 2020-2021 - Benjamin Vincent Schulenburg
;; This project uses the MIT license, a copy should be included under /LICENSE

[def repl/executable-name "nujel"]
[def repl/parse-args/eval-next #f]
[def repl/parse-args/run-repl #t]
[def repl/options @[]]
[def repl/option-map @[]]

[defn repl/exception-handler [error]
  [display/error error]]

[def repl/history #nil]

[defn repl/prompt []
  "> "]

[defn repl/wasm [line]
  "Evaluate LINE in the wasm context"
  [try repl/exception-handler
       [eval-in root-closure [cons do [read line]]]]]

[defn repl/cmd/raw [ctx line]
  [when [nil? line]
    [display "Bye!\r\n"]
    [exit 0]]
  [def expr [read line]]
  [when [equal? '[] expr]
    [print "\r"]
    [return]]
  [def result [eval-in ctx [cons do expr]]]
  [set! repl/history [cons line repl/history]]
  [println [if [nil? result] "" [str/write result]]]]

[defn repl/cmd [ctx]
  [def buf ""]
  [def line ""]
  [while [!= line "[/cmd]\n"]
    [set! buf [cat buf line]]
    [set! line [readline]]]
  [def expr [cons do [read buf]]]
  [set! repl/history [cons buf repl/history]]
  [def result [eval-in ctx expr]]
  [println [if [nil? result] "" [str/write result]]]]

[defn repl/readline [ctx]
  [def line [readline [repl/prompt]]]
  [if [== line "[cmd]\n"]
      [repl/cmd ctx]
      [repl/cmd/raw ctx line]]]

[defn repl []
  [while #t
    [try repl/exception-handler
         [repl/readline root-closure]]]]

[defn repl/print-help []
  [println [cat [ansi-rainbow "Nujel"] " - A Lisp dialect for games.\n"]]
  [println [cat [ansi-green "Usage:"] " nujel [options] [command_string | file]"]]
  [println [cat "\nLow-level options - for work on the runtime itself"]]
  [println [cat "  " [ansi-yellow "v"] " - be verbose"]]
  [println [cat "\nHigh-level options - for working with/on Nujel code"]]
  [println [cat "  " [ansi-blue "x"] " - Run the expression following this argument directly"]]
  [println [cat "  " [ansi-blue "h"] " - Print this help screen"]]
  [println [cat "\nLong options - for working with/on Nujel code"]]
  [println [cat "  " [ansi-blue "no-color"] " - Disable ANSI color"]]
  [println [cat "  " [ansi-blue "color   "] " - Enable ANSI color"]]]

[tree/set! repl/option-map 'h
           [fn [option]
               [repl/print-help]
               [set! repl/parse-args/run-repl #f]]]
[tree/set! repl/option-map 'no-color
           [fn [option]
               [set! ansi/disabled ""]]]
[tree/set! repl/option-map 'color
           [fn [option]
               [set! ansi/disabled #f]]]
[tree/set! repl/option-map 'x
           [fn [option]
               [set! repl/parse-args/eval-next #t]
               [set! repl/parse-args/run-repl #f]]]
[tree/set! repl/option-map :default
           [fn [option]
               [tree/set! repl/options option #t]]]

[defn repl/parse-option [option]
  [[or [ref repl/option-map option]
       [ref repl/option-map :default]] option]]

[defn repl/parse-options [options]
  [if [== [char-at options 0] #\-]
      [repl/parse-option [string->keyword [cut options 1]]]
      [for-each [map [split options ""] str->sym] repl/parse-option]]]

[defn repl/parse-arg [arg]
  [cond [repl/parse-args/eval-next [try display/error
                                        [eval-in root-closure [cons do [read arg]]]
                                        [set! repl/parse-args/eval-next #f]]]
        [[== [char-at arg 0] #\-] [repl/parse-options [string/cut arg 1]]]
        [#t [try display/error
                 [file/eval arg]]
            [set! repl/parse-args/run-repl #f]]]]

[defn repl/parse-args [args]
  [if args
      [do [repl/parse-arg [car args]]
          [repl/parse-args [cdr args]]]
      repl/parse-args/run-repl]]

[defn repl/init/wasm [args]
  [println [cat [ansi-rainbow "Nujel"] " heißt euch willkommen!"]]]

[defn repl/init/bin [args]
  [try repl/exception-handler
       [set! repl/executable-name [car args]]
       [when [repl/parse-args [cdr args]] [repl]]]]

[defn repl/init args
  [if [== System/Architecture 'wasm]
      [repl/init/wasm args]
      [repl/init/bin args]]]