/*
Language: SAS
Author: Mauricio Caceres <mauricio.caceres.bravo@gmail.com>
Description: Syntax Highlighting for SAS
*/

function sas(hljs) {
  // Data step and PROC SQL statements
  const SAS_KEYWORDS =
    'do if then else end until while ' +
    '' +
    'abort array attrib by call cards cards4 catname continue ' +
    'datalines datalines4 delete delim delimiter display dm drop ' +
    'endsas error file filename footnote format goto in infile ' +
    'informat input keep label leave length libname link list ' +
    'lostcard merge missing modify options output out page put ' +
    'redirect remove rename replace retain return select set skip ' +
    'startsas stop title update waitsas where window x systask ' +
    '' +
    'add and alter as cascade check create delete describe ' +
    'distinct drop foreign from group having index insert into in ' +
    'key like message modify msgtype not null on or order primary ' +
    'references reset restrict select set table unique update ' +
    'validate view where';

  // Built-in SAS functions
  const SAS_FUN =
    'abs|addr|airy|arcos|arsin|atan|attrc|attrn|band|' +
    'betainv|blshift|bnot|bor|brshift|bxor|byte|cdf|ceil|' +
    'cexist|cinv|close|cnonct|collate|compbl|compound|' +
    'compress|cos|cosh|css|curobs|cv|daccdb|daccdbsl|' +
    'daccsl|daccsyd|dacctab|dairy|date|datejul|datepart|' +
    'datetime|day|dclose|depdb|depdbsl|depdbsl|depsl|' +
    'depsl|depsyd|depsyd|deptab|deptab|dequote|dhms|dif|' +
    'digamma|dim|dinfo|dnum|dopen|doptname|doptnum|dread|' +
    'dropnote|dsname|erf|erfc|exist|exp|fappend|fclose|' +
    'fcol|fdelete|fetch|fetchobs|fexist|fget|fileexist|' +
    'filename|fileref|finfo|finv|fipname|fipnamel|' +
    'fipstate|floor|fnonct|fnote|fopen|foptname|foptnum|' +
    'fpoint|fpos|fput|fread|frewind|frlen|fsep|fuzz|' +
    'fwrite|gaminv|gamma|getoption|getvarc|getvarn|hbound|' +
    'hms|hosthelp|hour|ibessel|index|indexc|indexw|input|' +
    'inputc|inputn|int|intck|intnx|intrr|irr|jbessel|' +
    'juldate|kurtosis|lag|lbound|left|length|lgamma|' +
    'libname|libref|log|log10|log2|logpdf|logpmf|logsdf|' +
    'lowcase|max|mdy|mean|min|minute|mod|month|mopen|' +
    'mort|n|netpv|nmiss|normal|note|npv|open|ordinal|' +
    'pathname|pdf|peek|peekc|pmf|point|poisson|poke|' +
    'probbeta|probbnml|probchi|probf|probgam|probhypr|' +
    'probit|probnegb|probnorm|probt|put|putc|putn|qtr|' +
    'quote|ranbin|rancau|ranexp|rangam|range|rank|rannor|' +
    'ranpoi|rantbl|rantri|ranuni|repeat|resolve|reverse|' +
    'rewind|right|round|saving|scan|sdf|second|sign|' +
    'sin|sinh|skewness|soundex|spedis|sqrt|std|stderr|' +
    'stfips|stname|stnamel|substr|sum|symget|sysget|' +
    'sysmsg|sysprod|sysrc|system|tan|tanh|time|timepart|' +
    'tinv|tnonct|today|translate|tranwrd|trigamma|' +
    'trim|trimn|trunc|uniform|upcase|uss|var|varfmt|' +
    'varinfmt|varlabel|varlen|varname|varnum|varray|' +
    'varrayx|vartype|verify|vformat|vformatd|vformatdx|' +
    'vformatn|vformatnx|vformatw|vformatwx|vformatx|' +
    'vinarray|vinarrayx|vinformat|vinformatd|vinformatdx|' +
    'vinformatn|vinformatnx|vinformatw|vinformatwx|' +
    'vinformatx|vlabel|vlabelx|vlength|vlengthx|vname|' +
    'vnamex|vtype|vtypex|weekday|year|yyq|zipfips|zipname|' +
    'zipnamel|zipstate';

  // Built-in macro functions
  const SAS_MACRO_FUN =
    'bquote|nrbquote|cmpres|qcmpres|compstor|' +
    'datatyp|display|do|else|end|eval|global|goto|' +
    'if|index|input|keydef|label|left|length|let|' +
    'local|lowcase|macro|mend|nrbquote|nrquote|' +
    'nrstr|put|qcmpres|qleft|qlowcase|qscan|' +
    'qsubstr|qsysfunc|qtrim|quote|qupcase|scan|str|' +
    'substr|superq|syscall|sysevalf|sysexec|sysfunc|' +
    'sysget|syslput|sysprod|sysrc|sysrput|then|to|' +
    'trim|unquote|until|upcase|verify|while|window';

  return {
    name: 'SAS',
    case_insensitive: true, // SAS is case-insensitive
    keywords: {
      literal:
        'null missing _all_ _automatic_ _character_ _infile_ ' +
        '_n_ _name_ _null_ _numeric_ _user_ _webout_',
      meta:
        SAS_KEYWORDS
    },
    contains: [
      {
        // Distinct highlight for proc <proc>, data, run, quit
        className: 'keyword',
        begin: /^\s*(proc [\w\d_]+|data|run|quit)[\s;]/
      },
      {
        // Macro variables
        className: 'variable',
        begin: /&[a-zA-Z_&][a-zA-Z0-9_]*\.?/
      },
      {
        // Special emphasis for datalines|cards
        className: 'emphasis',
        begin: /^\s*datalines|cards.*;/,
        end: /^\s*;\s*$/
      },
      { // Built-in macro variables take precedence
        className: 'built_in',
        begin: '%(' + SAS_MACRO_FUN + ')'
      },
      {
        // User-defined macro functions highlighted after
        className: 'name',
        begin: /%[a-zA-Z_][a-zA-Z_0-9]*/
      },
      {
        className: 'meta',
        begin: '[^%](' + SAS_FUN + ')[\(]'
      },
      {
        className: 'string',
        variants: [
          hljs.APOS_STRING_MODE,
          hljs.QUOTE_STRING_MODE
        ]
      },
      hljs.COMMENT('\\*', ';'),
      hljs.C_BLOCK_COMMENT_MODE
    ]
  };
}

module.exports = sas;