#!/bin/awk -f
#
# Copyright © 2021 Nick Bowler
#
# Generate a mapping from a (random) integer to a list of type specifiers
# represented by struct cdecl_declspec.  Used internally by declgen to
# produce random valid declarations.
#
# License WTFPL2: Do What The Fuck You Want To Public License, version 2.
# This is free software: you are free to do what the fuck you want to.
# There is NO WARRANTY, to the extent permitted by law.

END {
  print "/*"
  if (FILENAME) {
    print " * Automatically generated by gen-typegen.awk from " FILENAME
  } else {
    print " * Automatically generated by gen-typegen.awk"
  }
  print " * Do not edit."
  print " */"
}

BEGIN {
  count = 0
}

$0 ~ /^[abcdefghijklmnopqrstuvwxyz_]/ {
  for (i = 1; i <= NF; i++) {
    sub(/_/, "", $i)
    $i = "CDECL_TYPE_" toupper($i)
  }
  specs[count++] = $0
}

END {
  print "static inline struct cdecl_declspec *"
  print "gen_raw_typespec_(unsigned type, struct cdecl_declspec *next)\n{"
  print "\tstruct cdecl_declspec *s = malloc_nofail(sizeof *s);"
  print "\t*s = (struct cdecl_declspec) { .next = next, .type = type };"
  print "\treturn s;\n}\n"

  print "static inline struct cdecl_declspec *"
  print "gen_raw_typespecs(unsigned rngval)\n{"
  print "\tswitch (rngval) {"

  for (i = 0; i < count; i++) {
    print "\tcase " i ":"
    $0 = specs[i]

    for (j = 1; j <= NF; j++) {
      prefix = j == 1 ? "return" : "";

      printf "\t\t%6s gen_raw_typespec_(%s,\n", prefix, $j
    }
    printf "\t\t%25sNULL%.*s;\n", "", NF, "))))))))"
  }
  print "\tdefault:\n\t\tassert(0);\n\t}"
  print "}\n"
  print "enum { GEN_TOTAL_TYPES = " count " };"
}