runtime/syntax/syntax_converter.go

   1 package main
   2
   3 import (
   4         "fmt"
   5         "io/ioutil"
   6         "os"
   7         "regexp"
   8         "strings"
   9 )
  10
  11 type SingleRule struct {
  12         color string
  13         regex string
  14 }
  15
  16 type MultiRule struct {
  17         color string
  18         start string
  19         end   string
  20 }
  21
  22 // JoinRule takes a syntax rule (which can be multiple regular expressions)
  23 // and joins it into one regular expression by ORing everything together
  24 func JoinRule(rule string) string {
  25         split := strings.Split(rule, `" "`)
  26         joined := strings.Join(split, "|")
  27         return joined
  28 }
  29
  30 func parseFile(text, filename string) (filetype, syntax, header string, rules []interface{}) {
  31         lines := strings.Split(text, "\n")
  32
  33         // Regex for parsing syntax statements
  34         syntaxParser := regexp.MustCompile(`syntax "(.*?)"\s+"(.*)"+`)
  35         // Regex for parsing header statements
  36         headerParser := regexp.MustCompile(`header "(.*)"`)
  37
  38         // Regex for parsing standard syntax rules
  39         ruleParser := regexp.MustCompile(`color (.*?)\s+(?:\((.+?)?\)\s+)?"(.*)"`)
  40         // Regex for parsing syntax rules with start="..." end="..."
  41         ruleStartEndParser := regexp.MustCompile(`color (.*?)\s+(?:\((.+?)?\)\s+)?start="(.*)"\s+end="(.*)"`)
  42
  43         for lineNum, line := range lines {
  44                 line = strings.TrimSpace(line)
  45                 if line == "" {
  46                         continue
  47                 }
  48                 if strings.HasPrefix(line, "#") {
  49                         continue
  50                 }
  51                 if strings.HasPrefix(line, "syntax") {
  52                         syntaxMatches := syntaxParser.FindSubmatch([]byte(line))
  53                         if len(syntaxMatches) == 3 {
  54                                 filetype = string(syntaxMatches[1])
  55                                 syntax = JoinRule(string(syntaxMatches[2]))
  56                         } else {
  57                                 fmt.Println(filename, lineNum, "Syntax statement is not valid: "+line)
  58                                 continue
  59                         }
  60                 }
  61                 if strings.HasPrefix(line, "header") {
  62                         // Header statement
  63                         headerMatches := headerParser.FindSubmatch([]byte(line))
  64                         if len(headerMatches) == 2 {
  65                                 header = JoinRule(string(headerMatches[1]))
  66                         } else {
  67                                 fmt.Println(filename, lineNum, "Header statement is not valid: "+line)
  68                                 continue
  69                         }
  70                 }
  71
  72                 // Syntax rule, but it could be standard or start-end
  73                 if ruleParser.MatchString(line) {
  74                         // Standard syntax rule
  75                         // Parse the line
  76                         submatch := ruleParser.FindSubmatch([]byte(line))
  77                         var color string
  78                         var regexStr string
  79                         var flags string
  80                         if len(submatch) == 4 {
  81                                 // If len is 4 then the user specified some additional flags to use
  82                                 color = string(submatch[1])
  83                                 flags = string(submatch[2])
  84                                 if flags != "" {
  85                                         regexStr = "(?" + flags + ")" + JoinRule(string(submatch[3]))
  86                                 } else {
  87                                         regexStr = JoinRule(string(submatch[3]))
  88                                 }
  89                         } else if len(submatch) == 3 {
  90                                 // If len is 3, no additional flags were given
  91                                 color = string(submatch[1])
  92                                 regexStr = JoinRule(string(submatch[2]))
  93                         } else {
  94                                 // If len is not 3 or 4 there is a problem
  95                                 fmt.Println(filename, lineNum, "Invalid statement: "+line)
  96                                 continue
  97                         }
  98
  99                         rules = append(rules, SingleRule{color, regexStr})
 100                 } else if ruleStartEndParser.MatchString(line) {
 101                         // Start-end syntax rule
 102                         submatch := ruleStartEndParser.FindSubmatch([]byte(line))
 103                         var color string
 104                         var start string
 105                         var end string
 106                         // Use m and s flags by default
 107                         if len(submatch) == 5 {
 108                                 // If len is 5 the user provided some additional flags
 109                                 color = string(submatch[1])
 110                                 start = string(submatch[3])
 111                                 end = string(submatch[4])
 112                         } else if len(submatch) == 4 {
 113                                 // If len is 4 the user did not provide additional flags
 114                                 color = string(submatch[1])
 115                                 start = string(submatch[2])
 116                                 end = string(submatch[3])
 117                         } else {
 118                                 // If len is not 4 or 5 there is a problem
 119                                 fmt.Println(filename, lineNum, "Invalid statement: "+line)
 120                                 continue
 121                         }
 122
 123                         // rules[color] = "(?" + flags + ")" + "(" + start + ").*?(" + end + ")"
 124                         rules = append(rules, MultiRule{color, start, end})
 125                 }
 126         }
 127
 128         return
 129 }
 130
 131 func generateFile(filetype, syntax, header string, rules []interface{}) string {
 132         output := ""
 133
 134         output += fmt.Sprintf("filetype: %s\n\n", filetype)
 135         output += fmt.Sprintf("detect: \n    filename: \"%s\"\n", strings.Replace(strings.Replace(syntax, "\\", "\\\\", -1), "\"", "\\\"", -1))
 136
 137         if header != "" {
 138                 output += fmt.Sprintf("    header: \"%s\"\n", strings.Replace(strings.Replace(header, "\\", "\\\\", -1), "\"", "\\\"", -1))
 139         }
 140
 141         output += "\nrules:\n"
 142
 143         for _, r := range rules {
 144                 if rule, ok := r.(SingleRule); ok {
 145                         output += fmt.Sprintf("    - %s: \"%s\"\n", rule.color, strings.Replace(strings.Replace(rule.regex, "\\", "\\\\", -1), "\"", "\\\"", -1))
 146                 } else if rule, ok := r.(MultiRule); ok {
 147                         output += fmt.Sprintf("    - %s:\n", rule.color)
 148                         output += fmt.Sprintf("        start: \"%s\"\n", strings.Replace(strings.Replace(rule.start, "\\", "\\\\", -1), "\"", "\\\"", -1))
 149                         output += fmt.Sprintf("        end: \"%s\"\n", strings.Replace(strings.Replace(rule.end, "\\", "\\\\", -1), "\"", "\\\"", -1))
 150                         output += fmt.Sprintf("        rules: []\n\n")
 151                 }
 152         }
 153
 154         return output
 155 }
 156
 157 func main() {
 158         if len(os.Args) < 2 {
 159                 fmt.Println("no args")
 160                 return
 161         }
 162
 163         data, _ := ioutil.ReadFile(os.Args[1])
 164         fmt.Print(generateFile(parseFile(string(data), os.Args[1])))
 165 }