src/markdown.nit

   1 # This file is part of NIT ( http://www.nitlanguage.org ).
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License");
   4 # you may not use this file except in compliance with the License.
   5 # You may obtain a copy of the License at
   6 #
   7 #     http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 # See the License for the specific language governing permissions and
  13 # limitations under the License.
  14
  15 # Transform Nit verbatim documentation into HTML
  16 module markdown
  17
  18 import parser
  19 import html
  20
  21 # The class that does the convertion from a `ADoc` to HTML
  22 private class Doc2Mdwn
  23         var toolcontext: ToolContext
  24
  25         # The lines of the current code block, empty is no current code block
  26         var curblock = new Array[String]
  27
  28         fun work(ndoc: ADoc): HTMLTag
  29         do
  30                 var root = new HTMLTag("div")
  31                 root.add_class("nitdoc")
  32
  33                 # Indent level of the previous line
  34                 var lastindent = 0
  35
  36                 # Indent level of the current line
  37                 var indent = 0
  38
  39                 # The current element (p, li, etc.) if any
  40                 var n: nullable HTMLTag = null
  41
  42                 # The current ul element (if any)
  43                 var ul: nullable HTMLTag = null
  44
  45                 # Local variable to benefit adaptive typing
  46                 for c in ndoc.n_comment do
  47                         # Remove the starting `#`
  48                         var text = c.text.substring_from(1)
  49
  50                         # Count the number of spaces
  51                         lastindent = indent
  52                         indent = 0
  53                         while text.length > indent and text[indent] == ' ' do indent += 1
  54
  55                         # Is codeblock? Then just collect them
  56                         if indent > 4 then
  57                                 var part = text.substring_from(4)
  58                                 curblock.add(part)
  59                                 continue
  60                         end
  61
  62                         # Was a codblock just before the current line ?
  63                         close_codeblock(n or else root)
  64
  65                         # Cleanup the string
  66                         text = text.trim
  67
  68                         # The HTML node of the last line, so we know if we continue the same block
  69                         var old = n
  70
  71                         # No line or loss of indentation: reset
  72                         if text.is_empty or indent < lastindent then
  73                                 n = null
  74                                 ul = null
  75                                 if text.is_empty then continue
  76                         end
  77
  78                         # Special first word: new paragraph
  79                         if text.has_prefix("TODO") or text.has_prefix("FIXME") then
  80                                 n = new HTMLTag("p")
  81                                 root.add n
  82                                 n.add_class("todo")
  83                                 ul = null
  84                         else if text.has_prefix("REQUIRE") or text.has_prefix("Require") or text.has_prefix("ENSURE") or text.has_prefix("Ensure") then
  85                                 n = new HTMLTag("p")
  86                                 root.add n
  87                                 n.add_class("contract")
  88                                 ul = null
  89                         end
  90
  91                         # List
  92                         if text.has_prefix("* ") or text.has_prefix("- ") then
  93                                 text = text.substring_from(1).trim
  94                                 if ul == null then
  95                                         ul = new HTMLTag("ul")
  96                                         root.add ul
  97                                 end
  98                                 n = new HTMLTag("li")
  99                                 ul.add(n)
 100                         end
 101
 102                         # Nothing? then paragraph
 103                         if n == null then
 104                                 n = new HTMLTag("p")
 105                                 root.add n
 106                                 ul = null
 107                         end
 108
 109                         if old == n then
 110                                 # Because spaces and `\n` where trimmed
 111                                 n.append("\n")
 112                         end
 113
 114                         process_line(n, text)
 115
 116                         # Special case, the fist line is the synopsys and is in its own paragraph
 117                         if c == ndoc.n_comment.first then
 118                                 n.add_class("synopsys")
 119                                 n = null
 120                         end
 121                 end
 122
 123                 # If the codeblock was the last code sequence
 124                 close_codeblock(n or else root)
 125
 126                 return root
 127         end
 128
 129         fun short_work(ndoc: ADoc): HTMLTag
 130         do
 131                         var text = ndoc.n_comment.first.text.substring_from(1)
 132                         var n = new HTMLTag("span")
 133                         n.add_class("synopsys")
 134                         n.add_class("nitdoc")
 135                         process_line(n, text)
 136                         return n
 137         end
 138
 139         fun process_line(n: HTMLTag, text: String)
 140         do
 141                 # Loosly detect code parts
 142                 var parts = text.split("`")
 143
 144                 # Process each code parts, thus alternate between text and code
 145                 var is_text = true
 146                 for part in parts do
 147                         if is_text then
 148                                 # Text part
 149                                 n.append part
 150                         else
 151                                 # Code part
 152                                 var n2 = new HTMLTag("code")
 153                                 n.add(n2)
 154                                 process_code(n2, part)
 155                         end
 156                         is_text = not is_text
 157                 end
 158         end
 159
 160         fun close_codeblock(root: HTMLTag)
 161         do
 162                 # Is there a codeblock to manage?
 163                 if not curblock.is_empty then
 164                         var n = new HTMLTag("pre")
 165                         root.add(n)
 166                         var btext = curblock.to_s
 167                         process_code(n, btext)
 168                         curblock.clear
 169                 end
 170         end
 171
 172         fun process_code(n: HTMLTag, text: String)
 173         do
 174                 n.append text
 175         end
 176 end
 177
 178 redef class ADoc
 179         # Build a `<div>` element that contains the full documentation in HTML
 180         fun full_markdown: HTMLTag
 181         do
 182                 var tc = new ToolContext
 183                 var d2m = new Doc2Mdwn(tc)
 184                 return d2m.work(self)
 185         end
 186
 187         # Build a `<span>` element that contains the synopsys in HTML
 188         fun short_markdown: HTMLTag
 189         do
 190                 var tc = new ToolContext
 191                 var d2m = new Doc2Mdwn(tc)
 192                 return d2m.short_work(self)
 193         end
 194 end