Initial commit

.obsidian/plugins/obsidian-enhancing-export/lua/markdown.lua

@@ -0,0 +1,235 @@
+package.path=debug.getinfo(1).source:gsub('@',''):sub(0):match('(.*[/\\])'):sub(0) .. '?.lua' .. ';' .. package.path
+
+require("polyfill")
+local url = require('url')
+
+local pandoc=pandoc
+local PANDOC_STATE=PANDOC_STATE
+
+PANDOC_VERSION:must_be_at_least '2.17'
+
+local PATH = pandoc.path
+local doc_dir = nil
+local media_dir = nil
+
+if Mode == nil then
+  Mode = 'default'
+end
+
+-- print("Mode: "..Mode)
+
+if PANDOC_STATE.output_file then
+  local output_file = PANDOC_STATE.output_file
+  doc_dir = PATH.directory(output_file)
+  if PANDOC_WRITER_OPTIONS.variables["media_dir"] then
+    media_dir = PANDOC_WRITER_OPTIONS.variables["media_dir"]
+  else
+    media_dir = PATH.split_extension(output_file)
+    if Mode ~= 'hugo' then
+      media_dir = media_dir .. '-media'
+    end
+  end
+end
+assert(doc_dir, "doc_dir is nil")
+assert(media_dir, "media_dir is nil")
+
+
+local function get_absolute_path(file_path)
+  if PATH.is_absolute(file_path) then
+    return file_path
+  end
+  for _, dir in pairs(PANDOC_STATE.resource_path) do
+    local full_path = PATH.join({dir, file_path})
+    if os.exists(full_path) then
+      return full_path
+    end
+  end
+  for _, file in pairs(PANDOC_STATE.input_files) do
+    if not PATH.is_absolute(file) then
+      file = PATH.join({pandoc.system.get_working_directory(), file_path})
+    end
+    local dir = PATH.directory(file)
+    local full_path = PATH.join({dir, file_path})
+    if os.exists(full_path) then
+      return full_path
+    end
+  end
+  return nil
+end
+
+local function get_output_file(file_path)
+  if media_dir then
+    local new_file_name = pandoc.utils.sha1(file_path)
+    local _, new_file_ext = PATH.split_extension(file_path)
+    file_path = new_file_name .. new_file_ext
+    local full_path = PATH.join({media_dir, file_path})
+    return full_path
+  else
+    return nil
+  end
+end
+
+local function extract_media(file_path)
+  os.mkdir(media_dir)
+  file_path = url.decode(file_path)
+  local abs_path = get_absolute_path(file_path)
+  local file = get_output_file(file_path)
+  if abs_path and file then
+    if not os.exists(file) then
+      os.copy(abs_path, file)
+    end
+    local rel_path = PATH.make_relative(file, doc_dir, false)
+    local parts = PATH.split(rel_path)
+    for i,v in ipairs(parts) do
+      parts[i] = url.encode(v)
+    end
+    local encoded_rel_path = table.concat(parts, "/")
+    if Mode == 'hugo' then
+      encoded_rel_path = '../' .. encoded_rel_path
+    end
+    return encoded_rel_path
+  end
+end
+
+local function raw(s)
+  return pandoc.RawInline('markdown', s)
+end
+
+function Image(el)
+  local src = extract_media(el.src)
+  if src then
+    el.src = src
+  end
+  return el
+end
+
+function Space()
+  return raw(' ')
+end
+
+function SoftBreak()
+  return raw('\n')
+end
+
+function RawInline(el)
+  if el.format == "html" then
+    el.format = 'markdown'
+    el.text = string.gsub(el.text, '<img[^>]+>', function(img)
+      return string.gsub(img, 'src="([^"]+)"', function(url)
+        if string.find(url, '^[Hh][Tt][Tt][Pp][Ss]?://') == nil  then
+          local extract_media_url = extract_media(url)
+          if extract_media_url then
+            return 'src="' .. extract_media_url .. '"'
+          end
+          return '123'
+        end
+        return 'src="' .. url .. '"'
+      end)
+    end)
+  end
+  return el
+end
+
+function RawBlock(el)
+  if el.format == "html" then
+    el.format = 'markdown'
+  end
+  return el
+end
+
+function Math(el)
+  if Mode == 'hugo' then
+    if el.mathtype == 'DisplayMath' then
+      return raw('{{< mathjax >}}\n$$'  .. el.text .. '$$\n{{</mathjax >}}')
+    else
+      el.text = string.gsub(el.text, '\\[\\{\\}]', function (v)
+        return '\\' .. v
+      end)
+      el.text = string.gsub(el.text, '_', function (v)
+        return '\\' .. v
+      end)
+    end
+  end
+  return el
+end
+
+local function headerLink(input)
+  -- github style section link
+  return "#"..input:gsub(' ', '-')
+end
+
+
+local function insertLink(content, linkDescription)
+  local descriptionText = table.concat(linkDescription, "")
+
+  if string.find(descriptionText, '|') then
+    local target, desc = descriptionText:match("(.*)|(.*)")
+    table.insert(content, pandoc.Link(desc, headerLink(target)))
+  else
+    table.insert(content, pandoc.Link(descriptionText, headerLink(descriptionText)))
+  end
+end
+
+function Para(el)
+  local content = el.content
+  content = ProcessMath(content)
+  content = ProcessInternalLinks(content)
+  el.content = content
+  return el
+end
+
+function ProcessMath(elements)
+  local content = {}
+  local in_display_math = false
+  for _, item in pairs(elements) do
+    if item.t == 'Str'and item.text == "$$" then
+      in_display_math = not in_display_math
+    else
+      if in_display_math then
+        if item.t == 'RawInline' and item.format == 'tex' then
+          local n = pandoc.Math('DisplayMath', '\n' .. item.text .. '\n')
+          table.insert(content, Math(n))
+        else
+          table.insert(content, item)
+        end
+      else
+        table.insert(content, item)
+      end
+    end
+  end
+  return content
+end
+
+function ProcessInternalLinks(elements)
+  local content = {}
+  local in_section_link = false
+  local linkDescription = {}
+
+  for _, item in pairs(elements) do
+    if item.t == 'Str' and string.starts_with(item.text, '[[#') then
+      in_section_link = true
+      table.insert(linkDescription, string.sub(item.text, 4))
+    elseif in_section_link then
+      if string.ends_with(item.text, ']]') then
+        table.insert(linkDescription, string.sub(item.text, 1, -3))
+        insertLink(content, linkDescription)
+        in_section_link = false
+        linkDescription = {}
+      else
+        table.insert(linkDescription, item.text)
+      end
+    else
+      table.insert(content, item)
+    end
+  end
+  return content
+end
+
+function Plain(el)
+  el.content = ProcessInternalLinks(el.content)
+  return el
+end
+
+function Pandoc(el)
+  return el
+end