1 files changed, 147 insertions, 0 deletions
diff --git a/tools/link_gen.lua b/tools/link_gen.lua
new file mode 100644
index 0000000..d23b923
--- /dev/null
+++ b/tools/link_gen.lua
@@ -0,0 +1,147 @@
+local pipe = pandoc.pipe
+local stringify = (require 'pandoc.utils').stringify
+
+local meta = PANDOC_DOCUMENT.meta
+local preview = ""
+local internal_links = {}
+local max_string_length = 100
+
+local function append_str(buf, s)
+    if (#buf + #s) < max_string_length then
+        buf = buf .. s
+    end
+
+    return buf
+end
+
+local function file_exists(name)
+  local f = io.open(name, 'r')
+  if f ~= nil then
+    io.close(f)
+    return true
+  else
+    return false
+  end
+end
+
+local function read_link_file(name)
+    local f = io.open(name, 'r')
+    if f ~= nil then
+        local output = {}
+        for line in f:lines() do
+            table.insert(output, line)
+        end
+        f:close()
+        return output
+    else
+        return {}
+    end
+end
+
+local function write_link_file(name, links)
+    local f = io.open(name, 'w')
+    for i,v in ipairs(links) do
+        f:write(string.format("%s\n", v))
+    end
+    f:close()
+end
+
+local function item_in_table(table, item)
+    local inside = false
+    for i,v in ipairs(table) do
+        if v == item then
+            inside = true
+            break
+        end
+    end
+
+    return inside
+end
+
+local function get_filename(file)
+    return file:match("^.+/(.+)$")
+end
+
+local function get_input_file()
+    local file = PANDOC_STATE.input_files[1]
+    file = get_filename(file)
+    file = string.gsub(file, ".md", "")
+    return file
+end
+
+function Doc(body, metadata, variables)
+    local input_file = get_input_file()
+
+    -- Write out link file for table
+    for i,v in ipairs(internal_links) do
+        local markdown_file = "./notes/" .. v .. ".md"
+        local link_file = "./build/" .. v .. ".links"
+
+        -- check if markdown version of the file exists
+        if file_exists(markdown_file) then
+            links = read_link_file(link_file) 
+            if not item_in_table(links, input_file) then
+                table.insert(links, input_file)
+            end
+
+            write_link_file(link_file, links)
+        else
+            io.stderr:write(string.format("Linking to non-existant file '%s'\n", v))
+        end
+    end
+
+    local values = {}
+    local output = ""
+    for k,v in pairs(meta) do
+        values[k] = stringify(v)
+    end
+
+    values["preview"] = preview
+    for k,v in pairs(values) do
+        output = output .. string.format("%s,%s\n", k, v)
+    end
+
+    return output
+end
+
+function Str(s)
+    preview = append_str(preview, s)
+    return ""
+end
+
+function Space()
+    preview = append_str(preview, " ")
+    return ""
+end
+
+function SoftBreak()
+    return Space()
+end
+
+function LineBreak()
+    return Space()
+end
+
+function Link(s, tgt, tit, attr)
+    if not string.find(tgt, "://") then
+        -- Check if link is already found elsewhere in document
+        local value_found = false
+        for index, value in ipairs(internal_links) do
+            if value == tgt then value_found = true end
+        end
+
+        if not value_found then
+            table.insert(internal_links, tgt)
+        end
+    end
+    return ""
+end
+
+
+-- Ignore functions we haven't implemented as we don't need them
+local meta = {}
+meta.__index =
+  function(_, key)
+    return function() return '' end
+  end
+setmetatable(_G, meta)