Refactor/omnicompletion (#620)

Co-authored-by: Sebastian Flügge <seflue@users.noreply.github.com>

Author: seflue

ftplugin/org.vim

@@ -12,7 +12,7 @@ function! OrgmodeFoldText()
 endfunction
 
 function! OrgmodeOmni(findstart, base)
-  return luaeval('require("orgmode.org.autocompletion.omni")(_A[1], _A[2])', [a:findstart, a:base])
+  return luaeval('require("orgmode.org.autocompletion.omni").omnifunc(_A[1], _A[2])', [a:findstart, a:base])
 endfunction
 
 function! OrgmodeFormatExpr()

lua/orgmode/org/autocompletion/cmp.lua

@@ -3,7 +3,7 @@ if not has_cmp then
   return
 end
 
-local OrgmodeOmniCompletion = require('orgmode.org.autocompletion.omni')
+local Omni = require('orgmode.org.autocompletion.omni')
 
 local Source = {}
 
@@ -25,9 +25,9 @@ function Source:get_trigger_characters(_)
 end
 
 function Source:complete(params, callback)
-  local offset = OrgmodeOmniCompletion(1, '') + 1
+  local offset = Omni.find_start() + 1
   local input = string.sub(params.context.cursor_before_line, offset)
-  local results = OrgmodeOmniCompletion(0, input)
+  local results = Omni.get_completions(input)
   local items = {}
   for _, item in ipairs(results) do
     table.insert(items, {

lua/orgmode/org/autocompletion/compe.lua

@@ -3,7 +3,7 @@ if not has_compe then
   return
 end
 
-local OrgmodeOmniCompletion = require('orgmode.org.autocompletion.omni')
+local Omni = require('orgmode.org.autocompletion.omni')
 
 local CompeSource = {}
 
@@ -22,7 +22,7 @@ function CompeSource.get_metadata()
 end
 
 function CompeSource.determine(_, context)
-  local offset = OrgmodeOmniCompletion(1, '') + 1
+  local offset = Omni.find_start() + 1
   if offset > 0 then
     return {
       keyword_pattern_offset = offset,
@@ -32,7 +32,7 @@ function CompeSource.determine(_, context)
 end
 
 function CompeSource.complete(_, context)
-  local items = OrgmodeOmniCompletion(0, context.input)
+  local items = Omni.get_completions(context.input)
   context.callback({
     items = items,
     incomplete = true,

lua/orgmode/org/autocompletion/omni.lua

@@ -2,7 +2,6 @@ local Files = require('orgmode.parser.files')
 local config = require('orgmode.config')
 local Hyperlinks = require('orgmode.org.hyperlinks')
 local Url = require('orgmode.objects.url')
-local Link = require('orgmode.objects.link')
 
 local data = {
   directives = { '#+title', '#+author', '#+email', '#+name', '#+filetags', '#+archive', '#+options', '#+category' },
@@ -33,8 +32,8 @@ local properties = {
 }
 
 local links = {
-  line_rgx = vim.regex([[\(\(^\|\s\+\)\[\[\)\@<=\(\*\|\#\|file:\)\?\(\(\w\|\/\|\.\|\\\|-\|_\|\d\)\+\)\?]]),
-  rgx = vim.regex([[\(\*\|\#\|file:\)\?\(\(\w\|\/\|\.\|\\\|-\|_\|\d\)\+\)\?$]]),
+  line_rgx = vim.regex([[\(\(^\|\s\+\)\[\[\)\@<=\(\*\|#\|file:\)\?\(\(\w\|\/\|\.\|\\\|-\)\+\)\?]]),
+  rgx = vim.regex([[\(\*\|#\|file:\)\?\(\(\w\|\/\|\.\|\\\|-\)\+\)\?$]]),
   fetcher = function(url)
     local hyperlinks, mapper = Hyperlinks.find_matching_links(url)
     return mapper(hyperlinks)
@@ -91,54 +90,84 @@ local headline_contexts = {
   todo_keywords,
 }
 
+local Omni = {}
+
+---@return string: the line before the current cursor position
+function Omni.get_line_content_before_cursor()
+  return vim.api.nvim_get_current_line():sub(1, vim.api.nvim_call_function('col', { '.' }) - 1)
+end
+
+function Omni.is_headline()
+  return Omni.get_line_content_before_cursor():match('^%*+%s+')
+end
+
+---@return Table
+function Omni.get_all_contexts()
+  return Omni.is_headline() and headline_contexts or contexts
+end
+
 ---Determines an URL for link handling. Handles a couple of corner-cases
 ---@param base string The string to complete
 ---@return string
-local function get_url_str(line, base)
+function Omni.get_url_str(line, base)
   local line_base = line:match('%[%[(.-)$') or line
   line_base = line_base:gsub(base .. '$', '')
   return (line_base or '') .. (base or '')
 end
 
---- This function is registered to omnicompletion in ftplugin/org.vim.
----
---- If the user want to use it in his completion plugin (like cmp) he has to do
---- that in the configuration of that plugin.
----@return table
-local function omni(findstart, base)
-  local line = vim.api.nvim_get_current_line():sub(1, vim.api.nvim_call_function('col', { '.' }) - 1)
-  local is_headline = line:match('^%*+%s+')
-  local ctx = is_headline and headline_contexts or contexts
-  if findstart == 1 then
-    for _, context in ipairs(ctx) do
-      local word = context.rgx:match_str(line)
-      if word and (not context.extra_cond or context.extra_cond(line, base)) then
-        return word
-      end
+--- Is true and only true, if all given regex in the context match appropriatly
+--- line_rgx and extra_cond are optional, but if the context defines them, they must match.
+--- The basic rgx must always match the base, because it is used to determine the start position for
+--- the completion.
+---@param context table: the context candidate
+---@param line string: characters left to the cursor
+---@param base string: characters after the trigger (filter)
+function Omni.all_ctx_conditions_apply(context, line, base)
+  return (not context.line_rgx or context.line_rgx:match_str(line))
+    and context.rgx:match_str(base)
+    and (not context.extra_cond or context.extra_cond(line, base))
+end
+
+---@param base? string
+---@return number
+function Omni.find_start(base)
+  local line = Omni.get_line_content_before_cursor()
+  for _, context in ipairs(Omni.get_all_contexts()) do
+    local word = context.rgx:match_str(line)
+    if word and (not context.extra_cond or context.extra_cond(line, base)) then
+      return word
     end
-    return -1
   end
+  return -1
+end
 
-  local url = Url.new(get_url_str(line, base))
-  local results = {}
+---@param base string
+---@return table
+function Omni.get_completions(base)
+  -- Workaround for the corner case of matching custom_ids to file paths without file: prefix
+  -- Bug is probably in the regex, but hard to fix, because the regex is so hard to read
+  base = base:match('^:#') and base:gsub('^:', '') or base
 
-  for _, context in ipairs(ctx) do
-    if
-      (not context.line_rgx or context.line_rgx:match_str(line))
-      and context.rgx:match_str(base)
-      and (not context.extra_cond or context.extra_cond(line, base))
-    then
+  local line = Omni.get_line_content_before_cursor()
+  local url = Url.new(Omni.get_url_str(line, base))
+  local results = {}
+  for _, context in ipairs(Omni.get_all_contexts()) do
+    if Omni.all_ctx_conditions_apply(context, line, base) then
       local items = {}
+
+      -- fetch or just take context specific completion candidates
       if context.fetcher then
         items = context.fetcher(url)
       else
         items = { unpack(context.list) }
       end
 
+      -- incrementally limit candidates to what the user has already been typed
       items = vim.tbl_filter(function(i)
         return i:find('^' .. vim.pesc(base))
       end, items)
 
+      -- craft the actual completion entries and append them to the overall results
       for _, item in ipairs(items) do
         table.insert(results, { word = item, menu = '[Org]' })
       end
@@ -148,4 +177,8 @@ local function omni(findstart, base)
   return results
 end
 
-return omni
+function Omni.omnifunc(findstart, base)
+  return findstart == 1 and Omni.find_start(base) or Omni.get_completions(base)
+end
+
+return Omni