Soft Line Wrapping (#636)

Added in soft line wrapping.

4 files changed, 581 insertions, 52 deletions

diff --git a/data/core/commands/doc.lua b/data/core/commands/doc.lua
index ed35913a..597e3de4 100644
--- a/data/core/commands/doc.lua
+++ b/data/core/commands/doc.lua
@@ -549,29 +549,29 @@ local commands = {
 
 
 local translations = {
-  ["previous-char"] = translate.previous_char,
-  ["next-char"] = translate.next_char,
-  ["previous-word-start"] = translate.previous_word_start,
-  ["next-word-end"] = translate.next_word_end,
-  ["previous-block-start"] = translate.previous_block_start,
-  ["next-block-end"] = translate.next_block_end,
-  ["start-of-doc"] = translate.start_of_doc,
-  ["end-of-doc"] = translate.end_of_doc,
-  ["start-of-line"] = translate.start_of_line,
-  ["end-of-line"] = translate.end_of_line,
-  ["start-of-word"] = translate.start_of_word,
-  ["start-of-indentation"] = translate.start_of_indentation,
-  ["end-of-word"] = translate.end_of_word,
-  ["previous-line"] = DocView.translate.previous_line,
-  ["next-line"] = DocView.translate.next_line,
-  ["previous-page"] = DocView.translate.previous_page,
-  ["next-page"] = DocView.translate.next_page,
+  ["previous-char"] = translate,
+  ["next-char"] = translate,
+  ["previous-word-start"] = translate,
+  ["next-word-end"] = translate,
+  ["previous-block-start"] = translate,
+  ["next-block-end"] = translate,
+  ["start-of-doc"] = translate,
+  ["end-of-doc"] = translate,
+  ["start-of-line"] = translate,
+  ["end-of-line"] = translate,
+  ["start-of-word"] = translate,
+  ["start-of-indentation"] = translate,
+  ["end-of-word"] = translate,
+  ["previous-line"] = DocView.translate,
+  ["next-line"] = DocView.translate,
+  ["previous-page"] = DocView.translate,
+  ["next-page"] = DocView.translate,
 }
 
-for name, fn in pairs(translations) do
-  commands["doc:move-to-" .. name] = function() doc():move_to(fn, dv()) end
-  commands["doc:select-to-" .. name] = function() doc():select_to(fn, dv()) end
-  commands["doc:delete-to-" .. name] = function() doc():delete_to(fn, dv()) end
+for name, obj in pairs(translations) do
+  commands["doc:move-to-" .. name] = function() doc():move_to(obj[name:gsub("-", "_")], dv()) end
+  commands["doc:select-to-" .. name] = function() doc():select_to(obj[name:gsub("-", "_")], dv()) end
+  commands["doc:delete-to-" .. name] = function() doc():delete_to(obj[name:gsub("-", "_")], dv()) end
 end
 
 commands["doc:move-to-previous-char"] = function()
diff --git a/data/core/commandview.lua b/data/core/commandview.lua
index b91f1394..4396313f 100644
--- a/data/core/commandview.lua
+++ b/data/core/commandview.lua
@@ -56,8 +56,8 @@ function CommandView:get_name()
 end
 
 
-function CommandView:get_line_screen_position()
-  local x = CommandView.super.get_line_screen_position(self, 1)
+function CommandView:get_line_screen_position(line, col)
+  local x = CommandView.super.get_line_screen_position(self, 1, col)
   local _, y = self:get_content_offset()
   local lh = self:get_line_height()
   return x, y + (self.size.y - lh) / 2
@@ -243,6 +243,7 @@ function CommandView:draw_line_gutter(idx, x, y)
   x = x + style.padding.x
   renderer.draw_text(self:get_font(), self.label, x, y + yoffset, color)
   core.pop_clip_rect()
+  return self:get_line_height()
 end
 
 
diff --git a/data/core/docview.lua b/data/core/docview.lua
index 397b455e..ac3c19d9 100644
--- a/data/core/docview.lua
+++ b/data/core/docview.lua
@@ -121,14 +121,18 @@ function DocView:get_gutter_width()
 end
 
 
-function DocView:get_line_screen_position(idx)
+function DocView:get_line_screen_position(line, col)
   local x, y = self:get_content_offset()
   local lh = self:get_line_height()
   local gw = self:get_gutter_width()
-  return x + gw, y + (idx-1) * lh + style.padding.y
+  y = y + (line-1) * lh + style.padding.y
+  if col then
+    return x + gw + self:get_col_x_offset(line, col), y
+  else
+    return x + gw, y
+  end
 end
 
-
 function DocView:get_line_text_y_offset()
   local lh = self:get_line_height()
   local th = self:get_font():get_height()
@@ -198,8 +202,9 @@ end
 function DocView:scroll_to_line(line, ignore_if_visible, instant)
   local min, max = self:get_visible_line_range()
   if not (ignore_if_visible and line > min and line < max) then
-    local lh = self:get_line_height()
-    self.scroll.to.y = math.max(0, lh * (line - 1) - self.size.y / 2)
+    local x, y = self:get_line_screen_position(line)
+    local ox, oy = self:get_content_offset()
+    self.scroll.to.y = math.max(0, y - oy - self.size.y / 2)
     if instant then
       self.scroll.y = self.scroll.to.y
     end
@@ -208,10 +213,10 @@ end
 
 
 function DocView:scroll_to_make_visible(line, col)
-  local min = self:get_line_height() * (line - 1)
-  local max = self:get_line_height() * (line + 2) - self.size.y
-  self.scroll.to.y = math.min(self.scroll.to.y, min)
-  self.scroll.to.y = math.max(self.scroll.to.y, max)
+  local ox, oy = self:get_content_offset()
+  local _, ly = self:get_line_screen_position(line, col)
+  local lh = self:get_line_height()
+  self.scroll.to.y = common.clamp(self.scroll.to.y, ly - oy - self.size.y + lh * 2, ly - oy - lh)
   local gw = self:get_gutter_width()
   local xoffset = self:get_col_x_offset(line, col)
   local xmargin = 3 * self:get_font():get_width(' ')
@@ -314,14 +319,15 @@ function DocView:draw_line_highlight(x, y)
 end
 
 
-function DocView:draw_line_text(idx, x, y)
+function DocView:draw_line_text(line, x, y)
   local default_font = self:get_font()
   local tx, ty = x, y + self:get_line_text_y_offset()
-  for _, type, text in self.doc.highlighter:each_token(idx) do
+  for _, type, text in self.doc.highlighter:each_token(line) do
     local color = style.syntax[type]
     local font = style.syntax_fonts[type] or default_font
     tx = renderer.draw_text(font, text, tx, ty, color)
   end
+  return self:get_line_height()
 end
 
 function DocView:draw_caret(x, y)
@@ -329,7 +335,7 @@ function DocView:draw_caret(x, y)
     renderer.draw_rect(x, y, style.caret_width, lh, style.caret)
 end
 
-function DocView:draw_line_body(idx, x, y)
+function DocView:draw_line_body(line, x, y)
   -- draw highlight if any selection ends on this line
   local draw_highlight = false
   local hcl = config.highlight_current_line
@@ -352,14 +358,14 @@ function DocView:draw_line_body(idx, x, y)
   end
 
   -- draw selection if it overlaps this line
+  local lh = self:get_line_height()
   for lidx, line1, col1, line2, col2 in self.doc:get_selections(true) do
-    if idx >= line1 and idx <= line2 then
-      local text = self.doc.lines[idx]
-      if line1 ~= idx then col1 = 1 end
-      if line2 ~= idx then col2 = #text + 1 end
-      local x1 = x + self:get_col_x_offset(idx, col1)
-      local x2 = x + self:get_col_x_offset(idx, col2)
-      local lh = self:get_line_height()
+    if line >= line1 and line <= line2 then
+      local text = self.doc.lines[line]
+      if line1 ~= line then col1 = 1 end
+      if line2 ~= line then col2 = #text + 1 end
+      local x1 = x + self:get_col_x_offset(line, col1)
+      local x2 = x + self:get_col_x_offset(line, col2)
       if x1 ~= x2 then
         renderer.draw_rect(x1, y, x2 - x1, lh, style.selection)
       end
@@ -367,20 +373,22 @@ function DocView:draw_line_body(idx, x, y)
   end
 
   -- draw line's text
-  self:draw_line_text(idx, x, y)
+  return self:draw_line_text(line, x, y)
 end
 
 
-function DocView:draw_line_gutter(idx, x, y, width)
+function DocView:draw_line_gutter(line, x, y, width)
   local color = style.line_number
   for _, line1, _, line2 in self.doc:get_selections(true) do
-    if idx >= line1 and idx <= line2 then
+    if line >= line1 and line <= line2 then
       color = style.line_number2
       break
     end
   end
   x = x + style.padding.x
-  common.draw_text(self:get_font(), color, idx, "right", x, y, width,  self:get_line_height())
+  local lh = self:get_line_height()
+  common.draw_text(self:get_font(), color, line, "right", x, y + yoffset, width, lh)
+  return lh
 end
 
 
@@ -394,8 +402,7 @@ function DocView:draw_overlay()
       and system.window_has_focus() then
         if config.disable_blink
         or (core.blink_timer - core.blink_start) % T < T / 2 then
-          local x, y = self:get_line_screen_position(line)
-          self:draw_caret(x + self:get_col_x_offset(line, col), y)
+          self:draw_caret(self:get_line_screen_position(line, col))
         end
       end
     end
@@ -413,8 +420,7 @@ function DocView:draw()
   local x, y = self:get_line_screen_position(minline)
   local gw, gpad = self:get_gutter_width()
   for i = minline, maxline do
-    self:draw_line_gutter(i, self.position.x, y, gpad and gw - gpad or gw)
-    y = y + lh
+    y = y + (self:draw_line_gutter(i, self.position.x, y, gpad and gw - gpad or gw) or lh)
   end
 
   local pos = self.position
@@ -423,8 +429,7 @@ function DocView:draw()
   -- right side it is redundant with the Node's clip.
   core.push_clip_rect(pos.x + gw, pos.y, self.size.x - gw, self.size.y)
   for i = minline, maxline do
-    self:draw_line_body(i, x, y)
-    y = y + lh
+    y = y + (self:draw_line_body(i, x, y) or lh)
   end
   self:draw_overlay()
   core.pop_clip_rect()
diff --git a/data/plugins/linewrapping.lua b/data/plugins/linewrapping.lua
new file mode 100644
index 00000000..aecc2bab
--- /dev/null
+++ b/data/plugins/linewrapping.lua
@@ -0,0 +1,523 @@
+-- mod-version:2 -- lite-xl 2.0
+local core = require "core"
+local common = require "core.common"
+local DocView = require "core.docview"
+local Doc = require "core.doc"
+local style = require "core.style"
+local config = require "core.config"
+local command = require "core.command"
+local keymap = require "core.keymap"
+local translate = require "core.doc.translate"
+
+config.plugins.linewrapping = {
+	-- The type of wrapping to perform. Can be "letter" or "word".
+  mode = "letter",
+	-- If nil, uses the DocView's size, otherwise, uses this exact width.
+  width_override = nil,
+	-- Whether or not to draw a guide
+  guide = true,
+  -- Whether or not we should indent ourselves like the first line of a wrapped block.
+  indent = true,
+  -- Whether or not to enable wrapping by default when opening files.
+  enable_by_default = true
+}
+
+local LineWrapping = {}
+
+-- Computes the breaks for a given line, width and mode. Returns a list of columns
+-- at which the line should be broken.
+function LineWrapping.compute_line_breaks(doc, default_font, line, width, mode)
+  local xoffset, last_i, i, last_space, last_width, begin_width = 0, 1, 1, 1, 0, 0
+  local splits = { 1 }
+  for idx, type, text in doc.highlighter:each_token(line) do
+    local font = style.syntax_fonts[type] or default_font
+    if idx == 1 and config.plugins.linewrapping.indent then
+      local _, indent_end = text:find("^%s+")
+      if indent_end then begin_width = font:get_width(text:sub(1, indent_end)) end
+    end
+    local w = font:get_width(text)
+    if xoffset + w > width then
+      for char in common.utf8_chars(text) do
+        w = font:get_width(char)
+        xoffset = xoffset + w
+        if xoffset > width then
+          if mode == "word" then
+            table.insert(splits, last_space + 1)
+            xoffset = xoffset - last_width + w + begin_width
+          else
+            table.insert(splits, i)
+            xoffset = w + begin_width
+          end
+        elseif char == ' ' then
+          last_space = i
+          last_width = xoffset
+        end
+        i = i + #char
+      end
+    else
+      xoffset = xoffset + w
+      i = i + #text
+    end
+  end
+  return splits, begin_width
+end
+
+-- breaks are held in a single table that contains n*2 elements, where n is the amount of line breaks.
+-- each element represents line and column of the break. line_offset will check from the specified line
+-- if the first line has not changed breaks, it will stop there.
+function LineWrapping.reconstruct_breaks(docview, default_font, width, line_offset)
+  if width ~= math.huge then
+    local doc = docview.doc
+    -- two elements per wrapped line; first maps to original line number, second to column number.
+    docview.wrapped_lines = { }
+    -- one element per actual line; maps to the first index of in wrapped_lines for this line
+    docview.wrapped_line_to_idx = { }
+    -- one element per actual line; gives the indent width for the acutal line
+    docview.wrapped_line_offsets = { }
+    docview.wrapped_settings = { ["width"] = width, ["font"] = default_font }
+    for i = line_offset or 1, #doc.lines do
+      local breaks, offset = LineWrapping.compute_line_breaks(doc, default_font, i, width, config.plugins.linewrapping.mode)
+      table.insert(docview.wrapped_line_offsets, offset)
+      for k, col in ipairs(breaks) do
+        table.insert(docview.wrapped_lines, i)
+        table.insert(docview.wrapped_lines, col)
+      end
+    end
+    -- list of indices for wrapped_lines, that are based on original line number
+    -- holds the index to the first in the wrapped_lines list.
+    local last_wrap = nil
+    for i = 1, #docview.wrapped_lines, 2 do
+      if not last_wrap or last_wrap ~= docview.wrapped_lines[i] then
+        table.insert(docview.wrapped_line_to_idx, (i + 1) / 2)
+        last_wrap = docview.wrapped_lines[i]
+      end
+    end
+  else
+    docview.wrapped_lines = nil
+    docview.wrapped_line_to_idx = nil
+    docview.wrapped_line_offsets = nil
+    docview.wrapped_settings = nil
+  end
+end
+  
+-- When we have an insertion or deletion, we have four sections of text.
+-- 1. The unaffected section, located prior to the cursor. This is completely ignored.
+-- 2. The beginning of the affected line prior to the insertion or deletion. Begins on column 1 of the selection.
+-- 3. The removed/pasted lines. 
+-- 4. Every line after the modification, begins one line after the selection in the initial document.
+function LineWrapping.update_breaks(docview, old_line1, old_line2, net_lines)
+  -- Step 1: Determine the index for the line for #2.
+  local old_idx1 = docview.wrapped_line_to_idx[old_line1] or 1
+  -- Step 2: Determine the index of the line for #4.
+  local old_idx2 = (docview.wrapped_line_to_idx[old_line2 + 1] or ((#docview.wrapped_lines / 2) + 1)) - 1
+  -- Step 3: Remove all old breaks for the old lines from the table, and all old widths from wrapped_line_offsets.
+  local offset = (old_idx1  - 1) * 2 + 1
+  for i = old_idx1, old_idx2 do
+    table.remove(docview.wrapped_lines, offset)
+    table.remove(docview.wrapped_lines, offset)
+  end
+  for i = old_line1, old_line2 do
+    table.remove(docview.wrapped_line_offsets, old_line1)
+  end
+  -- Step 4: Shift the line number of wrapped_lines past #4 by the amount of inserted/deleted lines.
+  if net_lines ~= 0 then 
+    for i = offset, #docview.wrapped_lines, 2 do
+      docview.wrapped_lines[i] = docview.wrapped_lines[i] + net_lines
+    end
+  end  
+  -- Step 5: Compute the breaks and offsets for the lines for #2 and #3. Insert them into the table.
+  local new_line1 = old_line1
+  local new_line2 = old_line2 + net_lines
+  for line = new_line1, new_line2 do
+    local breaks, begin_width = LineWrapping.compute_line_breaks(docview.doc, docview.wrapped_settings.font, line, docview.wrapped_settings.width, config.plugins.linewrapping.mode)  
+    table.insert(docview.wrapped_line_offsets, line, begin_width)
+    for i,b in ipairs(breaks) do
+      table.insert(docview.wrapped_lines, offset, b)
+      table.insert(docview.wrapped_lines, offset, line)
+      offset = offset + 2
+    end
+  end
+  -- Step 6: Recompute the wrapped_line_to_idx cache from #2.
+  local line = old_line1
+  offset = (old_idx1  - 1) * 2 + 1
+  while offset < #docview.wrapped_lines do
+    if docview.wrapped_lines[offset + 1] == 1 then
+      docview.wrapped_line_to_idx[line] = ((offset - 1) / 2) + 1
+      line = line + 1
+    end
+    offset = offset + 2
+  end
+  while line <= #docview.wrapped_line_to_idx do
+    table.remove(docview.wrapped_line_to_idx)
+  end
+end
+
+-- Draws a guide if applicable to show where wrapping is occurring.
+function LineWrapping.draw_guide(docview)
+  if config.plugins.linewrapping.guide and docview.wrapped_settings.width ~= math.huge then
+    local x, y = docview:get_content_offset()
+    local gw = docview:get_gutter_width()
+    renderer.draw_rect(x + gw + docview.wrapped_settings.width, y, 1, core.root_view.size.y, style.selection)
+  end
+end
+
+function LineWrapping.update_docview_breaks(docview)
+  local x,y,w,h = docview:get_scrollbar_rect()
+  local width = config.plugins.linewrapping.width_override or (docview.size.x - docview:get_gutter_width() - w)
+  if (not docview.wrapped_settings or docview.wrapped_settings.width == nil or width ~= docview.wrapped_settings.width) then
+    docview.scroll.to.x = 0
+    LineWrapping.reconstruct_breaks(docview, docview:get_font(), width)
+  end
+end
+
+local function get_idx_line_col(docview, idx)
+  local doc = docview.doc
+  if not docview.wrapped_settings then 
+    if idx > #doc.lines then return #doc.lines, #doc.lines[#doc.lines] + 1 end
+    return idx, 1 
+  end
+  if idx < 1 then return 1, 1 end
+  local offset = (idx - 1) * 2 + 1
+  if offset > #docview.wrapped_lines then return #doc.lines, #doc.lines[#doc.lines] + 1 end
+  return docview.wrapped_lines[offset], docview.wrapped_lines[offset + 1]
+end
+
+local function get_idx_line_length(docview, idx)
+  local doc = docview.doc
+  if not docview.wrapped_settings then 
+    if idx > #doc.lines then return #doc.lines[#doc.lines] + 1 end
+    return #doc.lines[idx]
+  end
+  local offset = (idx - 1) * 2 + 1
+  local start = docview.wrapped_lines[offset + 1]
+  if docview.wrapped_lines[offset + 2] and docview.wrapped_lines[offset + 2] == docview.wrapped_lines[offset] then
+    return docview.wrapped_lines[offset + 3] - docview.wrapped_lines[offset + 1]
+  else
+    return #doc.lines[docview.wrapped_lines[offset]] - docview.wrapped_lines[offset + 1] + 1
+  end
+end
+
+local function get_total_wrapped_lines(docview)
+  if not docview.wrapped_settings then return docview.doc and #docview.doc.lines end
+  return #docview.wrapped_lines / 2
+end
+
+-- If line end, gives the end of an index line, rather than the first character of the next line.
+local function get_line_idx_col_count(docview, line, col, line_end, ndoc)
+  local doc = docview.doc
+  if not docview.wrapped_settings then return common.clamp(line, 1, #doc.lines), col, 1, 1 end
+  if line > #doc.lines then return get_line_idx_col_count(docview, #doc.lines, #doc.lines[#doc.lines] + 1) end
+  line = math.max(line, 1)
+  local idx = docview.wrapped_line_to_idx[line] or 1
+  local ncol, scol = 1, 1
+  if col then
+    local i = idx + 1
+    while line == docview.wrapped_lines[(i - 1) * 2 + 1] and col >= docview.wrapped_lines[(i - 1) * 2 + 2] do
+      local nscol = docview.wrapped_lines[(i - 1) * 2 + 2]
+      if line_end and col == nscol then
+        break
+      end
+      scol = nscol
+      i = i + 1
+      idx = idx + 1
+    end
+    ncol = (col - scol) + 1
+  end
+  local count = (docview.wrapped_line_to_idx[line + 1] or (get_total_wrapped_lines(docview) + 1)) - (docview.wrapped_line_to_idx[line] or get_total_wrapped_lines(docview))
+  return idx, ncol, count, scol
+end
+
+local function get_line_col_from_index_and_x(docview, idx, x)
+  local doc = docview.doc
+  local line, col = get_idx_line_col(docview, idx)
+  if idx < 1 then return 1, 1 end
+  local xoffset, last_i, i = (col ~= 1 and docview.wrapped_line_offsets[line] or 0), col, 1
+  if x < xoffset then return line, col end
+  local default_font = docview:get_font()
+  for _, type, text in docview.doc.highlighter:each_token(line) do
+    local font, w = style.syntax_fonts[type] or default_font, 0
+    for char in common.utf8_chars(text) do
+      if i >= col then
+        if xoffset >= x then
+          return line, (xoffset - x > (w / 2) and last_i or i)
+        end
+        w = font:get_width(char)
+        xoffset = xoffset + w
+      end
+      last_i = i
+      i = i + #char
+    end
+  end
+  return line, #doc.lines[line]
+end
+
+
+local open_files = {}
+
+local old_doc_insert = Doc.raw_insert
+function Doc:raw_insert(line, col, text, undo_stack, time)
+  local old_lines = #self.lines
+  old_doc_insert(self, line, col, text, undo_stack, time)
+  if open_files[self] then
+    for i,docview in ipairs(open_files[self]) do
+      if docview.wrapped_settings then
+        local lines = #self.lines - old_lines
+        LineWrapping.update_breaks(docview, line, line, lines)
+      end
+    end
+  end
+end
+
+local old_doc_remove = Doc.raw_remove
+function Doc:raw_remove(line1, col1, line2, col2, undo_stack, time)
+  local old_lines = #self.lines
+  old_doc_remove(self, line1, col1, line2, col2, undo_stack, time)
+  if open_files[self] then
+    for i,docview in ipairs(open_files[self]) do
+      if docview.wrapped_settings then
+        local lines = #self.lines - old_lines
+        LineWrapping.update_breaks(docview, line1, line2, lines)
+      end
+    end
+  end
+end
+
+local old_doc_update = DocView.update
+function DocView:update()
+  old_doc_update(self)
+  if self.wrapped_settings and self.size.x > 0 then
+    LineWrapping.update_docview_breaks(self)
+  end
+end
+
+function DocView:get_scrollable_size()
+  if not config.scroll_past_end then
+    return self:get_line_height() * get_total_wrapped_lines(self) + style.padding.y * 2
+  end
+  return self:get_line_height() * (get_total_wrapped_lines(self) - 1) + self.size.y
+end
+
+local old_new = DocView.new
+function DocView:new(doc)
+  old_new(self, doc)
+  if not open_files[doc] then open_files[doc] = {} end
+  table.insert(open_files[doc], self)
+  if config.plugins.linewrapping.enable_by_default then
+    LineWrapping.update_docview_breaks(self)
+  end
+end
+
+local old_scroll_to_make_visible = DocView.scroll_to_make_visible
+function DocView:scroll_to_make_visible(line, col)
+  old_scroll_to_make_visible(self, line, col)
+  if self.wrapped_settings then self.scroll.to.x = 0 end
+end
+
+local old_get_visible_line_range = DocView.get_visible_line_range
+function DocView:get_visible_line_range()
+  if not self.wrapped_settings then return old_get_visible_line_range(self) end
+  local x, y, x2, y2 = self:get_content_bounds()
+  local lh = self:get_line_height()
+  local minline = get_idx_line_col(self, math.max(1, math.floor(y / lh)))
+  local maxline = get_idx_line_col(self, math.min(get_total_wrapped_lines(self), math.floor(y2 / lh) + 1))
+  return minline, maxline
+end
+
+local old_get_x_offset_col = DocView.get_x_offset_col
+function DocView:get_x_offset_col(line, x)
+  if not self.wrapped_settings then return old_get_x_offset_col(self, line, x) end
+  local idx = get_line_idx_col_count(self, line)
+  return get_line_col_from_index_and_x(self, idx, x)
+end
+
+-- If line end is true, returns the end of the previous line, in a multi-line break.
+local old_get_col_x_offset = DocView.get_col_x_offset
+function DocView:get_col_x_offset(line, col, line_end)
+  if not self.wrapped_settings then return old_get_col_x_offset(self, line, col) end
+  local idx, ncol, count, scol = get_line_idx_col_count(self, line, col, line_end)
+  local xoffset, i = (scol ~= 1 and self.wrapped_line_offsets[line] or 0), 1
+  local default_font = self:get_font()
+  for _, type, text in self.doc.highlighter:each_token(line) do
+    if i + #text >= scol then   
+      if i < scol then 
+        text = text:sub(scol - i + 1)
+        i = scol
+      end
+      local font = style.syntax_fonts[type] or default_font
+      for char in common.utf8_chars(text) do
+        if i >= col then
+          return xoffset
+        end
+        xoffset = xoffset + font:get_width(char)
+        i = i + #char
+      end
+    else
+     i = i + #text
+    end
+  end
+  return xoffset
+end
+
+local old_get_line_screen_position = DocView.get_line_screen_position
+function DocView:get_line_screen_position(line, col)
+  if not self.wrapped_settings then return old_get_line_screen_position(self, line, col) end
+  local idx, ncol, count = get_line_idx_col_count(self, line, col)
+  local x, y = self:get_content_offset()
+  local lh = self:get_line_height()
+  local gw = self:get_gutter_width()
+  return x + gw + (col and self:get_col_x_offset(line, col) or 0), y + (idx-1) * lh + style.padding.y
+end
+
+local old_resolve_screen_position = DocView.resolve_screen_position
+function DocView:resolve_screen_position(x, y)
+  if not self.wrapped_settings then return old_resolve_screen_position(self, x, y) end
+  local ox, oy = self:get_line_screen_position(1)
+  local idx = common.clamp(math.floor((y - oy) / self:get_line_height()) + 1, 1, get_total_wrapped_lines(self))
+  return get_line_col_from_index_and_x(self, idx, x - ox)
+end
+
+local old_draw_line_text = DocView.draw_line_text
+function DocView:draw_line_text(line, x, y)
+  if not self.wrapped_settings then return old_draw_line_text(self, line, x, y) end
+  local default_font = self:get_font()
+  local tx, ty, begin_width = x, y + self:get_line_text_y_offset(), self.wrapped_line_offsets[line]
+  local lh = self:get_line_height()
+  local idx, _, count = get_line_idx_col_count(self, line)
+  local total_offset = 1
+  for _, type, text in self.doc.highlighter:each_token(line) do
+    local color = style.syntax[type]
+    local font = style.syntax_fonts[type] or default_font
+    local token_offset = 1
+    -- Split tokens if we're at the end of the document.
+    while text ~= nil and token_offset <= #text do
+      local next_line, next_line_start_col = get_idx_line_col(self, idx + 1)
+      if next_line ~= line then
+        next_line_start_col = #self.doc.lines[line] 
+      end
+      local max_length = next_line_start_col - total_offset
+      local rendered_text = text:sub(token_offset, token_offset + max_length - 1)
+      tx = renderer.draw_text(font, rendered_text, tx, ty, color)
+      total_offset = total_offset + #rendered_text
+      if total_offset ~= next_line_start_col or max_length == 0 then break end
+      token_offset = token_offset + #rendered_text
+      idx = idx + 1
+      tx, ty = x + begin_width, ty + lh
+    end
+  end
+  return lh * count
+end
+
+local old_draw_line_body = DocView.draw_line_body
+function DocView:draw_line_body(line, x, y)
+  if not self.wrapped_settings then return old_draw_line_body(self, line, x, y) end
+  local lh = self:get_line_height()
+  local idx0 = get_line_idx_col_count(self, line)
+  for lidx, line1, col1, line2, col2 in self.doc:get_selections(true) do
+    if line >= line1 and line <= line2 then
+      if line1 ~= line then col1 = 1 end
+      if line2 ~= line then col2 = #self.doc.lines[line] + 1 end
+      if col1 ~= col2 then
+        local idx1, ncol1 = get_line_idx_col_count(self, line, col1)
+        local idx2, ncol2 = get_line_idx_col_count(self, line, col2)
+        for i = idx1, idx2 do
+          local x1, x2 = x + (idx1 == i and self:get_col_x_offset(line1, col1) or 0)
+          if idx2 == i then
+            x2 = x + self:get_col_x_offset(line, col2)
+          else
+            x2 = x + self:get_col_x_offset(line, get_idx_line_length(self, i, line) + 1, true)
+          end
+          renderer.draw_rect(x1, y + (i - idx0) * lh, x2 - x1, lh, style.selection)
+        end
+      end
+    end
+  end
+  local draw_highlight = nil
+  for lidx, line1, col1, line2, col2 in self.doc:get_selections(true) do
+    -- draw line highlight if caret is on this line
+    if draw_highlight ~= false and config.highlight_current_line
+    and line1 == line and core.active_view == self then
+      draw_highlight = (line1 == line2 and col1 == col2)
+    end
+  end
+  if draw_highlight then 
+    local _, _, count = get_line_idx_col_count(self, line)
+    for i=1,count do 
+      self:draw_line_highlight(x + self.scroll.x, y + lh * (i - 1))
+    end
+  end
+  -- draw line's text
+  return self:draw_line_text(line, x, y)
+end
+
+local old_draw = DocView.draw
+function DocView:draw()
+  old_draw(self)
+  if self.wrapped_settings then
+    LineWrapping.draw_guide(self) 
+  end
+end 
+
+local old_draw_line_gutter = DocView.draw_line_gutter
+function DocView:draw_line_gutter(line, x, y, width)
+  local lh = self:get_line_height()
+  local _, _, count = get_line_idx_col_count(self, line)
+  return (old_draw_line_gutter(self, line, x, y, width) or lh) * count
+end
+
+local old_translate_end_of_line = translate.end_of_line
+function translate.end_of_line(doc, line, col)
+  if not core.active_view or core.active_view.doc ~= doc or not core.active_view.wrapped_settings then old_translate_end_of_line(doc, line, col) end
+  local idx, ncol = get_line_idx_col_count(core.active_view, line, col)
+  local nline, ncol2 = get_idx_line_col(core.active_view, idx + 1)
+  if nline ~= line then return line, math.huge end
+  return line, ncol2 - 1
+end
+
+local old_translate_start_of_line = translate.start_of_line
+function translate.start_of_line(doc, line, col)
+  if not core.active_view or core.active_view.doc ~= doc or not core.active_view.wrapped_settings then old_translate_start_of_line(doc, line, col) end
+  local idx, ncol = get_line_idx_col_count(core.active_view, line, col)
+  local nline, ncol2 = get_idx_line_col(core.active_view, idx - 1)
+  if nline ~= line then return line, 1 end
+  return line, ncol2 + 1
+end
+
+local old_previous_line = DocView.translate.previous_line
+function DocView.translate.previous_line(doc, line, col, dv)
+  if not dv.wrapped_settings then return old_previous_line(doc, line, col, dv) end
+  local idx, ncol = get_line_idx_col_count(dv, line, col)
+  return get_line_col_from_index_and_x(dv, idx - 1, dv:get_col_x_offset(line, col))
+end
+
+local old_next_line = DocView.translate.next_line
+function DocView.translate.next_line(doc, line, col, dv)
+  if not dv.wrapped_settings then return old_next_line(doc, line, col, dv) end
+  local idx, ncol = get_line_idx_col_count(dv, line, col)
+  return get_line_col_from_index_and_x(dv, idx + 1, dv:get_col_x_offset(line, col))
+end
+
+command.add(nil, {
+  ["line-wrapping:enable"] = function() 
+    if core.active_view and core.active_view.doc then 
+      LineWrapping.update_docview_breaks(core.active_view)
+    end
+  end,
+  ["line-wrapping:disable"] = function() 
+    if core.active_view and core.active_view.doc then 
+      LineWrapping.reconstruct_breaks(core.active_view, core.active_view:get_font(), math.huge)
+    end
+  end,
+  ["line-wrapping:toggle"] = function() 
+    if core.active_view and core.active_view.doc and core.active_view.wrapped_settings then 
+      command.perform("line-wrapping:disable")
+    else
+      command.perform("line-wrapping:enable")
+    end
+  end
+})
+
+keymap.add {
+  ["f10"] = "line-wrapping:toggle",
+}
+
+return LineWrapping