fragment | Implement better autocmd management | refactor

add a all_buffers option - colorizer will activate on all buffers, empty or not, still respect filetypes option

handle errors when detach is called multiple times from the same buffer

use bufdelete and bufdelete to remove the autocmds

use a more efficient compile parse_fn function

use custom ldoc template to generate vim help

1 files changed, 196 insertions, 0 deletions

diff --git a/lua/colorizer/buffer_utils.lua b/lua/colorizer/buffer_utils.lua
new file mode 100644
index 0000000..0f8517f
--- /dev/null
+++ b/lua/colorizer/buffer_utils.lua
@@ -0,0 +1,196 @@
+---Helper functions to highlight buffer smartly
+--@module colorizer.buffer_utils
+local api = vim.api
+local buf_set_virtual_text = api.nvim_buf_set_extmark
+local buf_get_lines = api.nvim_buf_get_lines
+local create_namespace = api.nvim_create_namespace
+local clear_namespace = api.nvim_buf_clear_namespace
+local set_highlight = api.nvim_set_hl
+
+local color_utils = require "colorizer.color_utils"
+local color_is_bright = color_utils.color_is_bright
+
+local matcher_utils = require "colorizer.matcher_utils"
+local make_matcher = matcher_utils.make_matcher
+
+--- Default namespace used in `highlight_buffer` and `colorizer.attach_to_buffer`.
+-- @see highlight_buffer
+-- @see colorizer.attach_to_buffer
+local DEFAULT_NAMESPACE = create_namespace "colorizer"
+local HIGHLIGHT_NAME_PREFIX = "colorizer"
+--- Highlight mode which will be use to render the colour
+local HIGHLIGHT_MODE_NAMES = {
+  background = "mb",
+  foreground = "mf",
+  virtualtext = "mv",
+}
+local HIGHLIGHT_CACHE = {}
+
+--- Make a deterministic name for a highlight given these attributes
+local function make_highlight_name(rgb, mode)
+  return table.concat({ HIGHLIGHT_NAME_PREFIX, HIGHLIGHT_MODE_NAMES[mode], rgb }, "_")
+end
+
+local function create_highlight(rgb_hex, options)
+  local mode = options.mode or "background"
+  -- TODO validate rgb format?
+  rgb_hex = rgb_hex:lower()
+  local cache_key = table.concat({ HIGHLIGHT_MODE_NAMES[mode], rgb_hex }, "_")
+  local highlight_name = HIGHLIGHT_CACHE[cache_key]
+
+  -- Look up in our cache.
+  if highlight_name then
+    return highlight_name
+  end
+
+  -- convert from #fff to #ffffff
+  if #rgb_hex == 3 then
+    rgb_hex = table.concat {
+      rgb_hex:sub(1, 1):rep(2),
+      rgb_hex:sub(2, 2):rep(2),
+      rgb_hex:sub(3, 3):rep(2),
+    }
+  end
+
+  -- Create the highlight
+  highlight_name = make_highlight_name(rgb_hex, mode)
+  if mode == "foreground" then
+    set_highlight(0, highlight_name, { fg = "#" .. rgb_hex })
+  else
+    local rr, gg, bb = rgb_hex:sub(1, 2), rgb_hex:sub(3, 4), rgb_hex:sub(5, 6)
+    local r, g, b = tonumber(rr, 16), tonumber(gg, 16), tonumber(bb, 16)
+    local fg_color
+    if color_is_bright(r, g, b) then
+      fg_color = "Black"
+    else
+      fg_color = "White"
+    end
+    set_highlight(0, highlight_name, { fg = fg_color, bg = "#" .. rgb_hex })
+  end
+  HIGHLIGHT_CACHE[cache_key] = highlight_name
+  return highlight_name
+end
+
+local function add_highlight(options, buf, ns, data)
+  if vim.tbl_contains({ "foreground", "background" }, options.mode) then
+    for linenr, hls in pairs(data) do
+      for _, hl in ipairs(hls) do
+        api.nvim_buf_add_highlight(buf, ns, hl.name, linenr, hl.range[1], hl.range[2])
+      end
+    end
+  elseif options.mode == "virtualtext" then
+    for linenr, hls in pairs(data) do
+      for _, hl in ipairs(hls) do
+        buf_set_virtual_text(0, ns, linenr, hl.range[2], {
+          end_col = hl.range[2],
+          virt_text = { { options.virtualtext or "■", hl.name } },
+        })
+      end
+    end
+  end
+end
+
+--- Highlight the buffer region.
+-- Highlight starting from `line_start` (0-indexed) for each line described by `lines` in the
+-- buffer `buf` and attach it to the namespace `ns`.
+---@param buf number: buffer id
+---@param ns number: The namespace id. Default is DEFAULT_NAMESPACE. Create it with `vim.api.create_namespace`
+---@param lines table: the lines to highlight from the buffer.
+---@param line_start number: line_start should be 0-indexed
+---@param options table: Configuration options as described in `setup`
+local function highlight_buffer(buf, ns, lines, line_start, options)
+  if buf == 0 or buf == nil then
+    buf = api.nvim_get_current_buf()
+  end
+
+  ns = ns or DEFAULT_NAMESPACE
+  local loop_parse_fn = make_matcher(options)
+  if not loop_parse_fn then
+    return false
+  end
+
+  local data = {}
+  local mode = options.mode == "background" and { mode = "background" } or { mode = "foreground" }
+  for current_linenum, line in ipairs(lines) do
+    current_linenum = current_linenum - 1 + line_start
+    -- Upvalues are options and current_linenum
+    local i = 1
+    while i < #line do
+      local length, rgb_hex = loop_parse_fn(line, i)
+      if length then
+        local name = create_highlight(rgb_hex, mode)
+        local d = data[current_linenum] or {}
+        table.insert(d, { name = name, range = { i - 1, i + length - 1 } })
+        data[current_linenum] = d
+        i = i + length
+      else
+        i = i + 1
+      end
+    end
+  end
+  add_highlight(options, buf, ns, data)
+end
+
+local BUFFER_LINES = {}
+--- Rehighlight the buffer if colorizer is active
+---@param buf number: Buffer number
+---@param options table: Buffer options
+local function rehighlight_buffer(buf, options)
+  if buf == 0 or buf == nil then
+    buf = api.nvim_get_current_buf()
+  end
+
+  local ns = DEFAULT_NAMESPACE
+
+  if not BUFFER_LINES[buf] then
+    BUFFER_LINES[buf] = {}
+  end
+
+  local a = api.nvim_buf_call(buf, function()
+    return {
+      vim.fn.line "w0",
+      vim.fn.line "w$",
+    }
+  end)
+  local min, max
+  local new_min, new_max = a[1] - 1, a[2]
+  local old_min, old_max = BUFFER_LINES[buf]["min"], BUFFER_LINES[buf]["max"]
+
+  if old_min and old_max then
+    -- Triggered for TextChanged autocmds
+    -- TODO: Find a way to just apply highlight to changed text lines
+    if old_max == new_max then
+      min, max = new_min, new_max
+    -- Triggered for WinScrolled autocmd - Scroll Down
+    elseif old_max < new_max then
+      min = old_max
+      max = new_max
+    -- Triggered for WinScrolled autocmd - Scroll Up
+    elseif old_max > new_max then
+      min = new_min
+      max = new_min + (old_max - new_max)
+    end
+    -- just in case a long jump was made
+    if max - min > new_max - new_min then
+      min = new_min
+      max = new_max
+    end
+  end
+
+  min = min or new_min
+  max = max or new_max
+  clear_namespace(buf, ns, min, max)
+  local lines = buf_get_lines(buf, min, max, false)
+  highlight_buffer(buf, ns, lines, min, options)
+  -- store current window position to be used later to incremently highlight
+  BUFFER_LINES[buf]["max"] = new_max
+  BUFFER_LINES[buf]["min"] = new_min
+end
+
+--- @export
+return {
+  DEFAULT_NAMESPACE = DEFAULT_NAMESPACE,
+  HIGHLIGHT_MODE_NAMES = HIGHLIGHT_MODE_NAMES,
+  rehighlight_buffer = rehighlight_buffer,
+  highlight_buffer = highlight_buffer,
+}