lua: move non-core code out of vis.lua

The following structure is adapted:

 * visrc.lua entry point for all Lua code

 * vis.lua only implements the Lua part of the core API

 * vis-std.lua registers standard event handlers (e.g. syntax highlighting,
   statusbar handling, theme changes etc). It is sourced from vis.lua.

 * plugins/* non essential editor functionality, needs to be explicitly
   enabled by loading it from visrc.lua

1 files changed, 119 insertions, 0 deletions

diff --git a/lua/vis-std.lua b/lua/vis-std.lua
new file mode 100644
index 0000000..d8a32ad
--- /dev/null
+++ b/lua/vis-std.lua
@@ -0,0 +1,119 @@
+-- standard vis event handlers
+
+vis.events.theme_change = function(name)
+	if name ~= nil then
+		local theme = 'themes/'..name
+		package.loaded[theme] = nil
+		require(theme)
+	end
+
+	if vis.lexers ~= nil then vis.lexers.lexers = {} end
+
+	for win in vis:windows() do
+		win.syntax = win.syntax;
+	end
+end
+
+vis.events.win_syntax = function(win, name)
+	local lexers = vis.lexers
+	if not lexers.load then return false end
+
+	win:style_define(win.STYLE_DEFAULT, lexers.STYLE_DEFAULT)
+	win:style_define(win.STYLE_CURSOR, lexers.STYLE_CURSOR)
+	win:style_define(win.STYLE_CURSOR_PRIMARY, lexers.STYLE_CURSOR_PRIMARY)
+	win:style_define(win.STYLE_CURSOR_LINE, lexers.STYLE_CURSOR_LINE)
+	win:style_define(win.STYLE_SELECTION, lexers.STYLE_SELECTION)
+	win:style_define(win.STYLE_LINENUMBER, lexers.STYLE_LINENUMBER)
+	win:style_define(win.STYLE_COLOR_COLUMN, lexers.STYLE_COLOR_COLUMN)
+
+	if name == nil then return true end
+
+	local lexer = lexers.load(name)
+	if not lexer then return false end
+
+	for token_name, id in pairs(lexer._TOKENSTYLES) do
+		local style = lexers['STYLE_'..string.upper(token_name)] or lexer._EXTRASTYLES[token_name]
+		win:style_define(id, style)
+	end
+
+	return true
+end
+
+vis.events.win_highlight = function(win, horizon_max)
+	if win.syntax == nil or vis.lexers == nil then return end
+	local lexer = vis.lexers.load(win.syntax)
+	if lexer == nil then return end
+
+	-- TODO: improve heuristic for initial style
+	local viewport = win.viewport
+	if not viewport then return end
+	local horizon = viewport.start < horizon_max and viewport.start or horizon_max
+	local view_start = viewport.start
+	local lex_start = viewport.start - horizon
+	local token_start = lex_start
+	viewport.start = token_start
+	local data = win.file:content(viewport)
+	local token_styles = lexer._TOKENSTYLES
+	local tokens = lexer:lex(data, 1)
+
+	for i = 1, #tokens, 2 do
+		local token_end = lex_start + tokens[i+1] - 1
+		if token_end >= view_start then
+			local name = tokens[i]
+			local style = token_styles[name]
+			if style ~= nil then
+				win:style(style, token_start, token_end)
+			end
+		end
+		token_start = token_end
+	end
+end
+
+local modes = {
+	[vis.MODE_NORMAL] = '',
+	[vis.MODE_OPERATOR_PENDING] = '',
+	[vis.MODE_VISUAL] = 'VISUAL',
+	[vis.MODE_VISUAL_LINE] = 'VISUAL-LINE',
+	[vis.MODE_INSERT] = 'INSERT',
+	[vis.MODE_REPLACE] = 'REPLACE',
+}
+
+vis.events.win_status = function(win)
+	local left_parts = {}
+	local right_parts = {}
+	local file = win.file
+	local cursor = win.cursor
+
+	local mode = modes[vis.mode]
+	if mode ~= '' and vis.win == win then
+		table.insert(left_parts, mode)
+	end
+
+	table.insert(left_parts, (file.name or '[No Name]') ..
+		(file.modified and ' [+]' or '') .. (vis.recording and ' @' or ''))
+
+	if file.newlines == "crlf" then
+		table.insert(right_parts, "␍␊")
+	end
+
+	if #win.cursors > 1 then
+		table.insert(right_parts, cursor.number..'/'..#win.cursors)
+	end
+
+	local size = file.size
+	table.insert(right_parts, (size == 0 and "0" or math.ceil(cursor.pos/size*100)).."%")
+
+	if not win.large then
+		local col = cursor.col
+		table.insert(right_parts, cursor.line..', '..col)
+		if size > 33554432 or col > 65536 then
+			win.large = true
+		end
+	end
+
+	local left = ' ' .. table.concat(left_parts, " » ") .. ' '
+	local right = ' ' .. table.concat(right_parts, " « ") .. ' '
+	win:status(left, right);
+end
+
+vis:command("set theme ".. (vis.ui.colors <= 16 and "default-16" or "default-256"))