require('vis')

local m = vis.modes
local mode_strings = {
	[m.NORMAL]           = 'NORMAL',
	[m.OPERATOR_PENDING] = 'OPERATOR-PENDING',
	[m.VISUAL]           = 'VISUAL',
	[m.VISUAL_LINE]      = 'VISUAL-LINE',
	[m.INSERT]           = 'INSERT',
	[m.REPLACE]          = 'REPLACE',
}

local e = vis.events

-- init
e.subscribe(e.INIT, function()
	-- load theme
	require('themes/basic')

	-- mappings
	if os.getenv('WAYLAND_DISPLAY') then
		vis:map(m.NORMAL,      'y', '<vis-register>+<vis-operator-yank>')
		vis:map(m.VISUAL,      'y', '<vis-register>+<vis-operator-yank>')
		vis:map(m.NORMAL,      'y', '<vis-register>+<vis-operator-yank>')
		vis:map(m.VISUAL,      'd', '<vis-register>+<vis-operator-delete>')
		vis:map(m.VISUAL_LINE, 'd', '<vis-register>+<vis-operator-delete>')
		vis:map(m.VISUAL_LINE, 'd', '<vis-register>+<vis-operator-delete>')
		vis:map(m.NORMAL,      'p', '<vis-register>+<vis-put-after>')
		vis:map(m.VISUAL,      'p', '<vis-register>+<vis-put-after>')
		vis:map(m.VISUAL_LINE, 'p', '<vis-register>+<vis-put-after>')
		vis:map(m.NORMAL,      'P', '<vis-register>+<vis-put-before>')
		vis:map(m.VISUAL,      'P', '<vis-register>+<vis-put-before>')
		vis:map(m.VISUAL_LINE, 'P', '<vis-register>+<vis-put-before>')
	end

	vis:map(m.NORMAL,           'f', '<vis-selections-save><vis-motion-to-right>')
	vis:map(m.OPERATOR_PENDING, 'f', '<vis-motion-to-right>')
	vis:map(m.VISUAL,           'f', '<vis-motion-to-right>')
	vis:map(m.NORMAL,           'F', '<vis-selections-save><vis-motion-to-left>')
	vis:map(m.OPERATOR_PENDING, 'F', '<vis-motion-to-left>')
	vis:map(m.VISUAL,           'F', '<vis-motion-to-left>')
	vis:map(m.NORMAL,           't', '<vis-selections-save><vis-motion-till-right>')
	vis:map(m.OPERATOR_PENDING, 't', '<vis-motion-till-right>')
	vis:map(m.VISUAL,           't', '<vis-motion-till-right>')
	vis:map(m.NORMAL,           'T', '<vis-selections-save><vis-motion-till-left>')
	vis:map(m.OPERATOR_PENDING, 'T', '<vis-motion-till-left>')
	vis:map(m.VISUAL,           'T', '<vis-motion-till-left>')

	vis:map(m.NORMAL, '?', '<vis-selections-save><vis-search-backward>')
	vis:map(m.NORMAL, '/', '<vis-selections-save><vis-search-forward>')

	vis:map(m.NORMAL, 'zz', '<vis-window-redraw-bottom><vis-window-redraw-center>') -- fixes a bug with `zz`

	vis:map(m.NORMAL, ' w', function() vis:command('w') end)
	vis:map(m.NORMAL, ' W', function() vis:command('w!') end)
	vis:map(m.NORMAL, ' q', function() vis:command('q') end)
	vis:map(m.NORMAL, ' Q', function() vis:command('q!') end)

	vis:map(m.NORMAL, ' e', function()
		local s, f = vis:pipe('find -name .git -prune -o -type f | vis-menu -l 5 -p "Edit file"')
		if s ~= 0 or f == nil then return end
		cmd = ('e "%s"'):format(f:sub(1, -2))
		vis:info(cmd)
		vis:command(cmd)
	end, 'Edit file')

	vis:map(m.NORMAL, ' o', function()
		local s, f = vis:pipe('find -name .git -prune -o -type f | vis-menu -l 5 -p "Open file"')
		if s ~= 0 or f == nil then return end
		cmd = ('o "%s"'):format(f:sub(1, -2))
		vis:info(cmd)
		vis:command(cmd)
	end, 'Open file')

	vis:map(m.NORMAL, ' cd', function()
		local s, f = vis:pipe('find -name .git -prune -o -type d | vis-menu -l 5 -p "Change directory"')
		if s ~= 0 or f == nil then return end
		cmd = ('cd "%s"'):format(f:sub(1, -2))
		vis:info(cmd)
		vis:command(cmd)
	end, 'Change directory')

	-- editor options
	vis.options.autoindent = true
end)

-- window open
e.subscribe(e.WIN_OPEN, function(win)
	win.options.colorcolumn = 81
	win.options.numbers = true

	if win.syntax == 'markdown' then
		win.options.breakat = ' ,]_'
		win.options.expandtab = true
		win.options.tabwidth = 2
		win.options.wrapcolumn = 80
	end

	if win.syntax == 'css' then
		win.options.expandtab = true
		win.options.tabwidth = 2
	end
end)

-- statusline
e.subscribe(e.WIN_STATUS, function(win)
	local left_parts = {}
	local right_parts = {}
	local file = win.file
	local selection = win.selection

	-- file info
	table.insert(left_parts,
		(file.name or '[No Name]')..(file.modified and '[+]' or ''))

	-- selection
	table.insert(right_parts, selection.number..'/'..#win.selections)

	if vis.win == win then
		-- mode
		table.insert(left_parts, 1, mode_strings[vis.mode])

		-- syntax
		table.insert(left_parts, win.syntax)

		-- input info
		table.insert(left_parts,
			'<'
			..(vis.count or '')
			..(vis.input_queue or '')
			..(vis.recording and '@' or '')
			..'>')

		-- character under cursor
		table.insert(right_parts,
			'<'
			..(file:content(selection and selection.pos or 0, 1):byte() or 'nil')
			..'>')

		-- line and column count
		table.insert(right_parts, #file.lines..'/'..selection.line)
		table.insert(right_parts, selection.col)
	end

	-- fillchars
	local left = table.concat(left_parts, ' ')
	local right = table.concat(right_parts, ' ')

	win:status(table.concat({ left, ('^'):rep(win.width - #left - #right - 2)}, ' '), right)
end)

-- set title
local modified = false
local function set_title(name)
	os.execute(('printf "\\e];%s%s\\e"'):format(name, modified and '[+]' or ''))
end

if os.getenv('TERM') ~= 'linux' then
	e.subscribe(e.WIN_OPEN, function(win)
		set_title(win.file.name or '[No Name]')
	end)

	e.subscribe(e.FILE_SAVE_POST, function(file)
		modified = false
		set_title(file.name)
	end)

	e.subscribe(e.WIN_STATUS, function(win)
		if not modified and win.file.modified then
			modified = true
			set_title(win.file.name or '[No Name]')
		end
	end)
end

-- cursor position
local cursors_path = os.getenv('XDG_CACHE_HOME')..'/vis-cursors'
local cursors = {}
local files = {}

local function get_cursors()
	local f = io.open(cursors_path)
	if f == nil then return end
	files = {}
	for l in f:lines() do
		local path, pos = l:match('(.+):(%d+)')
		cursors[path] = pos
		table.insert(files, path)
	end
	f:close()
end

e.subscribe(e.INIT, get_cursors)

e.subscribe(e.WIN_OPEN, function(win)
	if win.file == nil or win.file.path == nil then return end
	if win.file.path:match('%.git/COMMIT_EDITMSG$') then return end
	if win.file.path:match('^/tmp/') then return end
	local pos = cursors[win.file.path]
	if pos == nil then
		cursors[win.file.path] = win.selection.pos
		return
	end
	win.selection.pos = tonumber(pos)
	vis:feedkeys('zz')
end)

e.subscribe(e.WIN_CLOSE, function(win)
	if win.file == nil or win.file.path == nil then return end
	get_cursors()
	for i, path in ipairs(files) do
		if path == win.file.path then table.remove(files, i) end
	end
	if win.selection.pos == 0 then return end
	table.insert(files, 1, win.file.path)
	cursors[win.file.path] = win.selection.pos
end)

e.subscribe(e.QUIT, function()
	local f = io.open(cursors_path, 'w+')
	if f == nil then return end
	local buf = {}
	for i, path in ipairs(files) do
		table.insert(buf, ('%s:%d'):format(path, cursors[path]))
		if i > 100 then break end -- remember only 100
	end
	local out = table.concat(buf, '\n')
	f:write(out)
	f:close()
end)