move generic menu operations to metatable

1 files changed, 112 insertions, 2 deletions

diff --git a/state.lua b/state.lua
index 472e4d2..2f609c9 100644
--- a/state.lua
+++ b/state.lua
@@ -1,9 +1,14 @@
 -- Copyright 2025 David Vazgenovich Shakaryan
 
+local util = require('util')
+
 local state = {}
 local mt = {}
 mt.__index = mt
 
+local menu_mt = {}
+menu_mt.__index = menu_mt
+
 function state.new()
 	return setmetatable({
 		menus = {},
@@ -19,18 +24,28 @@ function mt:menu()
 end
 
 function mt:push_menu(t)
-	local menu = {
+	local menu = setmetatable({
 		options = {},
 		cursor = 1,
 		view_top = 1,
-	}
+	}, menu_mt)
 
 	for k, v in pairs(t) do
 		menu[k] = v
 	end
 
+	if menu.type == 'search' then
+		menu.search_options = menu.options
+		menu.search_text = menu.search_text or ''
+		menu.search_cursor = menu.search_cursor or
+			#menu.search_text + 1
+		menu:update_search_matches()
+	end
+
 	self.depth = self.depth + 1
 	self.menus[self.depth] = menu
+
+	return menu
 end
 
 -- returns index if found
@@ -67,4 +82,99 @@ function mt:insert_favourite_before_next_in_menu(id)
 	self:add_favourite(id)
 end
 
+function menu_mt:set_cursor(pos, lines, opts)
+	local pos = math.max(1, math.min(pos, #self.options))
+	local top = self.view_top
+	if opts and opts.centre then
+		top = pos - math.floor((lines - 1) / 2)
+	elseif opts and opts.keep_offset then
+		top = top + pos - self.cursor
+	end
+
+	-- move view to keep selected option visible
+	if pos < top then
+		top = pos
+	elseif pos > top + lines - 1 then
+		top = pos - lines + 1
+	end
+
+	top = math.max(1, math.min(top, #self.options - lines + 1))
+
+	self.cursor = pos
+	self.view_top = top
+end
+
+function menu_mt:set_sort(bool, f)
+	if not self.sorted == not bool then
+		return
+	end
+
+	local key = self.type == 'search' and 'search_options' or 'options'
+	if bool then
+		self['orig_' .. key] = self[key]
+		self[key] = util.copy_table(self[key])
+		f(self[key])
+	else
+		self[key] = self['orig_' .. key]
+		self['orig_' .. key] = nil
+	end
+
+	if self.type == 'search' then
+		self:update_search_matches()
+	end
+	self.sorted = bool
+end
+
+function menu_mt:set_search_cursor(pos)
+	local pos = math.max(1, math.min(#self.search_text + 1, pos))
+	if pos == self.search_cursor then
+		return false
+	end
+
+	self.search_cursor = pos
+	return true
+end
+
+function menu_mt:set_search_text(str)
+	self.search_text = str
+	self:update_search_matches()
+end
+
+function menu_mt:update_search_matches()
+	if #self.search_text == 0 then
+		self.options = self.search_options
+		return
+	end
+
+	-- no utf8 :(
+	local case_sensitive = not not self.search_text:find('%u')
+
+	local options = {}
+	for _, v in ipairs(self.search_options) do
+		local matches = {}
+
+		local name = v.name
+		if not case_sensitive then
+			name = name:lower()
+		end
+
+		local i, j = 0, 0
+		while true do
+			i, j = name:find(self.search_text, j + 1, true)
+			if not i then
+				break
+			end
+			matches[#matches+1] = {start = i, stop = j}
+		end
+
+		if #matches > 0 then
+			local t = util.copy_table(v)
+			t.matches = matches
+			options[#options+1] = t
+		end
+	end
+
+	self.options = options
+end
+
 return state