--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/luan_editor/find.luan	Mon Apr 21 13:07:29 2025 -0600
@@ -0,0 +1,244 @@
+local Luan = require "luan:Luan.luan"
+local error = Luan.error
+local ipairs = Luan.ipairs or error()
+local range = Luan.range or error()
+local String = require "luan:String.luan"
+local regex = String.regex or error()
+local regex_quote = String.regex_quote or error()
+local regex_quote_replacement = String.regex_quote_replacement or error()
+local repeated = String.repeated or error()
+local new_text_field = require("luan:swing/Text_field.luan").new or error()
+local new_check_box = require("luan:swing/Check_box.luan").new or error()
+local new_label = require("luan:swing/Label.luan").new or error()
+local new_panel = require("luan:swing/Component.luan").new_panel or error()
+local Layout = require "luan:swing/Layout.luan"
+local new_mig_layout = Layout.new_mig_layout or error()
+local new_button = require("luan:swing/Button.luan").new or error()
+local Swing = require "luan:swing/Swing.luan"
+local browse = Swing.browse or error()
+
+
+local function get_matches(text,s)
+	local r = regex(s)
+	local matches = {}
+	local i = 1
+	local n = #text
+	while i <= n do
+		local j1, j2 = r.find(text,i)
+		if j1 == nil then
+			break
+		end
+		j2 = j2 + 1
+		if j1 == j2 then
+			i = j2 + 1
+		else
+			matches[#matches+1] = { start=j1, end_=j2 }
+			i = j2
+		end
+	end
+	return matches
+end
+
+local function make_find_panel(window)
+	local text_area = window.text_area
+	local status_bar = window.status_bar
+	local find_field, replace_field, regex_check_box
+	local function find_match(event)
+		--logger.info("action "..event.action)
+		local s = find_field.text
+		if #s == 0 then
+			status_bar.text = " "
+			return
+		end
+		if not regex_check_box.is_selected then
+			s = regex_quote(s)
+		end
+		local matches
+		try
+			matches = get_matches( text_area.text, s )
+		catch e
+			status_bar.text = "Regex error: "..e.get_message()
+			return
+		end
+		text_area.set_hightlights(matches)
+		local n_matches = #matches
+		if n_matches == 0 then
+			status_bar.text = "0 matches"
+			return
+		end
+		local action = event.action
+		if action == "next" then
+			local _, pos = text_area.get_selection()
+			for i, match in ipairs(matches) do
+				if match.start >= pos then
+					text_area.set_selection( match.start, match.end_ )
+					status_bar.text = i.." of "..n_matches.." matches"
+					return
+				end
+			end
+			local match = matches[1]
+			text_area.set_selection( match.start, match.end_ )
+			status_bar.text = "1 of "..n_matches.." matches; wrapped past end"
+		elseif action == "previous" then
+			local pos = text_area.get_selection()
+			for i in range(n_matches,1,-1) do
+				local match = matches[i]
+				if match.end_ <= pos then
+					text_area.set_selection( match.start, match.end_ )
+					status_bar.text = i.." of "..n_matches.." matches"
+					return
+				end
+			end
+			local match = matches[n_matches]
+			text_area.set_selection( match.start, match.end_ )
+			status_bar.text = n_matches.." of "..n_matches.." matches; wrapped past end"
+		else
+			error(action)
+		end
+	end
+	local function replace_match(event)
+		local find = find_field.text
+		if #find == 0 then
+			status_bar.text = " "
+			return
+		end
+		local replace = replace_field.text
+		if not regex_check_box.is_selected then
+			find = regex_quote(find)
+			replace = regex_quote_replacement(replace)
+		end
+		local r
+		try
+			r = regex(find)
+		catch e
+			status_bar.text = "Regex error: "..e.get_message()
+			return
+		end
+		local new, n
+		local action = event.action
+		if action == "replace" then
+			local selection = text_area.selected_text
+			new, n = r.gsub(selection,replace)
+			if n > 0 then
+				text_area.selected_text = new
+			end
+		elseif action == "replace_all" then
+			local text = text_area.text
+			new, n = r.gsub(text,replace)
+			if n > 0 then
+				text_area.text = new
+			end
+		else
+			error(action)
+		end
+		status_bar.text = n.." replacements"
+	end
+	find_field = new_text_field{
+		constraints = "growx"
+		whitespace_visible = true
+		action = "next"
+		action_listener = find_match
+	}
+	replace_field = new_text_field{
+		constraints = "growx"
+		whitespace_visible = true
+		action = "replace"
+		action_listener = replace_match
+	}
+	regex_check_box = new_check_box{
+		text = "Use Regex"
+	}
+	local find_panel = new_panel{
+		constraints = "growy 0,growx"
+		layout = new_mig_layout("insets 8 16 0 16","[][grow][grow 0]")
+		visible = false
+		children = {
+			new_label{
+				constraints = "right"
+				text = "Find:"
+			}
+			find_field
+			new_button{
+				constraints = "grow"
+				text = "Find Next"
+				action = "next"
+				action_listener = find_match
+			}
+			new_button{
+				constraints = "grow,wrap"
+				text = "Find Previous"
+				action = "previous"
+				action_listener = find_match
+			}
+			new_label{
+				constraints = "right"
+				text = "Replace:"
+			}
+			replace_field
+			new_button{
+				constraints = "grow"
+				text = "Replace"
+				tool_tip_text = "Replace matches in selected text"
+				action = "replace"
+				action_listener = replace_match
+			}
+			new_button{
+				constraints = "grow,wrap"
+				text = "Replace All"
+				action = "replace_all"
+				action_listener = replace_match
+			}
+			new_panel{
+				constraints = "span,wrap"
+				layout = new_mig_layout("insets 0,gap 16px")
+				children = {
+					regex_check_box
+					new_button{
+						text = "Learn About Regular Expressions"
+						action_listener = function(_)
+							browse("https://www.reactionary.software/learn.html#regex")
+						end
+					}
+				}
+			}
+		}
+	}
+	function window.show_find_panel(visible)
+		find_panel.visible = visible
+		if visible then
+			find_field.request_focus_in_window()
+		else
+			text_area.clear_hightlights()
+		end
+	end
+	function window.find_case_insensitive(_)
+		find_panel.visible = true
+		window.find_menu_item.is_selected = true
+		regex_check_box.is_selected = true
+		find_field.text = "(?i)\Q\E"
+		find_field.set_selection(7)
+		find_field.request_focus_in_window()
+		status_bar.text = [[Put search text between "\Q" and "\E"]]
+	end
+	function window.tabs_to_spaces(_)
+		find_panel.visible = true
+		window.find_menu_item.is_selected = true
+		regex_check_box.is_selected = true
+		find_field.text = [[(?m)^(\t*)\t]]
+		local spaces = repeated( " ", text_area.tab_size )
+		replace_field.text = "$1"..spaces
+		status_bar.text = [[Do "Replace All" until 0 replacements]]
+	end
+	function window.spaces_to_tabs(_)
+		find_panel.visible = true
+		window.find_menu_item.is_selected = true
+		regex_check_box.is_selected = true
+		local tab_size = text_area.tab_size
+		find_field.text = `%>(?m)^(( {<%=tab_size%>})*) {<%=tab_size%>}<%`
+		replace_field.text = "$1\t"
+		status_bar.text = [[Do "Replace All" until 0 replacements]]
+	end
+	return find_panel
+end
+
+return make_find_panel