From e346128d4d8e76aedb47a490b491c64205478319 Mon Sep 17 00:00:00 2001
From: Lars Mueller <appgurulars@gmx.de>
Date: Wed, 19 Jan 2022 17:24:29 +0100
Subject: [PATCH] Add web.uri.encode[_component]

---
 test.lua     |  6 ++++--
 web.lua      | 35 +++++++----------------------------
 web/html.lua | 27 +++++++++++++++++++++++++++
 web/uri.lua  | 42 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 80 insertions(+), 30 deletions(-)
 create mode 100644 web/html.lua
 create mode 100644 web/uri.lua

diff --git a/test.lua b/test.lua
index 5031a48..cf8cc09 100644
--- a/test.lua
+++ b/test.lua
@@ -367,8 +367,10 @@ do
 	local text = "<tag> & '\""
 	local escaped = web.html.escape(text)
 	assert(web.html.unescape(escaped) == text)
-	assert(web.html.unescape("&#42;") == _G.string.char(42))
-	assert(web.html.unescape("&#x42;") == _G.string.char(0x42))
+	assert(web.html.unescape"&#42;" == _G.string.char(42))
+	assert(web.html.unescape"&#x42;" == _G.string.char(0x42))
+	assert(web.uri.encode"https://example.com/foo bar" == "https://example.com/foo%20bar")
+	assert(web.uri.encode_component"foo/bar baz" == "foo%2Fbar%20baz")
 end
 
 if not _G.minetest then return end
diff --git a/web.lua b/web.lua
index dafcbd2..4a1ba97 100644
--- a/web.lua
+++ b/web.lua
@@ -1,28 +1,7 @@
--- TODO incorporate https://github.com/minetest/minetest/pull/11578
-return {
-	html = setmetatable({
-		escape = function(text)
-			return text:gsub(".", {
-				["<"] = "&lt;",
-				[">"] = "&gt;",
-				["&"] = "&amp;",
-				["'"] = "&apos;",
-				['"'] = "&quot;",
-			})
-		end
-	}, {__index = function(self, key)
-		if key == "unescape" then
-			local func = assert(loadfile(modlib.mod.get_resource("modlib", "web", "html", "entities.lua")))
-			setfenv(func, {})
-			local named_entities = assert(func())
-			local function unescape(text)
-				return text
-					:gsub("&([A-Za-z]+);", named_entities) -- named
-					:gsub("&#(%d+);", function(digits) return modlib.text.utf8(tonumber(digits)) end) -- decimal
-					:gsub("&#x(%x+);", function(digits) return modlib.text.utf8(tonumber(digits, 16)) end) -- hex
-			end
-			self.unescape = unescape
-			return unescape
-		end
-	end})
-}
\ No newline at end of file
+return setmetatable({}, {__index = function(self, module_name)
+	if module_name == "uri" or module_name == "html" then
+		local module = assert(loadfile(modlib.mod.get_resource(modlib.modname, "web", module_name .. ".lua")))()
+		self[module_name] = module
+		return module
+	end
+end})
\ No newline at end of file
diff --git a/web/html.lua b/web/html.lua
new file mode 100644
index 0000000..f1b9aad
--- /dev/null
+++ b/web/html.lua
@@ -0,0 +1,27 @@
+local html = setmetatable({}, {__index = function(self, key)
+	if key == "unescape" then
+		local func = assert(loadfile(modlib.mod.get_resource("modlib", "web", "html", "entities.lua")))
+		setfenv(func, {})
+		local named_entities = assert(func())
+		local function unescape(text)
+			return text
+				:gsub("&([A-Za-z]+);", named_entities) -- named
+				:gsub("&#(%d+);", function(digits) return modlib.text.utf8(tonumber(digits)) end) -- decimal
+				:gsub("&#x(%x+);", function(digits) return modlib.text.utf8(tonumber(digits, 16)) end) -- hex
+		end
+		self.unescape = unescape
+		return unescape
+	end
+end})
+
+function html.escape(text)
+	return text:gsub(".", {
+		["<"] = "&lt;",
+		[">"] = "&gt;",
+		["&"] = "&amp;",
+		["'"] = "&apos;",
+		['"'] = "&quot;",
+	})
+end
+
+return html
\ No newline at end of file
diff --git a/web/uri.lua b/web/uri.lua
new file mode 100644
index 0000000..87e6aca
--- /dev/null
+++ b/web/uri.lua
@@ -0,0 +1,42 @@
+-- URI escaping utilities
+-- See https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURI
+
+local uri_unescaped_chars = {}
+for char in ("-_.!~*'()"):gmatch(".") do
+	uri_unescaped_chars[char] = true
+end
+local function add_unescaped_range(from, to)
+	for byte = from:byte(), to:byte() do
+		uri_unescaped_chars[string.char(byte)] = true
+	end
+end
+add_unescaped_range("0", "9")
+add_unescaped_range("a", "z")
+add_unescaped_range("A", "Z")
+
+local uri_allowed_chars = table.copy(uri_unescaped_chars)
+for char in (";,/?:@&=+$#"):gmatch(".") do
+	-- Reserved characters are allowed
+	uri_allowed_chars[char] = true
+end
+
+local function encode(text, allowed_chars)
+	return text:gsub(".", function(char)
+		if allowed_chars[char] then
+			return char
+		end
+		return ("%%%02X"):format(char:byte())
+	end)
+end
+
+local uri = {}
+
+function uri.encode_component(text)
+	return encode(text, uri_unescaped_chars)
+end
+
+function uri.encode(text)
+	return encode(text, uri_allowed_chars)
+end
+
+return uri
\ No newline at end of file