-- Minetest: builtin/chatcommands.lua

--
-- Chat command handler
--

minetest.chatcommands = {}
function minetest.register_chatcommand(cmd, def)
	def = def or {}
	def.params = def.params or ""
	def.description = def.description or ""
	def.privs = def.privs or {}
	minetest.chatcommands[cmd] = def
end

minetest.register_on_chat_message(function(name, message)
	local cmd, param = string.match(message, "/([^ ]+) *(.*)")
	if not param then
		param = ""
	end
	local cmd_def = minetest.chatcommands[cmd]
	if cmd_def then
		if not cmd_def.func then
			-- This is a C++ command
			return false
		else
			local has_privs, missing_privs = minetest.check_player_privs(name, cmd_def.privs)
			if has_privs then
				cmd_def.func(name, param)
			else
				minetest.chat_send_player(name, "You don't have permission to run this command (missing privileges: "..table.concat(missing_privs, ", ")..")")
			end
			return true -- handled chat message
		end
	end
	return false
end)

--
-- Chat commands
--

-- Register C++ commands without functions
minetest.register_chatcommand("me", {params = nil, description = "chat action (eg. /me orders a pizza)"})
minetest.register_chatcommand("status", {description = "print server status line"})
minetest.register_chatcommand("shutdown", {params = "", description = "shutdown server", privs = {server=true}})
minetest.register_chatcommand("clearobjects", {params = "", description = "clear all objects in world", privs = {server=true}})
minetest.register_chatcommand("time", {params = "<0...24000>", description = "set time of day", privs = {settime=true}})
minetest.register_chatcommand("ban", {params = "<name>", description = "ban IP of player", privs = {ban=true}})
minetest.register_chatcommand("unban", {params = "<name/ip>", description = "remove IP ban", privs = {ban=true}})

-- Register other commands
minetest.register_chatcommand("help", {
	privs = {},
	params = "(nothing)/all/privs/<cmd>",
	description = "Get help for commands or list privileges",
	func = function(name, param)
		local format_help_line = function(cmd, def)
			local msg = "/"..cmd
			if def.params and def.params ~= "" then msg = msg .. " " .. def.params end
			if def.description and def.description ~= "" then msg = msg .. ": " .. def.description end
			return msg
		end
		if param == "" then
			local msg = ""
			cmds = {}
			for cmd, def in pairs(minetest.chatcommands) do
				if minetest.check_player_privs(name, def.privs) then
					table.insert(cmds, cmd)
				end
			end
			minetest.chat_send_player(name, "Available commands: "..table.concat(cmds, " "))
			minetest.chat_send_player(name, "Use '/help <cmd>' to get more information, or '/help all' to list everything.")
		elseif param == "all" then
			minetest.chat_send_player(name, "Available commands:")
			for cmd, def in pairs(minetest.chatcommands) do
				if minetest.check_player_privs(name, def.privs) then
					minetest.chat_send_player(name, format_help_line(cmd, def))
				end
			end
		elseif param == "privs" then
			minetest.chat_send_player(name, "Available privileges:")
			for priv, def in pairs(minetest.registered_privileges) do
				minetest.chat_send_player(name, priv..": "..def.description)
			end
		else
			local cmd = param
			def = minetest.chatcommands[cmd]
			if not def then
				minetest.chat_send_player(name, "Command not available: "..cmd)
			else
				minetest.chat_send_player(name, format_help_line(cmd, def))
			end
		end
	end,
})
minetest.register_chatcommand("privs", {
	params = "<name>",
	description = "print out privileges of player",
	func = function(name, param)
		if param == "" then
			param = name
		else
			if not minetest.check_player_privs(name, {privs=true}) then
				minetest.chat_send_player(name, "Privileges of "..param.." are hidden from you.")
			end
		end
		minetest.chat_send_player(name, "Privileges of "..param..": "..minetest.privs_to_string(minetest.get_player_privs(param), ' '))
	end,
})
minetest.register_chatcommand("grant", {
	params = "<name> <privilege>|all",
	description = "Give privilege to player",
	privs = {privs=true},
	func = function(name, param)
		local grantname, grantprivstr = string.match(param, "([^ ]+) (.+)")
		if not grantname or not grantprivstr then
			minetest.chat_send_player(name, "Invalid parameters (see /help grant)")
			return
		end
		local grantprivs = minetest.string_to_privs(grantprivstr)
		if grantprivstr == "all" then
			grantprivs = minetest.registered_privileges
		end
		local privs = minetest.get_player_privs(grantname)
		local privs_known = true
		for priv, _ in pairs(grantprivs) do
			if not minetest.registered_privileges[priv] then
				minetest.chat_send_player(name, "Unknown privilege: "..priv)
				privs_known = false
			end
			privs[priv] = true
		end
		if not privs_known then
			return
		end
		minetest.set_player_privs(grantname, privs)
		minetest.chat_send_player(name, "Privileges of "..grantname..": "..minetest.privs_to_string(minetest.get_player_privs(grantname), ' '))
		if grantname ~= name then
			minetest.chat_send_player(grantname, name.." granted you privileges: "..minetest.privs_to_string(grantprivs, ' '))
		end
	end,
})
minetest.register_chatcommand("revoke", {
	params = "<name> <privilege>|all",
	description = "Remove privilege from player",
	privs = {privs=true},
	func = function(name, param)
		local revokename, revokeprivstr = string.match(param, "([^ ]+) (.+)")
		if not revokename or not revokeprivstr then
			minetest.chat_send_player(name, "Invalid parameters (see /help revoke)")
			return
		end
		local revokeprivs = minetest.string_to_privs(revokeprivstr)
		local privs = minetest.get_player_privs(revokename)
		if revokeprivstr == "all" then
			privs = {}
		else
			for priv, _ in pairs(revokeprivs) do
				privs[priv] = nil
			end
		end
		minetest.set_player_privs(revokename, privs)
		minetest.chat_send_player(name, "Privileges of "..revokename..": "..minetest.privs_to_string(minetest.get_player_privs(revokename), ' '))
		if revokename ~= name then
			minetest.chat_send_player(revokename, name.." revoked privileges from you: "..minetest.privs_to_string(revokeprivs, ' '))
		end
	end,
})
minetest.register_chatcommand("setpassword", {
	params = "<name> <password>",
	description = "set given password",
	privs = {password=true},
	func = function(name, param)
		if param == "" then
			minetest.chat_send_player(name, "Password field required")
			return
		end
		minetest.set_player_password(name, param)
		minetest.chat_send_player(name, "Password set")
	end,
})
minetest.register_chatcommand("clearpassword", {
	params = "<name>",
	description = "set empty password",
	privs = {password=true},
	func = function(name, param)
		minetest.set_player_password(name, '')
		minetest.chat_send_player(name, "Password cleared")
	end,
})

minetest.register_chatcommand("auth_reload", {
	params = "",
	description = "reload authentication data",
	privs = {server=true},
	func = function(name, param)
		local done = minetest.auth_reload()
		if done then
			minetest.chat_send_player(name, "Done.")
		else
			minetest.chat_send_player(name, "Failed.")
		end
	end,
})

minetest.register_chatcommand("teleport", {
	params = "<X>,<Y>,<Z> | <to_name> | <name> <X>,<Y>,<Z> | <name> <to_name>",
	description = "teleport to given position",
	privs = {teleport=true},
	func = function(name, param)
		-- Returns (pos, true) if found, otherwise (pos, false)
		local function find_free_position_near(pos)
			local tries = {
				{x=1,y=0,z=0},
				{x=-1,y=0,z=0},
				{x=0,y=0,z=1},
				{x=0,y=0,z=-1},
			}
			for _, d in ipairs(tries) do
				local p = {x = pos.x+d.x, y = pos.y+d.y, z = pos.z+d.z}
				local n = minetest.env:get_node(p)
				if not minetest.registered_nodes[n.name].walkable then
					return p, true
				end
			end
			return pos, false
		end

		local teleportee = nil
		local p = {}
		p.x, p.y, p.z = string.match(param, "^([%d.-]+)[, ] *([%d.-]+)[, ] *([%d.-]+)$")
		teleportee = minetest.env:get_player_by_name(name)
		if teleportee and p.x and p.y and p.z then
			minetest.chat_send_player(name, "Teleporting to ("..p.x..", "..p.y..", "..p.z..")")
			teleportee:setpos(p)
			return
		end
		
		local teleportee = nil
		local p = nil
		local target_name = nil
		target_name = string.match(param, "^([^ ]+)$")
		teleportee = minetest.env:get_player_by_name(name)
		if target_name then
			local target = minetest.env:get_player_by_name(target_name)
			if target then
				p = target:getpos()
			end
		end
		if teleportee and p then
			p = find_free_position_near(p)
			minetest.chat_send_player(name, "Teleporting to "..target_name.." at ("..p.x..", "..p.y..", "..p.z..")")
			teleportee:setpos(p)
			return
		end
		
		if minetest.check_player_privs(name, {bring=true}) then
			local teleportee = nil
			local p = {}
			local teleportee_name = nil
			teleportee_name, p.x, p.y, p.z = string.match(param, "^([^ ]+) +([%d.-]+)[, ] *([%d.-]+)[, ] *([%d.-]+)$")
			if teleportee_name then
				teleportee = minetest.env:get_player_by_name(teleportee_name)
			end
			if teleportee and p.x and p.y and p.z then
				minetest.chat_send_player(name, "Teleporting "..teleportee_name.." to ("..p.x..", "..p.y..", "..p.z..")")
				teleportee:setpos(p)
				return
			end
			
			local teleportee = nil
			local p = nil
			local teleportee_name = nil
			local target_name = nil
			teleportee_name, target_name = string.match(param, "^([^ ]+) +([^ ]+)$")
			if teleportee_name then
				teleportee = minetest.env:get_player_by_name(teleportee_name)
			end
			if target_name then
				local target = minetest.env:get_player_by_name(target_name)
				if target then
					p = target:getpos()
				end
			end
			if teleportee and p then
				p = find_free_position_near(p)
				minetest.chat_send_player(name, "Teleporting "..teleportee_name.." to "..target_name.." at ("..p.x..", "..p.y..", "..p.z..")")
				teleportee:setpos(p)
				return
			end
		end

		minetest.chat_send_player(name, "Invalid parameters (\""..param.."\") or player not found (see /help teleport)")
		return
	end,
})

minetest.register_chatcommand("set", {
	params = "[-n] <name> <value> | <name>",
	description = "set or read server configuration setting",
	privs = {server=true},
	func = function(name, param)
		local arg, setname, setvalue = string.match(param, "(-[n]) ([^ ]+) (.+)")
		if arg and arg == "n" and setname and setvalue then
			minetest.setting_set(setname, setvalue)
			minetest.chat_send_player(name, setname.." = "..setvalue)
			return
		end
		local setname, setvalue = string.match(param, "([^ ]+) (.+)")
		if setname and setvalue then
			if not minetest.setting_get(setname) then
				minetest.chat_send_player(name, "Failed. Use '/set -n <name> <value>' to create a new setting.")
				return
			end
			minetest.setting_set(setname, setvalue)
			minetest.chat_send_player(name, setname.." = "..setvalue)
			return
		end
		local setname = string.match(param, "([^ ]+)")
		if setname then
			local setvalue = minetest.setting_get(setname)
			if not setvalue then
				setvalue = "<not set>"
			end
			minetest.chat_send_player(name, setname.." = "..setvalue)
			return
		end
		minetest.chat_send_player(name, "Invalid parameters (see /help set)")
	end,
})