shell.lua

--[[
Usage:
When running wesnoth, type:

	:lua shell()

This will open the shell. Type any lua code you like in the shell. Variables will be stored in a shell-specific environment. The shell defines some additional functions:

	clear() :: clears the output area.
	close() :: closes the shell.
]]
local helper = wesnoth.require "lua/helper.lua"
local T = helper.set_wml_tag_metatable {}
local _ = wesnoth.textdomain "wesnoth"

shell = {meta={}}
setmetatable(shell, shell.meta)
shell.output = nil
shell.input = nil
shell.prompt = "> "
shell.print = function (...)
	local line = ""
	for i, v in ipairs(arg) do
		if line == "" then
			line = tostring(v)
		else
			line = line .. "\t" .. tostring(v)
		end
	end
	if shell.output == nil then
		shell.output = tostring(line)
	else
		shell.output = shell.output .. "\n" .. tostring(line)
	end
end
shell.env = {
	print = shell.print,
	clear = function()
		shell.output = nil
	end
}
setmetatable(shell.env, {__index = _G})
shell.history = {
	index = nil,
	next = function()
		i = shell.history.index
		if i == nil or i == 0 then return end
		i = i - 1
		shell.history.index = i
	end,
	prev = function()
		i = shell.history.index
		if i == nil and shell.history[0] == nil then
			shell.history[0] = shell.input
		end
		i = (i or 0) + 1
		if shell.history[i] == nil then return end
		shell.history.index = i
	end
}

local function postshow()
	shell.input = wesnoth.get_dialog_value "shell"
end

local function preshow()
	if shell.output ~= nil then
		wesnoth.set_dialog_value(shell.output, "shell_output")
	end
	if shell.history.index ~= nil then
		wesnoth.message("setting shell default value...")
		wesnoth.message(tostring(shell.history.index))
		wesnoth.message(tostring(shell.history[shell.history.index]))
		wesnoth.set_dialog_value(shell.history[shell.history.index], "shell")
	end
end

function shell:display()
	repeat
		local rval = wesnoth.show_dialog(shell.window, preshow, postshow)
		
		if rval == -1 then
			local input = shell.input
			shell.input = nil
			
			if input ~= "" then
				table.insert(shell.history, 1, input)
				shell.history[0] = nil
				shell.history.index = nil
			end
			shell.print(string.format("%s%s", shell.prompt, input))
			if input ~= "close()" and input ~= nil and input ~= "" then
				local func, err = loadstring(input, "stdin")
				if err then
					shell.print(err)
				else
					setfenv(func, shell.env)
					local success, rval = pcall(func)
					if rval ~= nil then
						shell.print(rval)
					end
				end
			end
		elseif rval == shell.rnext then
			shell.history.next()
		elseif rval == shell.rprev then
			shell.history.prev()
		end
	until input == "close()" or rval == -2
end
shell.meta.__call = shell.display

shell.rnext = 1
shell.rprev = 2
shell.rhist = 3
shell.window = {
	vertical_placement = "bottom",
	T.tooltip { id = "tooltip_large" },
	T.helptip { id = "tooltip_large" },
	T.grid{
		T.row{
			T.column{
				horizontal_alignment = "left",
				T.scroll_label{
					id = "shell_output",
				}
			}
		},
		T.row{
			T.column{
				horizontal_grow = true,
				T.text_box{
					id = "shell",
					--history = "shell_history",
				}
			}
		},
		T.row{
			T.column{
				T.grid{
					T.row{
						T.column{
							T.button{
								id = "shell_next",
								return_value = shell.rnext,
								label = _ "Next"
							}
						},
						T.column{
							T.button{
								id = "shell_prev",
								return_value = shell.rprev,
								label = _ "Previous"
							}
						},
						T.column{
							T.button{
								id = "shell_view_history",
								return_value = shell.rhist,
								label = _ "History"
							}
						}
					}
				}
			}
		},
		T.row{
			T.column{
				horizontal_alignment = "left",
				T.label{
					label = "Run lua or type close() to quit this shell.",
				}
			}
		}
	}
}