HyperionOS/Src/Hyperion-bash/bin/lua

syscall.devctl(1,"sfgc",7)
print("HyperionOS Lua prompt.")
print("Call exit() to exit.")

local commandHistory = {}
local luaEnv=setmetatable({
    ["exit"] = setmetatable({}, {
        __tostring = function() return "Call exit() to exit." end,
        __call = function() syscall.exit() end,
    }),
    ["_echo"] = function(...)
        return ...
    end,
},{__index=_ENV})

local function getUserInput()
    syscall.devctl(1,"sfgc",1)
    printInline("lua> ")
    local curOffsetStr = syscall.devctl(1, "gpos")
    local curOffsetX = tonumber(curOffsetStr:sub(1, curOffsetStr:find(";")-1))
    local curOffsetY = tonumber(curOffsetStr:sub(curOffsetStr:find(";")+1))

    local input = ""
    local blinkState = false 
    local cursorPos = 1
    local history = 0

    while true do
        local key=syscall.read(0)
        if key then
            if key == "\19" then --TODO: REPLACE WITH LEFT ARROW
                if cursorPos > 1 then
                    cursorPos = cursorPos - 1
                end
            elseif key == "\20" then --TODO: REPLACE WITH RIGHT ARROW
                if cursorPos <= #input then
                    cursorPos = cursorPos + 1
                end
            elseif key == "\17" then --TODO: REPLACE WITH UP ARROW
                if history < #commandHistory then
                    syscall.devctl(1,"spos",curOffsetX,curOffsetY)
                    printInline((" "):rep(#input + 1))
                    history = history + 1
                    input = commandHistory[#commandHistory - history + 1]
                    cursorPos = #input + 1
                end
            elseif key == "\18" then --TODO: REPLACE WITH DOWN ARROW
                if history > 1 then
                    syscall.devctl(1,"spos",curOffsetX,curOffsetY)
                    printInline((" "):rep(#input + 1))
                    history = history - 1
                    input = commandHistory[#commandHistory - history + 1]
                    cursorPos = #input + 1
                elseif history == 1 then
                    syscall.devctl(1,"spos",curOffsetX,curOffsetY)
                    printInline((" "):rep(#input + 1))
                    history = 0
                    input = ""
                    cursorPos = 1
                end
            elseif key == "\b" then
                if cursorPos > 1 then
                    syscall.devctl(1,"spos",curOffsetX,curOffsetY)
                    printInline((" "):rep(#input + 1))
                    input = string.sub(input, 1, cursorPos-2)..string.sub(input, cursorPos)
                    cursorPos = cursorPos - 1
                end
            elseif key == "\n" then
                syscall.devctl(1,"spos",curOffsetX,curOffsetY)
                print(input.." ")
                return input
            else
                input = string.sub(input, 1, cursorPos-1)..key..string.sub(input, cursorPos)
                cursorPos = cursorPos + 1
            end
            local screenSizeStr = syscall.devctl(1, "size")
            local sizeX = tonumber(screenSizeStr:sub(1, screenSizeStr:find(";")-1))
            local sizeY = tonumber(screenSizeStr:sub(screenSizeStr:find(";")+1))
            local totalChars = sizeX * sizeY
            local eocCharNum = ((curOffsetY - 1) * sizeX) + curOffsetX + #input
            if eocCharNum >= totalChars then
                syscall.devctl(1,"spos",sizeX,sizeY)
                printInline(" ")
                curOffsetY = curOffsetY - 1
            end
        end
        syscall.devctl(1,"spos",curOffsetX,curOffsetY)
        printInline(string.sub(input, 1, cursorPos-1))
        if blinkState then
            syscall.devctl(1,"sfgc",16)
            syscall.devctl(1,"sbgc",1)
        end
        if cursorPos > #input then
            printInline(" ")
        else
            printInline(string.sub(input, cursorPos, cursorPos))
        end
        syscall.devctl(1,"sfgc",1)
        syscall.devctl(1,"sbgc",16)
        printInline(string.sub(input, cursorPos+1))
        if cursorPos <= #input then
            printInline(" ")
        end
        local curBlink = ((math.floor(syscall.getUptime() / 500) % 2) == 0)
        if curBlink ~= blinkState then
            blinkState = curBlink
        end
    end
end

local function runCode(code)
    local func, err = load(code, "@lua", "t", luaEnv)
    local isReturn = false
    if load("return "..code) then
        func, err = load("return _echo("..code.."\n)", "@lua", "t", luaEnv)
        isReturn = true
    end
    if not func then
        local errSL = string.sub(err, string.find(err, ":") + 1)
        syscall.devctl(1,"sfgc",2)
        printInline("@lua: Load error on line ")
        print(string.sub(errSL, 1, string.find(errSL, ":") - 1))
        syscall.devctl(1,"sfgc",1)
        print(string.sub(errSL, string.find(errSL, ":") + 1))
        return
    end

    local success, msg = xpcall(func, debug.traceback)
    if not success then
        local errSL = string.sub(msg, string.find(msg, ":") + 1)
        syscall.devctl(1,"sfgc",2)
        printInline("@lua: Runtime error on line ")
        print(string.sub(errSL, 1, string.find(errSL, ":") - 1))
        syscall.devctl(1,"sfgc",1)
        print(string.sub(errSL, string.find(errSL, ":") + 1))
    elseif isReturn then
        print(tostring(msg))
    end
end

while true do
    local code = getUserInput()
    if code ~= "" then
        if code ~= commandHistory[#commandHistory] then
            table.insert(commandHistory, code)
        end
        runCode(code)
    end
end