-- Multi-Line Text Editor for CC:Tweaked


local function clearScreen()
    term.clear()
    term.setCursorPos(1, 1)
end

local function printMenu()
    print("==== Simple Text Editor ====")
    print("Press F1 to save")
    print("Press F9 to quit")
    print("============================")
end

local function promptInput(prompt)
    write(prompt)
    return read()
end

local function drawText(lines, cursorLine, startLine)
    clearScreen()
    printMenu()
    for i = 1, 16 do
        if startLine + i <= #lines then
            term.setCursorPos(1, i + 3)
            write(lines[startLine + i])
        else
            term.setCursorPos(1, i + 3)
            write("")  -- Empty line
        end
    end
    term.setCursorPos(1, cursorLine + 3)
end

local function editFile(content)
    local lines = content or {}
    local cursorLine = #lines > 0 and #lines or 1
    local startLine = 1

    while true do
        drawText(lines, cursorLine, startLine)
        local event, key = os.pullEvent()

        if event == "key" then
            if key == keys.f1 then -- F1 to save
                return lines
            elseif key == keys.f9 then -- F9 to quit
                return nil
            elseif key == keys.up and cursorLine > 1 then
                cursorLine = cursorLine - 1
            elseif key == keys.down and cursorLine < #lines + 1 then
                cursorLine = cursorLine + 1
            elseif key == keys.enter then
                local newLine = ""
                table.insert(lines, cursorLine, newLine)
                cursorLine = cursorLine + 1
            elseif key == keys.backspace then
                if cursorLine > 1 then
                    lines[cursorLine - 1] = lines[cursorLine - 1]:sub(1, -2) -- Remove last character
                    if lines[cursorLine - 1] == "" then
                        table.remove(lines, cursorLine - 1) -- Remove the line if empty
                        cursorLine = cursorLine - 1
                    end
                end
            else
                local char = string.char(key)
                if char and #char == 1 then
                    if cursorLine <= #lines then
                        lines[cursorLine] = (lines[cursorLine] or "") .. char
                    else
                        lines[cursorLine] = char
                    end
                end
            end
        end

        -- Scroll if cursorLine exceeds the visible area
        if cursorLine > startLine + 13 then
            startLine = startLine + 1
        elseif cursorLine < startLine then
            startLine = startLine - 1
        end
    end
end

local function saveFile(filename, content)
    local file = fs.open(filename, "w")
    for _, line in ipairs(content) do
        file.writeLine(line)
    end
    file.close()
end

local function runEditor()
    while true do
        clearScreen()
        printMenu()
        local choice = promptInput("Choose an option (1: New File, 2: Open File, 3: Exit): ")

        if choice == "1" then
            local newContent = editFile(nil)
            if newContent then
                local filename = promptInput("Enter filename to save: ")
                saveFile(filename, newContent)
                print("File saved!")
                os.sleep(2)
            end
        elseif choice == "2" then
            local filename = promptInput("Enter filename to open: ")
            if fs.exists(filename) then
                local file = fs.open(filename, "r")
                local content = {}
                while true do
                    local line = file.readLine()
                    if not line then break end
                    table.insert(content, line)
                end
                file.close()
                local editedContent = editFile(content)
                if editedContent then
                    saveFile(filename, editedContent)
                    print("File updated!")
                    os.sleep(2)
                end
            else
                print("File not found!")
                os.sleep(2)
            end
        elseif choice == "3" then
            print("Exiting editor...")
            break
        else
            print("Invalid choice. Please select again.")
            os.sleep(2)
        end
    end
end

-- Run the text editor
runEditor()