getting nvim to automacally set the tmux session based on current working dir (and also setting keymap for opening an alacritty session from nvim that sets the tmux session as well

[emilBeBri]

I so have an autocmd that sets the tmux session to send code to by:

`tx-

vim.cmd[[
function! SetTmuxSessionByDirectory()
    let current_dir = getcwd()

    " Extract the last part of the current directory
    let dir_name = fnamemodify(current_dir, ':t')

    " Create the session prefix using the last directory name
    let session_prefix = 'tx-' . dir_name

    " Check if the buffer already has a session set
    if exists('b:vimtux_session') && !empty(b:vimtux_session)
        return
    endif

    " Get list of tmux sessions
    let tmux_sessions = systemlist('tmux list-sessions -F "#{session_name}"')

    " Filter sessions that match the prefix
    let matching_sessions = filter(copy(tmux_sessions), {_, val -> val =~ '^' . session_prefix})

    " Set the session name based on matching sessions or default to session_prefix
    if empty(matching_sessions)
        let b:vimtux_session = session_prefix
    else
        " Sort sessions to find the one with the highest number
        call sort(matching_sessions)
        let highest_session = matching_sessions[-1]
        let b:vimtux_session = highest_session
    endif

    " Set the global vimtux variable
    let g:vimtux = { 'session': b:vimtux_session, 'window': '0', 'pane': '0' }

    " Silent message indicating the active session
    silent! echom "Active Session: " . g:vimtux['session']
endfunction

" Automatically set the tmux session on Vim startup, when opening a new file, switching buffers, and switching splits
autocmd VimEnter,BufReadPost,BufEnter,WinEnter * call SetTmuxSessionByDirectory()
]]

this works well with a keymap to:

{'<leader>ct', ":lua StartTmuxSession()<CR>", desc = 'open tmux term in PWD (named after pdw)'},

so this opens a new alacritty term with a tmux-session by the name of:

tx-<current_dir>

which is already set as the default session to send code to with the autocmd from above.

here are the function(s) called by the keymap:

-----------------------------------------
-- open tmux session by working dir, with incremental names #section

function GetUniqueTmuxSessionName(base_name)
    local session_name = base_name
    local counter = 1

    while true do
        local handle = io.popen('tmux has-session -t ' .. session_name .. ' 2>/dev/null && echo exists || echo not_exists')
        local result = handle:read("*a")
        handle:close()

        if result:find("not_exists") then
            break
        end

        counter = counter + 1
        session_name = string.format("%s-%02d", base_name, counter)
    end

    return session_name
end

-- key #uid-serrano1497
function StartTmuxSession()
    local cwd = vim.fn.getcwd()
    local dir = vim.fn.fnamemodify(cwd, ":t")
    local session_name = 'tx-' .. dir
    local unique_session_name = GetUniqueTmuxSessionName(session_name)
    local cmd = string.format("alacritty --working-directory %s -e tmux new-session -s %s", cwd, unique_session_name)
    print("Executing command: " .. cmd)
    vim.fn.jobstart(cmd, {detach = true})

    -- i3 commands to move the new terminal and adjust layout
    local i3_cmd_first_term = [[
        sleep 0.25s;  -- wait for the terminal to open
        i3-msg 'layout splith';
        sleep 0.1s;
        i3-msg 'move left';
        i3-msg 'resize shrink width 20 px or 20 ppt';
        i3-msg 'split toggle';
        i3-msg 'layout stacked';
        i3-msg 'focus right';
    ]]
    local i3_cmd_other_term = [[
        sleep 0.25s;  -- wait for the terminal to open
        i3-msg 'move left';
        i3-msg 'move left';
        i3-msg 'focus right';
    ]]

    -- Check if the base session name exists
    local handle = io.popen('tmux has-session -t ' .. session_name .. ' 2>/dev/null && echo exists || echo not_exists')
    local result = handle:read("*a")
    handle:close()

    local i3_cmd
    if result:find("not_exists") then
        i3_cmd = i3_cmd_first_term
    else
        i3_cmd = i3_cmd_other_term
    end

    os.execute(i3_cmd)
end

notice my working also does some rearranging by my windowmanager i3, but that can be removed or changed easliy.