Vim: Windows common keyboard shortcuts

" Windows common keyboard shortcuts and pasting behavior {{{

" Online posts:
" http://superuser.com/questions/321547/how-do-i-replace-paste-yanked-text-in-vim-without-yanking-the-deleted-lines
" http://pastebin.com/aBEsm5mV

" SOURCE: https://stackoverflow.com/questions/1533565/how-to-get-visually-selected-text-in-vimscript
"function! s:GetVisualSelection()
"    let [lnum1, col1] = getpos("'<")[1:2]
"    let [lnum2, col2] = getpos("'>")[1:2]
"    let lines = getline(lnum1, lnum2)
"    if strchars(lines) == 0 "len(lines) == 0
"        return ''
"    endif
"    let lines[-1] = lines[-1][: col2 - (&selection ==? 'inclusive' ? 1 : 2)]
"    let lines[0] = lines[0][col1 - 1:]
"    return join(lines, "\n")
"endfunction

" SOURCE: http://stackoverflow.com/questions/17838700/vimscript-get-visual-mode-selection-text-in-mapping
"function! s:GetVisualSelection()
"    let l=getline("'<")
"    let [line1,col1] = getpos("'<")[1:2]
"    let [line2,col2] = getpos("'>")[1:2]
"    return l[col1 - 1: col2 - 1]
"endfunction
"
" Not sure i need GetVisualSelection() but here is an example of usage
" If selection is one character
" if strchars(GetVisualSelection()) == 1
"    let cmd = 'P'

" Uncomment to enable debugging.
" Check debug output with :messages
"let s:debug_smart_cut = 1
"let s:debug_smart_copy = 1
"let s:debug_smart_paste = 1

function! SmartCut()
    execute 'normal! gv"+c'

    if visualmode() != "\<C-v>" " If not Visual-Block mode
        " Trim the last \r\n | \n | \r character in the '+' buffer
        " NOTE: This messes up Visual-Block pasting.
        let @+ = substitute(@+,'\(\r\?\n\|\r\)$','','g')
    endif

    if exists("s:debug_smart_cut") && s:debug_smart_cut
        echomsg "SmartCut '+' buffer: " . @+
    endif
endfunction

function! SmartCopy()
    execute 'normal! gv"+y'

    if visualmode() != "\<C-v>" " If not Visual-Block mode
        " Trim the last \r\n | \n | \r character in the '+' buffer
        " NOTE: This messes up Visual-Block pasting.
        let @+ = substitute(@+,'\(\r\?\n\|\r\)$','','g')
    endif

    if exists("s:debug_smart_copy") && s:debug_smart_copy
        echomsg "SmartCopy '+' buffer: " . @+
    endif
endfunction

" Delete to black hole register before pasting. This function is a smarter version of "_d"+P or "_dp to handle special cases better.
" SOURCE: http://stackoverflow.com/questions/12625722/vim-toggling-buffer-overwrite-behavior-when-deleting
function! SmartPaste()
    let mode = 'gv'

    let delete = '"_d'

    let reg = '"+'

    " See :help '> for more information. Hint: if you select some text and press ':' you will see :'<,'>
    " SOURCE: http://superuser.com/questions/723621/how-can-i-check-if-the-cursor-is-at-the-end-of-a-line
    " SOURCE: http://stackoverflow.com/questions/7262536/vim-count-lines-in-selected-range
    " SOURCE: https://git.zug.fr/config/vim/blob/master/init.vim
    " SOURCE: https://git.zug.fr/config/vim/blob/master/after/plugin/zzzmappings.vim
    let currentColumn = col(".")
    let currentLine = line(".")
    let lastVisibleLetterColumn = col("$") - 1
    let lastLineOfBuffer = line("$")
    let selectionEndLine = line("'>")
    let selectionEndLineLength = strchars(getline(selectionEndLine))
    let nextLineLength = strchars(getline(currentLine + 1))
    let selectionStartColumn = col("'<")
    let selectionEndColumn = col("'>")

    " If selection does not include or go beyond the last visible character of the line (by also selecting the invisible EOL character)
    if selectionEndColumn < selectionEndLineLength
        let cmd = 'P'

        if exists("s:debug_smart_paste") && s:debug_smart_paste
            echomsg "SmartPaste special case #1"
        endif

    " If attempting to paste on a blank last line
    elseif selectionEndLineLength == 0 && selectionEndLine == lastLineOfBuffer
        let cmd = 'P'

        if exists("s:debug_smart_paste") && s:debug_smart_paste
            echomsg "SmartPaste special case #2"
        endif

    " If selection ends after the last visible character of the line (by also selecting the invisible EOL character) and next line is not blank and not the last line
    elseif selectionEndColumn > selectionEndLineLength && nextLineLength > 0 && selectionEndLine != lastLineOfBuffer
        let cmd = 'P'

        if exists("s:debug_smart_paste") && s:debug_smart_paste
            echomsg "SmartPaste special case #3"
        endif

    " If selection ends after the last visible character of the line (by also selecting the invisible EOL character), or the line is visually selected (Shift + V), and next line is the last line
    elseif selectionEndColumn > selectionEndLineLength && selectionEndLine == lastLineOfBuffer
        " SOURCE:  http://vim.wikia.com/wiki/Quickly_adding_and_deleting_empty_lines

        " Fixes bug where if the last line is fully selected (Shift + V) and a paste occurs, that the paste appears to insert after the first character of the line above it because the delete operation [which occurs before the paste]
        " is causing the caret to go up a line, and then 'p' cmd causes the paste to occur after the caret, thereby pasting after the first letter of that line.
        " However this but does not occur if there's a blank line underneath the selected line, prior to deleting it, as the cursor goes down after the delete in that situation.
        "
        " Silent was added to suppress "W10: Warning: Changing a readonly file"
        " I got this message while trying to edit a file that was not actually readonly but rather only administrator-editable because it was located in a protected Windows folder.
        " Another way to fix this it is to do "set noro" (if &readonly), and reapply the readonly state after the append with "set ro" (if was readonly).
        " NOTE: "silent!" hides error messages and normal messages, and "silent" just hides normal messages.
        silent call append(selectionEndLine, "")

        let cmd = 'p'

        if exists("s:debug_smart_paste") && s:debug_smart_paste
            echomsg "SmartPaste special case #4"
        endif

    else
        let cmd = 'p'

        if exists("s:debug_smart_paste") && s:debug_smart_paste
            echomsg "SmartPaste default case"
        endif
    endif

    if exists("s:debug_smart_paste") && s:debug_smart_paste
        echomsg "SmartPaste debug info:"
        echomsg "    currentColumn: " . currentColumn
        echomsg "    currentLine: " . currentLine
        echomsg "    lastVisibleLetterColumn: " . lastVisibleLetterColumn
        echomsg "    lastLineOfBuffer: " . lastLineOfBuffer
        echomsg "    selectionEndLine: " . selectionEndLine
        echomsg "    selectionEndLineLength: " . selectionEndLineLength
        echomsg "    nextLineLength: " . nextLineLength
        echomsg "    selectionStartColumn: " . selectionStartColumn
        echomsg "    selectionEndColumn: " . selectionEndColumn
        echomsg "    cmd: " . cmd
        echo [getpos("'<")[1:2], getpos("'>")[1:2]]
        echo "visualmode(): " . visualmode()
        echo "mode(): " . mode()
    endif

    if visualmode() != "\<C-v>" " If not Visual-Block mode
        " Trim the last \r\n | \n | \r character in the '+' buffer
        " NOTE: This messes up Visual-Block pasting.
        let @+ = substitute(@+,'\(\r\?\n\|\r\)$','','g')
    endif

    try
        execute 'normal! ' . mode . delete . reg . cmd
    catch /E353:\ Nothing\ in\ register\ +/
    endtry

    " Move caret one position to right
    call cursor(0, col(".") + 1)
endfunction

" p or P delete to black hole register before pasting
" NOTE: <C-u> removes the '<,'> visual-selection from the command line. See :h c_CTRL-u
vnoremap <silent> p :<C-u>call SmartPaste()<CR>
vnoremap <silent> P :<C-u>call SmartPaste()<CR>

" MiddleMouse delete to black hole register before pasting
nnoremap <MiddleMouse> "+p " Changes default behavior from 'P' mode to 'p' mode for normal mode middle-mouse pasting
" NOTE: <C-u> removes the '<,'> visual-selection from the command line. See :h c_CTRL-u
vnoremap <silent> <MiddleMouse> :<C-u>call SmartPaste()<CR>
inoremap <MiddleMouse> <C-r><C-o>+

" Copy :messages to the clipboard.
" NOTE: This is a workaround for not being able to select-all + copy messages.
nnoremap <silent> <Leader>m :redir @*<BAR>silent execute ':messages'<BAR>redir END<CR>

" Disable weird multi-click things you can do with middle mouse button
" SOURCE: http://vim.wikia.com/wiki/Mouse_wheel_for_scroll_only_-_disable_middle_button_paste
noremap <2-MiddleMouse> <NOP>
inoremap <2-MiddleMouse> <NOP>
noremap <3-MiddleMouse> <NOP>
inoremap <3-MiddleMouse> <NOP>
noremap <4-MiddleMouse> <NOP>
inoremap <4-MiddleMouse> <NOP>

if os != "mac" " NOTE: MacVim provides Command+C|X|V|A|S and undo/redo support and also can Command+C|V to the command line by default.
    " SOURCE: https://opensource.apple.com/source/vim/vim-62.41.2/runtime/macmap.vim.auto.html
    " NOTE: Only copy and paste are possible in the command line from what i can tell.
    "       Their is no undo for text typed in the command line and you cannot paste text onto a selection of text to replace it.
    cnoremap <C-c> <C-y>
    cnoremap <C-v> <C-r>+

    " Cut, copy, and paste support for visual and insert mode (not for normal mode)
    " SOURCE: http://superuser.com/questions/10588/how-to-make-cut-copy-paste-in-gvim-on-ubuntu-work-with-ctrlx-ctrlc-ctrlv
    " NOTE: <C-u> removes the '<,'> visual-selection from the command line. See :h c_CTRL-u
    vnoremap <silent> <C-x> :<C-u>call SmartCut()<CR>
    vnoremap <silent> <C-c> :<C-u>call SmartCopy()<CR>
    vnoremap <silent> <C-v> :<C-u>call SmartPaste()<CR>
    inoremap <C-v> <C-r><C-o>+

    " Select-all support for normal, visual, and insert mode
    " http://vim.wikia.com/wiki/Using_standard_editor_shortcuts_in_Vim
    nnoremap <C-a> ggVG
    vnoremap <C-a> ggVG
    inoremap <C-a> <Esc>ggVG

    " Save file support for normal, visual, and insert mode
    " SOURCE: http://vim.wikia.com/wiki/Map_Ctrl-S_to_save_current_or_new_files
    " If the current buffer has never been saved, it will have no name,
    " call the file browser to save it, otherwise just save it.
    command -nargs=0 -bar Update if &modified |
                                \    if empty(bufname('%')) |
                                \        browse confirm write |
                                \    else |
                                \        confirm write |
                                \    endif |
                                \endif
    nnoremap <silent> <C-s> :update<CR>
    " NOTE: <C-u> removes the '<,'> visual-selection from the command line. See :h c_CTRL-u
    vnoremap <silent> <C-s> :<C-u>update<CR>V
    " NOTE: <C-o> executes a normal-mode command without leaving insert mode. See :help ins-special-special
    "inoremap <silent> <C-s> <C-o>:update<CR>
    "
    " <C-o> doesn't seem to work while also using the "Open the OmniCompletion menu as you type" code while the menu is visible.
    " Doing "call feedkeys("\<C-x>\<C-o>", "n")" to perform omni completion seems to be the issue.
    " However doing "call feedkeys("\<C-x>\<C-i>", "n")" to perform keywork completion seems to work without issue.
    "
    " Workaround will exit insert mode to execute the command and then enter insert mode.
    inoremap <silent> <C-s> <Esc>:update<CR>I

    " Undo and redo support for normal, visual, and insert mode
    " NOTE: <C-u> removes the '<,'> visual-selection from the command line. See :h c_CTRL-u
    nnoremap <C-z> <Esc>u
    vnoremap <C-z> :<C-u>uV
    inoremap <C-z> <Esc>uI

    nnoremap <C-y> <Esc><C-r>
    vnoremap <C-y> :<C-u><C-r>V
    inoremap <C-y> <Esc><C-r>I

    " Disable Vim normal-mode undo/redo keys.
    " NOTE: Disabled in part because <C-z> and <C-y> are mapped to undo/redo and also because visual-mode 'u' and 'U' manipulating the selected text case is useful, but also having 'u' as normal-mode undo is an accident waiting to happen.
    " SOURCE: https://stackoverflow.com/questions/57714401/vi-vim-remap-or-unmap-built-in-command-the-u-key-in-visual-mode
    nnoremap u <NOP>
    nnoremap <C-r> <NOP>

    function! Find()
        let wordUnderCursor = expand('<cword>')
        if strchars(wordUnderCursor) > 0
            execute 'promptfind ' . wordUnderCursor
        else
            execute 'promptfind'
        endif
    endfunction

    function! Replace()
        let wordUnderCursor = expand('<cword>')
        if strchars(wordUnderCursor) > 0
            execute 'promptrepl ' . wordUnderCursor
        else
            execute 'promptrepl'
        endif
    endfunction

    " Find and Find/Replace support for normal, visual, and insert mode
    nnoremap <silent> <C-f> :call Find()<CR>
    nnoremap <silent> <C-h> :call Replace()<CR>

    " NOTE: <C-u> removes the '<,'> visual-selection from the command line. See :h c_CTRL-u
    vnoremap <silent> <C-f> :<C-u>call Find()<CR>
    vnoremap <silent> <C-h> :<C-u>call Replace()<CR>

    " NOTE: <C-o> executes a normal-mode command without leaving insert mode. See :help ins-special-special
    inoremap <silent> <C-f> <C-o>:call Find()<CR>
    inoremap <silent> <C-h> <C-o>:call Replace()<CR>
endif

" }}} Windows common keyboard shortcuts and pasting behavior