" -*- vim -*-
" FILE: "C:\Documents and Settings\William Lee\vimfiles\plugin\DirDiff.vim" {{{
" LAST MODIFICATION: "Fri, 31 Oct 2003 07:51:17 Central Standard Time"
" HEADER MAINTAINED BY: N/A
" VERSION: 1.0.2
" (C) 2001-2003 by William Lee, <wl1012@yahoo.com>
" }}}


" PURPOSE: {{{
"   - Diffing a directory recursively and enable easy merging, copying and
"   deleting of files and directories.
"
" REQUIREMENTS:
"   - Make sure you have GNU diff in your path on Unix and Windows. I only
"     tested this on cygwin's version on Windows.  If you have a diff that
"     doesn't support -x or -I flag, do not set variable g:DirDiffExcludes and
"     g:DirDiffIgnore to "".  It should still work.
"   - On Windows, you need to have "xcopy", "copy", "del", and "rd" in your
"     path.
"   - On Unix, you need to have "rm" and "cp" in your path.
"
" USAGE:
"   Put this file in your ~/.vim/plugin
" 
"   Doing the following will generate a diff window.
"
"       :DirDiff <A:Src Directory> <B:Src Directory>
"   e.g.
"       :DirDiff ../something/dir1 /usr/bin/somethingelse/dir2
"
"   The following commands can be used inside the diff window:
"   'Enter','o' - Diff open: open the diff file(s) where your cursor is at
"   's' - Synchronize the current diff.  You can also select
"         a range (through visual) and press 's' to synchronize differences
"         across a range.
"
"         - There are 6 Options you can choose when you hit 's':
"           1. A -> B
"              Copy A to overwrite B
"              If A's file actually points to a directory, it'll copy it to B
"              recursively.
"           2. B -> A
"              Copy B to overwrite A
"              If B's file actually points to a directory, it'll copy it to A
"              recursively.
"           3. Always A
"              For the rest of the items that you've selected,
"              synchronize like (1).
"           4. Always B
"              For the rest of the items that you've selected,
"              synchronize like (2).
"           5. Skip
"              Skip this diff entry.
"           6. Cancel
"              Quit the loop and exit.
"
"   'u' - Diff update: update the diff window
"   'x' - Sets the exclude pattern, separated by ','
"   'i' - Sets the ignore pattern, separated by ','
"   'a' - Sets additional arguments for diff, eg. -w to ignore white space,
"         etc.
"   'q' - Quit DirDiff
"    
"   The following comamnds can be used in the Vim diff mode
"   \dg - Diff get: maps to :diffget<CR>
"   \dp - Diff put: maps to :diffput<CR>
"   \dj - Diff next: (think j for down) 
"   \dk - Diff previous: (think k for up)
"
" NOTES:
"   This script can copy and remove your files.  This can be powerful (or too
"   powerful) at times.  Please do not blame me if you use this and
"   disintegrate your hard work.  Be warned!
"
" CREDITS:
"
"   Please mail any comment/suggestion/patch to 
"
"   William Lee <wl1012@yahoo.com>
"
"   (c) 2001-2003. All Rights Reserved
"
" THANKS:
"
"   Robert Webb for his sorting function
"   Salman Halim, Yosuke Kimura, and others for their suggestions
"
" HISTORY:
"  1.0.2  - Fixed a small typo bug in the quit function.
"  1.0.1  - Ensure the path separator is correct when running in W2K
"  1.0  - Fixed a bug that flags errors if the user use the nowrapscan option.
"         Implements a quit function that exit the diff windows.
"  0.94 - Fixed a bug where the diff will give incorrect A and B file due to
"         similarity of directory names.  Allow you to modify the diff
"         argument.
"  0.93 - Opps, messed up the key mapping usage.
"  0.92 - Doesn't use n and p mappings since it confuses the search next key
"         mapping and causes some bugs.  Minor modification to change the
"         exclude and ignore pattern.
"  0.91 - Clean up delete routine.
"       - Added interactive mode.
"       - Added multiple entries of exclude and ignore pattern.  
"       - Custom configuration through global variables.
"       - Change exclude and ignore patterns on the fly.
"        
"  0.9  - Reorganization of the interface.  Much simplier dialog for
"         synchronization.  Support for range synchronization option (REALLY
"         powerful)
"       - Removed unnecessary key bindings.  All key bindings are local to
"         the diff window. (except for the \dg and \dp)
"
"  0.8  - Added syntax highlighting.
"       - Enter and double-click in buffer opens diff.
"       - Removed dependency on "sort"
"       - Removed usage of registry and marker
"       - Code cleanup and some bug fixes
"       - On Windows the diff command will use the -i flag instead
"       - Changed mappings for diff next (\dj) and diff previous (\dk)
"       - Added mappings for vim diff mode (\dg, \dp)
"
"  0.7  Initial Release
"
" }}}

" Public Interface:
command! -nargs=* -complete=dir DirDiff call <SID>DirDiff (<f-args>)
command! -nargs=0 DirDiffOpen call <SID>DirDiffOpen ()
command! -nargs=0 DirDiffNext call <SID>DirDiffNext ()
command! -nargs=0 DirDiffPrev call <SID>DirDiffPrev ()
command! -nargs=0 DirDiffUpdate call <SID>DirDiffUpdate ()
command! -nargs=0 DirDiffQuit call <SID>DirDiffQuit ()

if !hasmapto('<Plug>DirDiffGet')
  map <unique> <Leader>dg <Plug>DirDiffGet
endif
if !hasmapto('<Plug>DirDiffPut')
  map <unique> <Leader>dp <Plug>DirDiffPut
endif
if !hasmapto('<Plug>DirDiffNext')
  map <unique> <Leader>dj <Plug>DirDiffNext
endif
if !hasmapto('<Plug>DirDiffPrev')
  map <unique> <Leader>dk <Plug>DirDiffPrev
endif

" Global Maps:
map <unique> <script> <Plug>DirDiffGet    :diffget<CR>
map <unique> <script> <Plug>DirDiffPut    :diffput<CR>
map <unique> <script> <Plug>DirDiffNext    :call <SID>DirDiffNext()<CR>
map <unique> <script> <Plug>DirDiffPrev    :call <SID>DirDiffPrev()<CR>
map <unique> <script> <Plug>DirDiffQuit    :call <SID>DirDiffQuit()<CR>

" Default Variables.  You can override these in your global variables
" settings.
"
" For DirDiffExcludes and DirDiffIgnore, separate different patterns with a
" ',' (comma and no space!).
"
" eg. in your .vimrc file: let g:DirDiffExcludes = "CVS,*.class,*.o"
"                          let g:DirDiffIgnore = "Id:"
"                          " ignore white space in diff
"                          let g:DirDiffAddArgs = "-w" 
"
" You can set the pattern that diff excludes.  Defaults to the CVS directory
if !exists("g:DirDiffExcludes")
    let g:DirDiffExcludes = ""
endif
" This is the -I argument of the diff, ignore the lines of differences that
" matches the pattern
if !exists("g:DirDiffIgnore")
    let g:DirDiffIgnore = ""
endif
if !exists("g:DirDiffSort")
    let g:DirDiffSort = 1
endif
if !exists("g:DirDiffWindowSize")
    let g:DirDiffWindowSize = 14
endif
if !exists("g:DirDiffInteractive")
    let g:DirDiffInteractive = 0
endif
if !exists("g:DirDiffIgnoreCase")
    let g:DirDiffIgnoreCase = 0
endif
" Additional arguments
if !exists("g:DirDiffAddArgs")
    let g:DirDiffAddArgs = ""
endif

" Set some script specific variables:
"
let s:DirDiffFirstDiffLine = 6
let s:DirDiffALine = 1
let s:DirDiffBLine = 2

" -- Variables used in various utilities
if has("unix")
    let s:DirDiffCopyCmd = "cp"
    let s:DirDiffCopyFlags = ""
    let s:DirDiffCopyDirCmd = "cp"
    let s:DirDiffCopyDirFlags = "-rf"
    let s:DirDiffCopyInteractiveFlag = "-i"

    let s:DirDiffDeleteCmd = "rm"
    let s:DirDiffDeleteFlags = ""
    let s:DirDiffDeleteInteractiveFlag = "-i"

    let s:DirDiffDeleteDirCmd = "rm"
    let s:DirDiffDeleteDirFlags = "-rf"

    let s:sep = "/"
elseif has("win32")
    let s:DirDiffCopyCmd = "copy"
    let s:DirDiffCopyFlags = ""
    let s:DirDiffCopyDirCmd = "xcopy"
    let s:DirDiffCopyDirFlags = "/e /i /q"
    let s:DirDiffCopyInteractiveFlag = "/-y"

    let s:DirDiffDeleteCmd = "del"
    let s:DirDiffDeleteFlags = "/s /q"
    let s:DirDiffDeleteInteractiveFlag = "/p"
    " Windows is somewhat stupid since "del" can only remove the files, not
    " the directory.  The command "rd" would remove files recursively, but it
    " doesn't really work on a file (!).  where is the deltree command???
     
    let s:DirDiffDeleteDirCmd = "rd"
    " rd is by default prompting, we need to handle this in a different way
    let s:DirDiffDeleteDirFlags = "/s"
    let s:DirDiffDeleteDirQuietFlag = "/q"

    let s:sep = "\\"
else
    " Platforms not supported
    let s:DirDiffCopyCmd = ""
    let s:DirDiffCopyFlags = ""
    let s:DirDiffDeleteCmd = ""
    let s:DirDiffDeleteFlags = ""
    let s:sep = ""
endif


function! <SID>DirDiff(srcA, srcB)
    " Setup
    let DirDiffAbsSrcA = fnamemodify(expand(a:srcA, ":p"), ":p")
    let DirDiffAbsSrcB = fnamemodify(expand(a:srcB, ":p"), ":p")

    " Remove the trailing \ or /
    let DirDiffAbsSrcA = substitute(DirDiffAbsSrcA, '\\$\|/$', '', '')
    let DirDiffAbsSrcB = substitute(DirDiffAbsSrcB, '\\$\|/$', '', '')

    let DiffBuffer = tempname()
    " We first write to that file
    " Constructs the command line
    let cmd = "!diff"
    let cmdarg = " -r --brief"

    " If variable is set, we ignore the case
    if (g:DirDiffIgnoreCase)
        let cmdarg = cmdarg." -i"
    endif
    if (g:DirDiffAddArgs != "")
        let cmdarg = cmdarg." ".g:DirDiffAddArgs." "
    endif
    if (g:DirDiffExcludes != "")
        let cmdarg = cmdarg.' -x"'.substitute(g:DirDiffExcludes, ',', '" -x"', 'g').'"'
    endif
    if (g:DirDiffIgnore != "")
        let cmdarg = cmdarg.' -I"'.substitute(g:DirDiffIgnore, ',', '" -I"', 'g').'"'
    endif
    " Prompt the user for additional arguments
"    let addarg = input("Additional diff args (current =". cmdarg. "): ")
    let addarg = ""
    let cmd = cmd.cmdarg." ".addarg." \"".DirDiffAbsSrcA."\" \"".DirDiffAbsSrcB."\""
    let cmd = cmd." > \"".DiffBuffer."\""

    echo "Diffing directories, it may take a while..."
    let error = <SID>DirDiffExec(cmd, 0)
    if (error == 0)
        echo "There is no diff here."
        return
    endif
    silent exe "edit ".DiffBuffer
    echo "Defining [A] and [B] ... "
    " We then do a substitution on the directory path
    " We need to do substitution of the the LONGER string first, otherwise
    " it'll mix up the A and B directory
    if (strlen(DirDiffAbsSrcA) > strlen(DirDiffAbsSrcB))
	    silent! exe "%s/".<SID>EscapeDirForRegex(DirDiffAbsSrcA)."/[A]/"
	    silent! exe "%s/".<SID>EscapeDirForRegex(DirDiffAbsSrcB)."/[B]/"
    else
	    silent! exe "%s/".<SID>EscapeDirForRegex(DirDiffAbsSrcB)."/[B]/"
	    silent! exe "%s/".<SID>EscapeDirForRegex(DirDiffAbsSrcA)."/[A]/"
    endif
    " In windows, diff behaves somewhat weirdly, for the appened path it'll
    " use "/" instead of "\".  Convert this to \
    if (has("win32"))
        silent! %s/\//\\/g
    endif

    echo "Sorting entries ..."
    " We then sort the lines if the option is set
    if (g:DirDiffSort == 1)
        1,$call <SID>Sort("s:Strcmp")
    endif

    " Put in spacer in front of each line
    silent! %s/^/    /

    " We then put the file [A] and [B] on top of the diff lines
    call append(0, "[A]=". DirDiffAbsSrcA)
    call append(1, "[B]=". DirDiffAbsSrcB)
    call append(2, "Usage:   <Enter>/'o'=open,'s'=sync,'\\dj'=next,'\\dk'=prev, 'q'=quit")
    call append(3, "Options: 'u'=update,'x'=set excludes,'i'=set ignore,'a'=set args" )
    call append(4, "Diff Args:" . cmdarg)
    call append(5, "")
    " go to the beginning of the file
    0
    setlocal nomodified
    setlocal nomodifiable
    setlocal buftype=nowrite
    setlocal bufhidden=delete
    setlocal nowrap

    " Set up local key bindings
    " 'n' actually messes with the search next pattern, I think using \dj and
    " \dk is enough.  Otherwise, use j,k, and enter.
"    nnoremap <buffer> n :call <SID>DirDiffNext()<CR>
"    nnoremap <buffer> p :call <SID>DirDiffPrev()<CR>
    nnoremap <buffer> s :. call <SID>DirDiffSync()<CR>
    vnoremap <buffer> s :call <SID>DirDiffSync()<CR>
    nnoremap <buffer> u :call <SID>DirDiffUpdate()<CR>
    nnoremap <buffer> x :call <SID>ChangeExcludes()<CR>
    nnoremap <buffer> a :call <SID>ChangeArguments()<CR>
    nnoremap <buffer> i :call <SID>ChangeIgnore()<CR>
    nnoremap <buffer> q :call <SID>DirDiffQuit()<CR>

    nnoremap <buffer> o    :call <SID>DirDiffOpen()<CR>
    nnoremap <buffer> <CR>  :call <SID>DirDiffOpen()<CR>  
    nnoremap <buffer> <2-Leftmouse> :call <SID>DirDiffOpen()<CR>
    call <SID>SetupSyntax()

    " Open the first diff
    call <SID>DirDiffNext()
endfunction

" Set up syntax highlighing for the diff window
function! <SID>SetupSyntax()
  if has("syntax") && exists("g:syntax_on") 
      "&& !has("syntax_items")
    syn match DirDiffSrcA               "\[A\]"
    syn match DirDiffSrcB               "\[B\]"
    syn match DirDiffUsage              "^Usage.*"
    syn match DirDiffOptions            "^Options.*"
    syn match DirDiffFiles              "Files"
    syn match DirDiffOnly               "Only in"
    syn match DirDiffSelected           "^==>.*" contains=DirDiffSrcA,DirDiffSrcB

    hi def link DirDiffSrcA               Directory
    hi def link DirDiffSrcB               Type
    hi def link DirDiffUsage              Special
    hi def link DirDiffOptions            Special
    hi def link DirDiffFiles              String
    hi def link DirDiffOnly               PreProc
    hi def link DirDiffSelected           DiffChange
  endif
endfunction

" You should call this within the diff window
function! <SID>DirDiffUpdate()
    let dirA = <SID>GetBaseDir("A")
    let dirB = <SID>GetBaseDir("B")
    call <SID>DirDiff(dirA, dirB)
endfun

" Quit the DirDiff mode
function! <SID>DirDiffQuit()
    let in = confirm ("Are you sure you want to quit DirDiff?", "&Yes\n&No", 2)
    if (in == 1)
        call <SID>CloseDiffWindows()
        bd!
    endif
endfun

" Returns an escaped version of the path for regex uses
function! <SID>EscapeDirForRegex(path)
    " This list is probably not complete, modify later
    return escape(a:path, "/\\[]$^")
endfunction

" Close the opened diff comparison windows if they exist
function! <SID>CloseDiffWindows()
    if (<SID>AreDiffWinsOpened())
        wincmd k
        " Ask the user to save if buffer is modified
        call <SID>AskIfModified()
        bd!
        " User may just have one window opened, we may not need to close
        " the second diff window
        if (&diff)
            call <SID>AskIfModified()
            bd!
        endif
    endif
endfunction


function! <SID>DirDiffOpen()
    " First dehighlight the last marked
    call <SID>DeHighlightLine()

    " Mark the current location of the line
    "mark n
    let b:currentDiff = line(".")

    " We first parse back the [A] and [B] directories from the top of the line
    let dirA = <SID>GetBaseDir("A")
    let dirB = <SID>GetBaseDir("B")

    call <SID>CloseDiffWindows()

    let line = getline(".")
    " Parse the line and see whether it's a "Only in" or "Files Differ"
    call <SID>HighlightLine()
    let fileA = <SID>GetFileNameFromLine("A", line)
    let fileB = <SID>GetFileNameFromLine("B", line)
    if <SID>IsOnly(line)
        " We open the file
        let fileSrc = <SID>ParseOnlySrc(line)
        if (fileSrc == "A")
            let fileToOpen = fileA
        elseif (fileSrc == "B")
            let fileToOpen = fileB
        endif
        split
        wincmd k
        silent exec "edit ".fileToOpen
        " Fool the window saying that this is diff
        diffthis
        wincmd j
        " Resize the window
        exe("resize " . g:DirDiffWindowSize)
        exe (b:currentDiff)
    elseif <SID>IsDiffer(line)
        "Open the diff windows
        split
        wincmd k
        silent exec "edit ".fileB
        silent exec "vert diffsplit ".fileA
        " Go back to the diff window
        wincmd j
        " Resize the window
        exe("resize " . g:DirDiffWindowSize)
        exe (b:currentDiff)
        " Center the line
        exe ("normal z.")
    else
        echo "There is no diff here!"
    endif
endfunction

" Ask the user to save if the buffer is modified
"
function! <SID>AskIfModified()
    if (&modified)
        let input = confirm("File " . expand("%:p") . " has been modified.", "&Save\nCa&ncel", 1)
        if (input == 1)
            w!
        endif
    endif
endfunction

function! <SID>HighlightLine()
    let savedLine = line(".")
    exe (b:currentDiff)
    setlocal modifiable
    let line = getline(".")
    if (match(line, "^    ") == 0)
        s/^    /==> /
    endif
    setlocal nomodifiable
    setlocal nomodified
    exe (savedLine)
    redraw
endfunction

function! <SID>DeHighlightLine()
    let savedLine = line(".")
    exe (b:currentDiff)
    let line = getline(".")
    setlocal modifiable
    if (match(line, "^==> ") == 0)
        s/^==> /    /
    endif
    setlocal nomodifiable
    setlocal nomodified
    exe (savedLine)
    redraw
endfunction

" Returns the directory for buffer "A" or "B".  You need to be in the diff
" buffer though.
function! <SID>GetBaseDir(diffName)
    let currLine = line(".")
    if (a:diffName == "A")
        let baseLine = s:DirDiffALine
    else
        let baseLine = s:DirDiffBLine
    endif
    let regex = '\['.a:diffName.'\]=\(.*\)'
    let line = getline(baseLine)
    let rtn = substitute(line, regex , '\1', '')
    return rtn
endfunction

function! <SID>DirDiffNext()
    " If the current window is a diff, go down one
    if (&diff == 1)
        wincmd j
    endif
    " if the current line is <= 6, (within the header range), we go to the
    " first diff line open it
    if (line(".") < s:DirDiffFirstDiffLine)
        exe (s:DirDiffFirstDiffLine)
        let b:currentDiff = line(".")
    endif
    silent! exe (b:currentDiff + 1)
    call <SID>DirDiffOpen()
endfunction

function! <SID>DirDiffPrev()
    " If the current window is a diff, go down one
    if (&diff == 1)
        wincmd j
    endif
    silent! exe (b:currentDiff - 1)
    call <SID>DirDiffOpen()
endfunction

" For each line, we can perform a recursive copy or delete to sync up the
" difference. Returns non-zero if the operation is NOT successful, returns 0
" if everything is fine.
"
function! <SID>DirDiffSyncHelper(AB, line)
    let fileA = <SID>GetFileNameFromLine("A", a:line)
    let fileB = <SID>GetFileNameFromLine("B", a:line)
"    echo "Helper line is ". a:line. " fileA " . fileA . " fileB " . fileB
    if <SID>IsOnly(a:line)
        " If a:AB is "A" and the ParseOnlySrc returns "A", that means we need to
        " copy
        let fileSrc = <SID>ParseOnlySrc(a:line)
        let operation = ""
        if (a:AB == "A" && fileSrc == "A")
            let operation = "Copy"
            " Use A, and A has source, thus copy the file from A to B
            let fileFrom = fileA
            let fileTo = fileB
        elseif (a:AB == "A" && fileSrc == "B")
            let operation = "Delete"
            " Use A, but B has source, thus delete the file from B
            let fileFrom = fileB
            let fileTo = fileA
        elseif (a:AB == "B" && fileSrc == "A")
            let operation = "Delete"
            " Use B, but the source file is A, thus removing A
            let fileFrom = fileA
            let fileTo = fileB
        elseif (a:AB == "B" && fileSrc == "B")
            " Use B, and B has the source file, thus copy B to A
            let operation = "Copy"
            let fileFrom = fileB
            let fileTo = fileA
        endif
    elseif <SID>IsDiffer(a:line)
        " Copy no matter what
        let operation = "Copy"
        if (a:AB == "A")
            let fileFrom = fileA
            let fileTo = fileB
        elseif (a:AB == "B")
            let fileFrom = fileB
            let fileTo = fileA
        endif
    else 
        echo "There is no diff here!"
        " Error
        return 1
    endif
    if (operation == "Copy")
        let rtnCode = <SID>Copy(fileFrom, fileTo)
    elseif (operation == "Delete")
        let rtnCode = <SID>Delete(fileFrom)
    endif
    return rtnCode
endfunction

" Synchronize the range
function! <SID>DirDiffSync() range
    let answer = 1
    let silence = 0
    let syncMaster = "A"
    let currLine = a:firstline
    let lastLine = a:lastline
    let syncCount = 0

    while ((currLine <= lastLine))
        " Update the highlight
        call <SID>DeHighlightLine()
        let b:currentDiff = currLine
        call <SID>HighlightLine()
        let line = getline(currLine)
        if (!silence)
            let answer = confirm(substitute(line, "^....", '', ''). "\nSynchronization option:" , "&A -> B\n&B -> A\nA&lways A\nAl&ways B\n&Skip\nCa&ncel", 6)
            if (answer == 1 || answer == 3)
                let syncMaster = "A"
            endif
            if (answer == 2 || answer == 4)
                let syncMaster = "B"
            endif
            if (answer == 3 || answer == 4)
                let silence = 1
            endif
            if (answer == 5)
                let currLine = currLine + 1
                continue
            endif
            if (answer == 6)
                break
            endif
        endif

"        call <SID>DeHighlightLine()
        let rtnCode = <SID>DirDiffSyncHelper(syncMaster, line)
        if (rtnCode == 0)
            " Successful
            let syncCount = syncCount + 1
            " Assume that the line is synchronized, we delete the entry
            setlocal modifiable
            exe (currLine.",".currLine." delete")
            setlocal nomodifiable
            setlocal nomodified
            let lastLine = lastLine - 1
        else
            " Failed!
            let currLine = currLine + 1
        endif
    endwhile
    echo syncCount . " diff item(s) synchronized."
endfunction

" Return file "A" or "B" depending on the line given.  If it's a Only line,
" either A or B does not exist, but the according value would be returned.
function! <SID>GetFileNameFromLine(AB, line)
    " Determine where the source of the copy is.
    let dirA = <SID>GetBaseDir("A")
    let dirB = <SID>GetBaseDir("B")

    let fileToProcess = ""

    if <SID>IsOnly(a:line)
        let fileToProcess = <SID>ParseOnlyFile(a:line)
    elseif <SID>IsDiffer(a:line)
        let regex = '^.*Files\s\[A\]\(.*\)\sand\s\[B\]\(.*\)\sdiffer.*$'
        let fileToProcess = substitute(a:line, regex, '\1', '')
    else
    endif

    "echo "line : " . a:line. "AB = " . a:AB . " File to Process " . fileToProcess
    if (a:AB == "A")
        return dirA . fileToProcess
    elseif (a:AB == "B")
        return dirB . fileToProcess
    else
        return ""
    endif
endfunction

"Returns the source (A or B) of the "Only" line
function! <SID>ParseOnlySrc(line)
    return substitute(a:line, '^.*Only in \[\(.\)\].*:.*', '\1', '')
endfunction

function! <SID>ParseOnlyFile(line)
    let regex = '^.*Only in \[.\]\(.*\): \(.*\)'
    let root = substitute(a:line, regex , '\1', '')
    let file = root . s:sep . substitute(a:line, regex , '\2', '')
    return file
endfunction

function! <SID>Copy(fileFromOrig, fileToOrig)
    let fileFrom = substitute(a:fileFromOrig, '/', s:sep, 'g')
    let fileTo = substitute(a:fileToOrig, '/', s:sep, 'g')
    echo "Copy from " . fileFrom . " to " . fileTo
    if (s:DirDiffCopyCmd == "")
        echo "Copy not supported on this platform"
        return 1
    endif

    " Constructs the copy command
    let copycmd = "!".s:DirDiffCopyCmd." ".s:DirDiffCopyFlags
    " Append the interactive flag
    if (g:DirDiffInteractive)
        let copycmd = copycmd . " " . s:DirDiffCopyInteractiveFlag
    endif
    let copycmd = copycmd . " \"".fileFrom."\" \"".fileTo."\""

    " Constructs the copy directory command
    let copydircmd = "!".s:DirDiffCopyDirCmd." ".s:DirDiffCopyDirFlags
    " Append the interactive flag
    if (g:DirDiffInteractive)
        let copydircmd = copydircmd . " " . s:DirDiffCopyInteractiveFlag
    endif
    let copydircmd = copydircmd . " \"".fileFrom."\" \"".fileTo."\""

    let error = 0
    if (isdirectory(fileFrom))
        let error = <SID>DirDiffExec(copydircmd, g:DirDiffInteractive)
    else
        let error = <SID>DirDiffExec(copycmd, g:DirDiffInteractive)
    endif
    if (error != 0)
        echo "Can't copy from " . fileFrom . " to " . fileTo
        return 1
    endif
    return 0
endfunction

" Woudld execute the command, either silent or not silent, by the
" interactive flag ([0|1]).  Returns the v:shell_error after
" executing the command.
function! <SID>DirDiffExec(cmd, interactive)
    let error = 0
    if (a:interactive)
        exe (a:cmd)
        let error = v:shell_error
    else
        silent exe (a:cmd)
        let error = v:shell_error
    endif
"    let d = input("DirDiffExec: " . a:cmd . " " . a:interactive . " returns " . v:shell_error)
    return error
endfunction

" Delete the file or directory.  Returns 0 if nothing goes wrong, error code
" otherwise.
function! <SID>Delete(fileFromOrig)
    let fileFrom = substitute(a:fileFromOrig, '/', s:sep, 'g')
    echo "Deleting from " . fileFrom
    if (s:DirDiffDeleteCmd == "")
        echo "Delete not supported on this platform"
        return 1
    endif

    let delcmd = ""

    if (isdirectory(fileFrom))
        let delcmd = "!".s:DirDiffDeleteDirCmd." ".s:DirDiffDeleteDirFlags
        if (g:DirDiffInteractive)
            " If running on Unix, and we're running in interactive mode, we
            " append the -i tag
            if (has("unix"))
                let delcmd = delcmd . " " . s:DirDiffDeleteInteractiveFlag
            endif
        else
            " If running on windows, and we're not running in interactive
            " mode, we append the quite flag to the "rd" command
            if (has("win32"))
                let delcmd = delcmd . " " . s:DirDiffDeleteDirQuietFlag
            endif
        endif
    else
        let delcmd = "!".s:DirDiffDeleteCmd." ".s:DirDiffDeleteFlags
        if (g:DirDiffInteractive)
            let delcmd = delcmd . " " . s:DirDiffDeleteInteractiveFlag
        endif
    endif

    let delcmd = delcmd ." \"".fileFrom."\""
    let error = <SID>DirDiffExec(delcmd, g:DirDiffInteractive)
    if (error != 0)
        echo "Can't delete " . fileFrom
    endif
    return error
endfunction

function! <SID>AreDiffWinsOpened()
    let currBuff = expand("%:p")
    let currLine = line(".")
    wincmd k
    let abovedBuff = expand("%:p")
    if (&diff)
        let abovedIsDiff = 1
    else
        let abovedIsDiff = 0
    endif
    " Go Back if the aboved buffer is not the same
    if (currBuff != abovedBuff)
        wincmd j
        " Go back to the same line
        exe (currLine)
        if (abovedIsDiff == 1)
            return 1
        else
            " Aboved is just a bogus buffer, not a diff buffer
            return 0
        endif
    else
        exe (currLine)
        return 0
    endif
endfunction

" The given line begins with the "Only in"
function! <SID>IsOnly(line)
    return (match(a:line, "^    Only in\\|^==> Only in") == 0)
endfunction

" The given line begins with the "Files"
function! <SID>IsDiffer(line)
    return (match(a:line, "^    Files\\|^==> Files") == 0)
endfunction

" Let you modify the Exclude patthern
function! <SID>ChangeExcludes()
    let g:DirDiffExcludes = input ("Exclude pattern (separate multiple patterns with ','): ", g:DirDiffExcludes)
    echo "\nPress update ('u') to refresh the diff."
endfunction

" Let you modify additional arguments for diff
function! <SID>ChangeArguments()
    let g:DirDiffAddArgs = input ("Additional diff args: ", g:DirDiffAddArgs)
    echo "\nPress update ('u') to refresh the diff."
endfunction

" Let you modify the Ignore patthern
function! <SID>ChangeIgnore()
    let g:DirDiffIgnore = input ("Ignore pattern (separate multiple patterns with ','): ", g:DirDiffIgnore)
    echo "\nPress update ('u') to refresh the diff."
endfunction

" Sorting functions from the Vim docs.  Use this instead of the sort binary.
"
" Function for use with Sort(), to compare two strings.
func! <SID>Strcmp(str1, str2)
  if (a:str1 < a:str2)
	return -1
  elseif (a:str1 > a:str2)
	return 1
  else
	return 0
  endif
endfunction

" Sort lines.  SortR() is called recursively.
func! <SID>SortR(start, end, cmp)
  if (a:start >= a:end)
	return
  endif
  let partition = a:start - 1
  let middle = partition
  let partStr = getline((a:start + a:end) / 2)
  let i = a:start
  while (i <= a:end)
	let str = getline(i)
	exec "let result = " . a:cmp . "(str, partStr)"
	if (result <= 0)
	    " Need to put it before the partition.  Swap lines i and partition.
	    let partition = partition + 1
	    if (result == 0)
		let middle = partition
	    endif
	    if (i != partition)
		let str2 = getline(partition)
		call setline(i, str2)
		call setline(partition, str)
	    endif
	endif
	let i = i + 1
  endwhile

  " Now we have a pointer to the "middle" element, as far as partitioning
  " goes, which could be anywhere before the partition.  Make sure it is at
  " the end of the partition.
  if (middle != partition)
	let str = getline(middle)
	let str2 = getline(partition)
	call setline(middle, str2)
	call setline(partition, str)
  endif
  call <SID>SortR(a:start, partition - 1, a:cmp)
  call <SID>SortR(partition + 1, a:end, a:cmp)
endfunc

" To Sort a range of lines, pass the range to Sort() along with the name of a
" function that will compare two lines.
func! <SID>Sort(cmp) range
  call <SID>SortR(a:firstline, a:lastline, a:cmp)
endfunc