vimcat

#!/bin/sh
#! vi: set noautoindent :: Vi/ViM
#!/usr/bin/env vim
#! This is a shell script that executes itself as a vimscript to do its work
#!-
#! Copyright (c) 2008 Matthew J. Wozniski <mjw@drexel.edu>
#! Copyright (c) 2017 Devin Teske <dteske@FreeBSD.org>
#! All rights reserved.
#!
#! Redistribution and use in source and binary forms, with or without
#! modification, are permitted provided that the following conditions
#! are met:
#! 1. Redistributions of source code must retain the above copyright
#!    notice, this list of conditions and the following disclaimer.
#! 2. Redistributions in binary form must reproduce the above copyright
#!    notice, this list of conditions and the following disclaimer in the
#!    documentation and/or other materials provided with the distribution.
#!
#! THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
#! ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
#! IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
#! ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
#! FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
#! DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
#! OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
#! HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
#! LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
#! OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
#! SUCH DAMAGE.
#!
#! $FreeBSD$
#! $FrauBSD$
#!
#!########################################################## SH MAIN
: if 0
    : "Bourne shell code goes here, but you cannot use if-statements"

    case "$0" in
    /*) script="$0" ;;
     *) script="$PWD/$0"
    esac

    : ${UNAME_s:=$( uname -s )}
    export darwin=0
    case "$UNAME_s" in
    Darwin) darwin=1 ;;
    esac

    [ $# -lt 1 -o "$1" = "-" ] && {
        tmpfile=$( mktemp -t "${0##*/}.XXXXXXXX" )
        trap 'rm -f "$tmpfile"' EXIT
        eval 'cat > "$tmpfile" || exit'
        [ $# -gt 0 ] && shift 1 # -
        set -- "$tmpfile" "$@"
    }

    vim -e -X -R "$@" -c "source $script" -c "visual" \
        -c "bufdo call AnsiHighlight()" -c qa < /dev/tty | awk '
            NR == 1 { sub(/^[^"]*"[^"]*"[[:space:]]*/, "") }
            gsub(/\x1b\[[[:digit:]]+;1H/, "") { }
            !/^\x1b\[\?1l/
        '

    exit

    : "The remainder of this file is vimscript"
: endif
#!########################################################## VIM FUNCTIONS

:
: "Convert info for a highlight group to a string of ANSI color escapes"
:
function! s:GroupToAnsi(groupnum)
    if !exists("s:ansicache")
        let s:ansicache = {}
    endif

    let groupnum = a:groupnum
    if !groupnum
        let groupnum = hlID("Normal")
    endif

    if has_key(s:ansicache, groupnum)
        return s:ansicache[groupnum]
    endif

    let rv = synIDattr(groupnum, "reverse", s:type)
    if rv == "" || rv == -1
        let rv = 0
    endif

    let bd = synIDattr(groupnum, "bold", s:type)
    if bd == "" || bd == -1
        let bd = 0
    endif

    let fg = synIDattr(groupnum, "fg", s:type)
    let bg = synIDattr(groupnum, "bg", s:type)

    if rv
        let temp = bg
        let bg = fg
        let fg = temp
    endif

    if fg >= 8 && fg < 16
        let fg -= 8
        let bd = 1
    endif

    if fg == "" || fg == -1
        unlet fg
    endif

    if !exists("fg") && !groupnum == hlID("Normal")
        let fg = synIDattr(hlID("Normal"), "fg", s:type)
        if fg == "" || fg == -1
            unlet fg
        endif
    endif

    if bg == "" || bg == -1
        unlet bg
    endif

    if !exists("bg") && !groupnum == hlID("Normal")
        let bg = synIDattr(hlID("Normal"), "bg", s:type)
        if bg == "" || bg == -1
            unlet bg
        endif
    endif

    let retv = "\<Esc>[0"

    if bd
        let retv .= ";1"
    endif

    if exists("fg") && fg < 8
        let retv .= ";3" . fg
    elseif exists("fg")
        let retv .= ";38;5;" . fg
    endif

    if exists("bg") && bg < 8
        let retv .= ";4" . bg
    elseif exists("bg")
        let retv .= ";48;5;" . bg
    endif

    let retv .= "m"

    let s:ansicache[groupnum] = retv

    return retv
endfunction

function! AnsiHighlight()
    let retv = []

    for lnum in range(1, line("$"))
        let last = hlID("Normal")
        let output = s:GroupToAnsi(last) . "\<Esc>[K"

        : "Hopefully fix highlighting sync issues"
        exe "norm! " . lnum . "G$"

        let line = getline(lnum)

        for cnum in range(1, col("."))
            if synIDtrans(synID(lnum, cnum, 1)) != last
                let last = synIDtrans(synID(lnum, cnum, 1))
                let output .= s:GroupToAnsi(last)
            endif

            let output .= matchstr(line, '\%(\zs.\)\{'.cnum.'}')
        endfor

        let retv += ["\r" . output]
    endfor

    : "Reset the colors to default after displaying the file"
    let retv[-1] .= "\<Esc>[0m"

    if !$darwin
        echo ""
    endif

    return writefile([""] + retv, "/dev/stdout", "b")
endfunction

#!########################################################## VIM MAIN

set nocompatible
if &t_Co
    let s:type = "cterm"
else
    let s:type = "term"
endif

: "Prevent statusmsg on exit when reading stdin on Darwin"
if $darwin
    let ignored = system(":")
endif

#!##############################################################################
#! END
#!##############################################################################