#!/bin/sh -
#
# gif2anim [options] image_anim.gif...
#
# This script uses the ImageMagick 'convert' program to take a gif animation
# (normally ending in '_anim.gif' and NOT just '.gif') and converts it into a
# collection of X Pixmap files (or GIFs) as well as a "animation sequence
# file" which lists all settings needed to re-build the original GIF
# animation.
#
# The animation file uses the string "BASENAME" to represent the basenames for
# the individual frame images that it loads when re-creating the original GIF
# animation.  This allows you to specify a different set of images without
# changling any other settings.
#
# The resulting animation file can be used to re-build the animation either
# using the IM options contained (ignoring comments), or by giving the file to
# the "anim2gif" script which will also do the basename filename substitutions
# specified.
#
# OPTIONS
#      -d             1 For debugging
#                       It also outputs to the terminal.
#      -c             1 coalesce animation before parsing
#      -t             1 Add time synchronization comment before each frame
#      -l             1 just list the anim file to stdout, no images
#      -v             1 Be verbose in animation conversions
#      -n             1 no images, just create the '.anim' file
#      -g             1 use an GIF suffix for frame images (default)
#      -x             1 use an XPM suffix for frame images
#                       None support 
#      -s suffix      use this suffix for the frame images
#      -i initframe   number of the first frame image (def=1)
#      -b framename   basename for the individual frames
#      -o file.anim   output to this .anim file (- for stdout)
#
# NOTE: This script reqires both the ImageMagick 'convert' program and
# 'identify' programs to extract the images and information needed.
#
####
#
# WARNING: Input arguments are NOT tested for correctness.
# This script represents a security risk if used ONLINE.
# I accept no responsiblity for misuse. Use at own risk.
#
# Anthony Thyssen    25 April 1996    <anthony@cit.griffith.edu.au>
#
# 1 November 2005  Expanded with options for basename handling.
#
# Hiroshi Kamifuji   2022-02-03 
#    Ported UNIX-like sh to PowerShell.
#    Changed the method of specifying run-time arguments.
#
#


Param(
    [String]$in,
    [Int]$d = 0,
    [Int]$c = 0,
    [Int]$t = 0,
    [Int]$l = 0,
    [Int]$v = 0,
    [Int]$n = 0,
    [String]$s = "",
    [Int]$g = 0,
    [Int]$x = 0,
    [Int]$i = 0,
    [String]$b = "",
    [String]$o ="" 
    )

if ( $in -eq "" ) {
    Write-Host "Usage : gif2anim [-c 1] [-t 1] [-l 1] [-v 1] [-n 1] 
                                         [-s 1] [-g 1] [-x 1] [-i 1] [-b 1] [-o 1] in "
    Exit
}


$sfx="gif"           # Default output suffix of images to produce
$init=1              # the count for the first frame in sequence
$fmt="%03d"          # The format for frame count
$frames="true"       # output frame images by defult
$basename=""         # use this name for the individual frame images
$animfile=""         # no default animfile to output to.
$all_gifs=""         # forcefully convert any ".gif" file
$coalesce=""         # coalesce flag (off)
$VERBOSE= ""         # be verbose (off)
$time_sync=0         # add time sync comments (off)
$awk="awk"
$dbg = 0

$basename, $insfx = $in.Split(".")

if ( $c -gt 0 ) {
    $coalesce="-coalesce"  # coalesce animation (on)
}

if ( $t -gt 0 ) {
	$time_sync = 1     # add time sync comments (on)
}

if ( $l -gt 0 ) {
    $frames=               # List anim file to standard output, no images
    $animfile="-"
}

if ( $v -gt 0 ) {
    $VERBOSE="true"        # Be verbose
}

if ( $n -gt 0 ) {
	$frames=""         # don't output any individual frames
}

if ( $s ) {
    $sfx = $s              # output frame images with this suffix
}
elseif ( $g -gt 0 ) {
    $sfx = "gif"           # output frame images as GIF's (default)
}
elseif ( $x -gt 0 ) {
    $sfx = "xpm"           # output frame images as XPM's
    Write-Host "Not supported then exit."
    Exit
}

if ( $i -gt 0 ) {
    $init=$i               # the count for the first frame in sequence
}

if ( $b ) {
    $basename=$b           # use this basename for frames
}

if ( $o ) {
    $animfile=$o           # output .anim file here
}

if ( $d ) {
    $dbg = 1
}


# echo "input : $in"
# echo "coalesce : $coalesce"
# echo "time_sync : $time_sync"
# echo "frames : $frames"
# echo "animfile : $animfile"
# echo "VERBOSE : $VERBOSE"
# echo "frames : $frames"
# echo "sfx : $sfx"
# echo "init : $init"
# echo "basename : $basename"
# echo "animfile : $animfile"


$im6 = (gcm montage).Definition 2> -null
$im7 = (gcm magick).Definition 2> -null

# echo "im6 : $im6"
# echo "im7 : $im7"

if ( $im7 ) {
    $method = 1
    $magick = "magick"
}
elseif ( $im6  ) {
    $method =2 
    $magick = ""
}
else {
    echo "ImageMagick cannot be found and cannot be executed."
    Exit
}


# echo "magick : $magick"
# echo "method : $method"

switch ( $method ) {
    # Execute by ImageMagick7.x
    1 { 
          $Inf = magick convert "$in" $coalesce -verbose info:-
      }

    # Execute by ImageMagick6.x
    2 { 
          $Inf = convert "$in" $coalesce -verbose info:-
      }

}

$anim_output = (pwd).Path + "\$basename" + ".anim"
# echo "anim_output : $anim_output"

# $enc_utf8_with_bom    = new-object System.Text.UTF8Encoding $true
$enc_utf8_without_bom = new-object System.Text.UTF8Encoding $false
$file = New-Object System.IO.StreamWriter($anim_output, $false, $enc_utf8_without_bom )

# $file = New-Object System.IO.StreamWriter($anim_output, $false, [System.Text.Encoding]::GetEncoding("UTF-8"))

$loop = 0
$canvas_set = 0


#      BEGIN { print "#";
#              print "# Animation Sequence File \"'"$i"'\"";
#              print "# using a BASENAME of     \"'"$name"'\"";
#              print "# Extracted on    '"$date"'";
#              print "#";
#              frame='"$init"'
#              last_offset="+0+0";
#              time_sync='"$time_sync"';
#              time=0;
#            }
if ( $dbg ) { Write-Host "#" }
$file.WriteLine( "#" )

if ( $dbg ) { Write-Host "# Animation Sequence File `"$in`"" }
$file.WriteLine( "# Animation Sequence File `"$in`"" )

$name, $wk = $in.Split(".")
if ( $dbg ) { Write-Host "# using a BASENAME of     `"$name`"" }
$file.WriteLine( "# using a BASENAME of     `"$name`"" )

# $dt = date
$dt = (Get-Date).ToString("yyyy-MM-dd HH:mm:ss")
if ( $dbg ) { Write-Host "# Extracted on    $dt" }
$file.WriteLine( "# Extracted on    $dt" )

if ( $dbg ){ Write-Host "#" }
$file.WriteLine( "#" )

$frame = $init
$last_offset = "+0+0"
# $time_sync='"$time_sync"';
$time = 0
$wkk1 = ""

foreach ($ln in $Inf) {

    $lnd = $ln.Split(" ")
    for ($i=0; $i -lt $lnd.Length; $i++) {
	if ( $lnd[$i] ) {
	    break
	}
    }

#      /^  Iterations:/    { if ( ! loop ) {
#                              print "-loop " $NF;
#                              loop = 1;
#                          } }
    if ( $lnd[$i] -eq "Iterations:" ) {
	if ( ! $loop ) {
            $wkk = $lnd[$i + 1]
	    if ( $dbg ){ Write-Host "-loop $wkk" }
	    $file.WriteLine( "-loop $wkk" )

	    $loop = 1
        }
    }

#      /^  Delay:/         { delay = $NF; sub("x100$", "", delay); }
    if ( $lnd[$i] -eq "Delay:" ) {
	$delay, $wk = $lnd[$i + 1].Split("x")
    }

#      /^  Dispose:/       { dispose = $NF; }
    if ( $lnd[$i] -eq "Dispose:" ) {
        $dispose = $lnd[$i + 1]
    }

#      /^  Geometry:/      { size    = substr($NF,0,match($NF, /\+/ )-1 ); }
    if ( $lnd[$i] -eq "Geometry:" ) {
        $size, $wk = $lnd[$i + 1].Split("+")
    }

#      /^  Page geometry:/ { canvas  = substr($NF,0,match($NF, /\+/ )-1 );
#                            offset  = substr($NF,  match($NF, /\+/ ) );
#                          }
    if (( $lnd[$i] -eq "Page" ) -and ( $lnd[$i + 1] -eq "geometry:" )) {
        $canvas, $w1, $w2 = $lnd[$i + 2].Split("+")
        $offset = "+$w1+$w2"
    }

#      # End of Image Frame -- output collected image meta-data changes
#      /^  Tainted: / {
#          if ( ! canvas_set ) {
#              print "-page " canvas;
#              canvas_set = 1;
#          }
    if ( $lnd[$i] -eq "Tainted:" ) {
          if ( ! $canvas_set ) {
              if ( $dbg ) { Write-Host "-page $canvas" }
	      $file.WriteLine( "-page $canvas" )

              $canvas_set = 1;
          }

#          if ( time_sync )  printf "# TIME SYNC %d\n", time;
        if ( $time_sync ) {
            if ( $dbg ) { Write-Host "# TIME SYNC $time" }
	    $file.WriteLine( "# TIME SYNC $time" )

        }

#          if ( delay != last_delay ) {
#              print "-delay " delay;
#              last_delay = delay;
#          }
        if ( $delay -ne $last_delay ) {
            if ( $dbg ) { Write-Host "-delay $delay" } 
	    $file.WriteLine( "-delay $delay" ) 

            $last_delay = $delay
        }

#          time+=delay;
        $time += $delay

#          delay=0;   # no delay is given if it remains set to zero
        $delay = 0

#          if ( dispose != last_dispose ) {
#              print "-dispose " dispose;
#              last_dispose = dispose;
#          }
        if ( $dispose -ne $last_dispose ) {
            if ( $dbg ) { Write-Host "-dispose $dispose" }
	    $file.WriteLine( "-dispose $dispose" )

            $last_dispose = $dispose
        }

#          if ( offset != last_offset ) {
#              printf "%-16s ", "-page " offset;
#              last_offset = offset;
#          } else {
#              printf "%-16s ", "";
#          }
#          printf "BASENAME_'"$fmt.$sfx"'  # %s%s\n",
#                  frame++, size, offset;
        if ( $offset -ne $last_offset ) {
            $wkk1 = [String]::Format("-page {0,-6}    ", $offset)
#            Write-Host -NoNewline $wkk
            $last_offset = $offset
        }
        else {
            $wkk1 =  "                "
        }
	$wkk = "{0:D3}" -f $frame++
	if ( $dbg ) { Write-Host "$wkk1 BASENAME_$wkk.$sfx  # $size$offset" }
	$file.WriteLine( "$wkk1 BASENAME_$wkk.$sfx  # $size$offset" )


#        }

    }


}

#      END { if ( time_sync ) printf "# LOOP TIME %d\n", time; }
    if ( $time_sync ) {
        if ( $dbg ) { Write-Host "# LOOP TIME $time" }
	$file.WriteLine( "# LOOP TIME $time"  )

    }

$file.Close()


#  if [ "$frames" ]; then
#    convert "$i" $coalesce \
#            +repage -set delay 0 -set dispose none -loop 0 \
#            -scene $init +adjoin  "${name}_${fmt}.${sfx}"
#

switch ( $method ) {
    # Execute by ImageMagick7.x
    1 { 
        magick convert "$in" $coalesce `
            +repage -set delay 0 -set dispose none -loop 0 `
            -scene $init +adjoin  "${name}_${fmt}.${sfx}"
      }

    # Execute by ImageMagick6.x
    2 { 
        convert "$in" $coalesce `
            +repage -set delay 0 -set dispose none -loop 0 `
            -scene $init +adjoin  "${name}_${fmt}.${sfx}"
      }

}