# Copyright © 2013, 2021 Nick Bowler
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.

AT_BANNER([Image format tests])

m4_divert_push([PREPARE_TESTS])dnl
# Read the header from a PAM image (from standard input) and set declared
# parameters in shell variables.  For example, if the PAM header specifies
# DEPTH 2, the shell variable pam_DEPTH will be set to 2.
#
# Returns a nonzero status if the header could not be parsed.
pam_read_header () {
  pam_save_IFS=$IFS
  pam_p7_seen=false pam_endhdr_seen=false

  while IFS= read a; do
    case $a in
    P7)
      $pam_p7_seen && break # duplicated header
      pam_p7_seen=true
      ;;
    ENDHDR)
      pam_endhdr_seen=true
      break
      ;;
    *)
      IFS=$pam_save_IFS read b c <<EOF
$a
EOF
        b=AS_TR_SH([$b])
        AS_VAR_SET([pam_$b], [$c])
      ;;
    esac
  done

  IFS=$pam_save_IFS
  $pam_p7_seen && $pam_endhdr_seen
}

pam_check_header () {
  for pam_arg
  do
    AS_UNSET([pam_$pam_arg])
  done

  pam_read_header || return

  for pam_arg
  do
    AS_VAR_SET_IF([pam_$pam_arg],
      [AS_VAR_COPY([pam_val], [pam_$pam_arg])],
      [AS_UNSET([pam_val])])
    AS_ECHO(["$pam_arg${pam_val+ = }${pam_val- unset}"])
  done
}
m4_divert_pop([PREPARE_TESTS])

AT_SETUP([Empty image])

AT_CHECK([lbximg -F pbm -dnf "$testdata/image-0x0" && cat out.000.pbm], [0],
[P1
0 0
])

AT_CLEANUP

AT_SETUP([PAM output format (no palette)])

# image-1x1 (no palette)
AT_CHECK([lbximg -F pam -dnf "$testdata/image-1x1"])
AT_CHECK([pam_check_header WIDTH HEIGHT DEPTH TUPLTYPE <out.000.pam], [0],
[WIDTH = 1
HEIGHT = 1
DEPTH = 1
TUPLTYPE = GRAYSCALE
])

AT_CLEANUP

AT_SETUP([PAM output format (no palette + transparency)])

# image-1x1 (no palette)
AT_CHECK([lbximg -F pam -dnf "$testdata/image-1x1-mt"])
AT_CHECK([pam_check_header WIDTH HEIGHT DEPTH TUPLTYPE <out.000.pam], [0],
[WIDTH = 1
HEIGHT = 1
DEPTH = 2
TUPLTYPE = GRAYSCALE_ALPHA
])

AT_CLEANUP

AT_SETUP([PAM output format (palette)])

# image-1x1 (no palette)
AT_CHECK([lbximg -F pam -df "$testdata/image-1x1" \
                 -p "$testdata/palette-ramp"])
AT_CHECK([pam_check_header WIDTH HEIGHT DEPTH TUPLTYPE <out.000.pam], [0],
[WIDTH = 1
HEIGHT = 1
DEPTH = 3
TUPLTYPE = RGB
])

AT_CLEANUP

AT_SETUP([PAM output format (palette + transparency)])

# image-1x1 (no palette)
AT_CHECK([lbximg -F pam -df "$testdata/image-1x1-mt" \
                 -p "$testdata/palette-ramp"])
AT_CHECK([pam_check_header WIDTH HEIGHT DEPTH TUPLTYPE <out.000.pam], [0],
[WIDTH = 1
HEIGHT = 1
DEPTH = 4
TUPLTYPE = RGB_ALPHA
])

AT_CLEANUP