. "$BST_LIB"
require s-nail s-nail/present

# Every invocation below passes -:/ (load no resource file at all) and points
# MAILRC at /dev/null, so what is asserted is s-nail's own behaviour and not
# whatever /etc/nail.rc happens to carry on this image. HOME is moved to the
# writable tmpfs because the rootfs is read-only at browser runtime and s-nail
# writes .mailrc-adjacent state next to it.
tmp=${TMPDIR:-/tmp}
MAILRC=/dev/null; export MAILRC
HOME=$tmp; export HOME

box=$tmp/bst-snail-rt.$$
multi=$tmp/bst-snail-multi.$$
empty=$tmp/bst-snail-empty.$$
rm -f "$box" "$multi" "$empty"

SUBJ='BRINTOS Round Trip 7'
BODY='BODY-hello-42'
HDR='X-Brintos-Arm: wasm32-hwjs'

# THE PIPELINE CASE, AND IT IS ALSO THE COMPOSE HALF OF THE ROUND TRIP. A
# recipient that names a file rather than an address makes s-nail append the
# composed message to that mbox instead of handing it to an MTA -- which is what
# lets this suite assert a real compose->store->read cycle with no SMTP peer
# anywhere. expandaddr=+file is what unlocks the file target; s-nail refuses it
# by default, and a port that quietly ignored the variable would deliver
# nothing here rather than deliver wrongly.
deliver() {  # deliver <subject> <body> <mbox> [extra-header]
  if [ -n "${4:-}" ]; then
    printf '%s\n' "$2" | s-nail -:/ -s "$1" -C "$4" -S expandaddr=+file -. "$3"
  else
    printf '%s\n' "$2" | s-nail -:/ -s "$1" -S expandaddr=+file -. "$3"
  fi
}

# An exit status is not evidence that a message was stored. A binary that did
# nothing at all and returned 0 satisfies `deliver` and every rc-only assertion
# built on it, so the delivery case requires the mbox to exist and be non-empty
# afterwards -- which is the difference between "s-nail ran" and "s-nail wrote".
deliver_ok() {
  deliver "$1" "$2" "$3" "${4:-}" || return $?
  [ -s "$3" ]
}

# Read a stored message back THROUGH S-NAIL rather than with cat: the point of
# the round trip is that s-nail's own reader parses what s-nail's own writer
# produced. `print 1` renders message 1 with its headers; -# is the batch mode
# that makes the reader consume a command stream on stdin.
readback() { printf 'print 1\nquit\n' | s-nail -:/ -# -f "$1"; }

check s-nail/deliver-file deliver_ok "$SUBJ" "$BODY" "$box" "$HDR"

# mbox format itself: a stored message opens with a "From " envelope line. A
# writer that emitted the headers but not the separator produces a file every
# reader mis-parses, and the header assertions below would still pass on it.
check_out s-nail/mbox-from   'From '  head -n 1 "$box"

rt=$(readback "$box" 2>&1)
check_out s-nail/rt-subject   "Subject: $SUBJ"  printf '%s\n' "$rt"
check_out s-nail/rt-body      "$BODY"           printf '%s\n' "$rt"
check_out s-nail/rt-customhdr "$HDR"            printf '%s\n' "$rt"
check_out s-nail/rt-useragent 'User-Agent: s-nail' printf '%s\n' "$rt"
check_out s-nail/rt-date      'Date: '          printf '%s\n' "$rt"

# A body of several lines, asserted line by line and in order -- a reader that
# folds or reorders the body would still satisfy a single-line body check.
printf 'l1-alpha\nl2-beta\nl3-gamma\n' | s-nail -:/ -s 'Multi' -S expandaddr=+file -. "$multi" >/dev/null 2>&1
mrt=$(readback "$multi" 2>&1)
check_out s-nail/multiline-1 'l1-alpha' printf '%s\n' "$mrt"
check_out s-nail/multiline-2 'l2-beta'  printf '%s\n' "$mrt"
check_out s-nail/multiline-3 'l3-gamma' printf '%s\n' "$mrt"
check_eq  s-nail/multiline-order 'l1-alpha l2-beta l3-gamma' \
  "$(printf '%s\n' "$mrt" | sed -n 's/^\(l[123]-[a-z]*\)$/\1/p' | tr '\n' ' ' | sed 's/ $//')"

# Appending a second message to an existing mbox -- the operation a script that
# logs mail performs on every run, and the one that goes wrong when a writer
# truncates instead of appends.
deliver 'Subj B' 'BODY-second' "$box" >/dev/null 2>&1
check_eq s-nail/append-count 2 "$(grep -c '^From ' "$box")"
check_out s-nail/summary-subjects 'Subj B' \
  sh -c 'printf "headers\nquit\n" | s-nail -:/ -# -f "$1"' sh "$box"

# The has-mail exit status, both directions. Scripts branch on this, so the
# false direction matters as much as the true one: a port that always returned 0
# would pass the first of these two and fail the second.
: > "$empty"
check_rc s-nail/has-mail 0 s-nail -:/ -e -f "$box"
check_rc s-nail/no-mail  1 s-nail -:/ -e -f "$empty"

# mailx(1) is the name an operator and a shell script reach for, and it is the
# reason this package is in the image at all -- the recipe registers s-nail as
# the mailx alternative, so assert the ALTERNATIVE actually resolved rather than
# trusting the recipe line that asked for it.
if command -v mailx >/dev/null 2>&1; then
  check_out s-nail/mailx-alt 's-nail v14.9.24' mailx -:/ -Xversion -Xx
else
  bst_notok s-nail/mailx-alt 'mailx alternative not resolved on this image'
fi

# The evaluators, scored against values recorded from a native s-nail 14.9.24
# x86_64 control (2026-08-12) rather than from this arm. These are computed
# answers: a wasm32 build that started, echoed and delivered mail correctly can
# still get integer width or string indexing wrong, and nothing above would see
# it.
check_eq s-nail/version-major  14       "$(s-nail -:/ -X 'echo $version-major' -Xx 2>&1)"
check_eq s-nail/csop-length    14       "$(s-nail -:/ -X 'csop length brintos-wasm32' -Xx 2>&1)"
check_eq s-nail/csop-find      8        "$(s-nail -:/ -X 'csop find brintos-wasm32 wasm' -Xx 2>&1)"
check_eq s-nail/csop-substring 'wasm32' "$(s-nail -:/ -X 'csop substring brintos-wasm32 8' -Xx 2>&1)"
check_out s-nail/vexpr-add   '0x2A' s-nail -:/ -X 'vexpr + 40 2'      -Xx
check_out s-nail/vexpr-mul   '0x2A' s-nail -:/ -X 'vexpr * 6 7'       -Xx
check_out s-nail/vexpr-pbase '0xFF' s-nail -:/ -X 'vexpr pbase 16 255' -Xx

rm -f "$box" "$multi" "$empty"