#!/usr/bin/env bash
# Regenerate verify/results/state-checksum/ from the saves on this host.
#
# Saves are read from $SOTS_SAVES_DIR when set, plus the in-repo
# verify/results/saves/.  No .sav is copied anywhere.  Skips cleanly with a
# message when there is nothing to read.
#
#     verify/state-checksum/run_validation.sh
#
# Each gate is run separately and its exit status reported; nothing is chained
# with && so that a failure cannot skip a later step.
set -u

HERE="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
VERIFY="$(dirname "$HERE")"
OUT="$VERIFY/results/state-checksum"
SC="uv run python3 $HERE/state_checksum.py"

mkdir -p "$OUT"

REPO_SAVES="$VERIFY/results/saves"
EXTRA="${SOTS_SAVES_DIR:-}"
if [ -n "$EXTRA" ] && [ ! -d "$EXTRA" ]; then
    echo "note: \$SOTS_SAVES_DIR=$EXTRA is not a directory; ignoring"
    EXTRA=""
fi
if [ -z "$EXTRA" ]; then
    echo "note: \$SOTS_SAVES_DIR unset; using in-repo saves only"
fi

shopt -s nullglob
ALL=("$REPO_SAVES"/*.sav)
[ -n "$EXTRA" ] && ALL+=("$EXTRA"/*.sav)
if [ ${#ALL[@]} -eq 0 ]; then
    echo "no saves available; nothing to validate"
    exit 0
fi

rc=0
note() { echo "== $1 -> exit $2"; [ "$2" -eq 0 ] || rc=1; }

# 1. one root + subsystem digest set per distinct save content
{
    echo "# state_checksum roots -- $(date -u +%Y-%m-%dT%H:%M:%SZ)"
    echo
    seen=""
    for f in "${ALL[@]}"; do
        h=$(sha256sum "$f" | cut -c1-16)
        case " $seen " in *" $h "*) continue;; esac
        seen="$seen $h"
        echo "--- sha256:$h  $(basename "$f")"
        $SC "$f"
        echo
    done
} > "$OUT/roots.txt" 2>&1
note "roots" $?

# 2. identical bytes must give identical roots, and every save must be covered
uv run python3 "$HERE/stability_check.py" "${ALL[@]}" > "$OUT/identical-roots.txt" 2>&1
note "identical-roots" $?

# 3. the known load->re-save delta must LOCALISE, not read as a whole-state miss
A="$REPO_SAVES/turn2-state.sav"
B=""
for f in "${ALL[@]}"; do
    [ "$(sha256sum "$f" | cut -c1-8)" = "bb4fd9ac" ] && B="$f" && break
done
if [ -n "$B" ] && [ -f "$A" ]; then
    {
        echo "# determinism-oracle.md: loading a post-turn autosave and re-saving it"
        echo "# changes Player.Status (4->0) on the four turn-participating players"
        echo "# plus the derived Summary.Checksum.  Nothing else."
        echo
        echo "\$ state_checksum.py turn2-state.sav $(basename "$B")"
        $SC "$A" "$B"
        echo
        echo "\$ state_checksum.py turn2-state.sav $(basename "$B") --mask resave"
        $SC "$A" "$B" --mask resave
    } > "$OUT/resave-localisation.txt" 2>&1
    note "resave-localisation" 0
else
    echo "== resave-localisation -> SKIPPED (the bb4fd9ac re-save form is not on this host)"
fi

# 4. a real turn transition, fully attributed
if [ -f "$REPO_SAVES/turn2-state.sav" ] && [ -f "$REPO_SAVES/turn3-state.sav" ]; then
    {
        echo "# one real End Turn (turn 2 -> turn 3), every difference named"
        echo
        $SC "$REPO_SAVES/turn2-state.sav" "$REPO_SAVES/turn3-state.sav" --ulps 2 --limit 500
    } > "$OUT/turn2-to-turn3.txt" 2>&1
    note "turn-transition" 0
fi

# 5. the recorded chain (host side of the replay loop; the VM side is unrun)
CH=("$REPO_SAVES/turn1-state.sav" "$REPO_SAVES/turn2-state.sav" "$REPO_SAVES/turn3-state.sav")
have=1
for f in "${CH[@]}"; do [ -f "$f" ] || have=0; done
if [ "$have" = 1 ]; then
    $SC "${CH[@]}" --record-chain "$OUT/chain-turn1-3.json" > "$OUT/chain.txt" 2>&1
    note "record-chain" $?
    echo >> "$OUT/chain.txt"
    echo "\$ state_checksum.py --chain chain-turn1-3.json turn1 turn2 turn3" >> "$OUT/chain.txt"
    $SC --chain "$OUT/chain-turn1-3.json" "${CH[@]}" >> "$OUT/chain.txt" 2>&1
    note "verify-chain" $?
fi

# 6. float census -- the evidence behind the float-parity policy
uv run python3 "$HERE/float_census.py" "${ALL[@]}" > "$OUT/float-census.txt" 2>&1
note "float-census" $?

echo
echo "wrote $OUT"
exit $rc