#!/usr/bin/env bash
# push-fork-branches.sh — Stage Round 3+ fork advances to origin.
#
# Per AGENTS.md "BRANCH AND SUBMODULE POLICY", pushing diverged
# fork branches requires operator review. This script prints the
# necessary commands so the operator can run them manually after
# review.
#
# Usage:
#   ./local/scripts/push-fork-branches.sh           # show diff + commands
#   ./local/scripts/push-fork-branches.sh --execute  # execute safe-by-default
#
# Default mode: NO-OP. The script only prints what SHOULD be pushed.
# The operator must hand-run the commands shown.
#
# Reasons for "do not auto-push":
# 1. Multiple forks diverged: 202 ahead (userutils), 448 ahead (syscall),
#    and small diverges (base 202 ahead, etc).
# 2. Pushing would clobber commits that origin has that we don't
#    (Phase 1.0 + Phase 2.0 will be lost).
# 3. Per AGENTS.md: "Agents MUST NOT create new branches. … no pushing
#    new branches." This script never creates branches — it only
#    fast-forwards existing submodule/<name> branches to commits that
#    have already been made inside the local forks.
#
# Strategy: for each fork with `N ahead`, use `git push --force-with-lease`
# against the tracked upstream ref (submodule/<name>). The force-with-lease
# ensures we don't clobber concurrent pushes we haven't seen.

# Note: do NOT use `set -e` here — some ahead/behind calculations
# legitimately return empty strings when fork and ref are equal, and
# the pipefail behavior interferes with the cd sub-shells. Keep this
# script tolerant of harmless failures so its output is diagnostic.

set -uo pipefail

ROOT="$(cd "$(dirname "$0")/../.." && pwd)"
cd "$ROOT"

FORKS=(base bootloader installer kernel libredox relibc syscall userutils)

echo "=== Red Bear fork-branch status vs origin (2026-07-12) ==="
echo ""
printf "%-12s  %-15s  %-10s  %-10s\n" "fork" "local" "ahead" "behind"
echo "----------  ---------------  ----------  ----------"

REVIEW_NEEDED=()
for fork in "${FORKS[@]}"; do
    cd "local/sources/$fork" || continue
    remote_sha=$(git ls-remote origin "refs/heads/submodule/$fork" 2>&1 | awk '{print $1}')
    local_sha=$(git rev-parse HEAD 2>&1)
    # Avoid the ambiguous `HEAD` syntax by using the commit SHA directly.
    # The fork's `HEAD` may also be ambiguous when the working tree has
    # a stale symlink that confuses git's revision parser.
    if [ -n "$local_sha" ] && [ -n "$remote_sha" ]; then
        ahead=$(git rev-list --count "$remote_sha..$local_sha" 2>/dev/null | head -1 || echo "?")
        # Reverse direction: count commits on remote not in local
        behind=$(git rev-list --count "$local_sha..$remote_sha" 2>/dev/null | head -1 || echo "?")
    else
        ahead="?"
        behind="?"
    fi
    printf "%-12s  %-15s  %-10s  %-10s\n" "$fork" "${local_sha:0:12}" "${ahead:-?}" "${behind:-?}"

    if [ "${behind:-0}" -eq 0 ] 2>/dev/null && [ "${ahead:-0}" -gt 0 ] 2>/dev/null; then
        REVIEW_NEEDED+=("$fork:$ahead")
    fi
    cd "$ROOT"
done

echo ""
echo "=== Push commands (review BEFORE running) ==="
echo ""
echo "# Each line: cd into the fork, push to origin's submodule/<fork> ref."
echo "# --force-with-lease prevents clobbering concurrent work we haven't seen."
echo ""

for fork in "${REVIEW_NEEDED[@]}"; do
    fname="${fork%:*}"
    cnt="${fork#*:}"
    echo "# $fname: $cnt commits ahead — review via:"
    echo "   cd local/sources/$fname && git log origin/submodule/$fname..HEAD --oneline"
    echo "   # Then push (REVIEW the diff first):"
    echo "   cd $ROOT/local/sources/$fname && git push --force-with-lease=refs/heads/submodule/$fname:\$(git ls-remote origin refs/heads/submodule/$fname | awk '{print \$1}') origin HEAD:refs/heads/submodule/$fname"
    echo ""
done

echo "=== Other forks ==="
echo ""
echo "libredox: dropped .cargo-ok + .cargo_vcs_info.json, tightened .gitignore."
echo "  → Push with:  cd local/sources/libredox && git push origin HEAD:refs/heads/submodule/libredox"
echo ""
echo "bootloader: 927 vs 77 file divergence (mark 'diverged' in fork-upstream-map.toml)."
echo "  → DO NOT auto-push. Phase 2.4+ work: upgrade-forks.sh bootloader manual run."
echo ""
echo "installer: 30 vs 22 file divergence (mark 'diverged')."
echo "  → DO NOT auto-push. Phase 2.4+ work."
echo ""
echo "kernel: branch 0.3.1 (local release branch, not submodule/kernel)."
echo "  → Kernel's branch naming is intentional. DO NOT push to submodule/kernel."
echo ""

if [ "${1:-}" = "--execute" ]; then
    echo ""
    echo "=== EXECUTING ==="
    echo "If you ran --execute, you are forcibly advancing submodule/\$fork refs."
    echo "Press Ctrl-C within 5 seconds to abort."
    sleep 5
    for fork in "${REVIEW_NEEDED[@]}"; do
        fname="${fork%:*}"
        cd "$ROOT/local/sources/$fname" || continue
        remote_sha=$(git ls-remote origin "refs/heads/submodule/$fname" 2>/dev/null | awk '{print $1}')
        if [ -n "$remote_sha" ]; then
            echo "Pushing $fname (force-with-lease=$remote_sha)..."
            if git push --force-with-lease="refs/heads/submodule/$fname:$remote_sha" \
                       origin "HEAD:refs/heads/submodule/$fname" 2>&1 | tail -3; then
                echo "  $fname: pushed OK"
            else
                echo "  $fname: PUSH FAILED — operator review required"
            fi
        fi
        cd "$ROOT"
    done
fi

echo ""
echo "=== To push libredox cleanup (no force-with-lease needed, fast-forward): ==="
echo "  cd local/sources/libredox && git push origin HEAD:refs/heads/submodule/libredox"