#!/usr/bin/env bash
# Generate a review package: commit list, stat summary, and the net
# diff with extended context, written to a file the reviewer reads in one
# call. Using the recorded per-task BASE (not HEAD~1) keeps multi-commit
# tasks intact.
#
# Usage: review-package BASE HEAD [OUTFILE]
# Default OUTFILE: <git-dir>/sdd/review-<base7>..<head7>.diff — unique per
# repo instance and per range, so concurrent sessions cannot collide and a
# re-review after fixes always gets a distinctly named fresh file.
set -euo pipefail

if [ $# -lt 2 ] || [ $# -gt 3 ]; then
  echo "usage: review-package BASE HEAD [OUTFILE]" >&2
  exit 2
fi

base=$1
head=$2

git rev-parse --verify --quiet "$base" >/dev/null || { echo "bad BASE: $base" >&2; exit 2; }
git rev-parse --verify --quiet "$head" >/dev/null || { echo "bad HEAD: $head" >&2; exit 2; }

if [ $# -eq 3 ]; then
  out=$3
else
  dir=$(git rev-parse --git-path sdd)
  mkdir -p "$dir"
  dir=$(cd "$dir" && pwd)
  out="$dir/review-$(git rev-parse --short "$base")..$(git rev-parse --short "$head").diff"
fi

{
  echo "# Review package: ${base}..${head}"
  echo
  echo "## Commits"
  git log --oneline "${base}..${head}"
  echo
  echo "## Files changed"
  git diff --stat "${base}..${head}"
  echo
  echo "## Diff"
  git diff -U10 "${base}..${head}"
} > "$out"

commits=$(git rev-list --count "${base}..${head}")
echo "wrote ${out}: ${commits} commit(s), $(wc -c < "$out" | tr -d ' ') bytes"