#!/usr/bin/env bash
set -euo pipefail

# .claude-plugin/marketplace.json is apm's compiled Claude marketplace output (see
# apm.yml's marketplace.outputs.claude). GitHub Copilot CLI's manifest lookup accepts
# that same file at .claude-plugin/marketplace.json directly, but also has a legacy
# convention path at .github/plugin/marketplace.json (see
# plugins/kyberforge/docs/research/docs/github-copilot-plugins/marketplace.md) -- and
# CONTEXT.md documents that path as a mirror of the Claude output, not a separate apm
# output profile (apm only ships "claude" and "codex" mappers; codex writes a
# differently-shaped file to .agents/plugins/marketplace.json, not this path). This
# script keeps that legacy mirror byte-identical to .claude-plugin/marketplace.json
# instead of letting it silently drift (see issue #90 comment thread).

# Hard error, not a `|| pwd` fallback. Every path this script touches hangs off
# REPO_ROOT, and both of its exits-0 paths are "the files agree" or "neither file
# exists" -- so a REPO_ROOT pointing somewhere that is not this repo reports "no
# drift" over a tree it never looked at. Run `--check` from an empty directory
# outside any worktree and the fallback made that the literal outcome: rev-parse
# failed, REPO_ROOT became $PWD, neither file was there, exit 0. Refusing to guess
# is the only answer that cannot be silently wrong; the `-f "$DST"` branch below
# covers a genuinely stale mirror, which is a different condition.
if ! REPO_ROOT="$(git rev-parse --show-toplevel 2>/dev/null)" || [[ -z "$REPO_ROOT" ]]; then
  echo "Error: not inside a git worktree -- cannot locate the repository root, and guessing \$PWD would let --check report \"no drift\" over a tree it never inspected. Run this from within the repository." >&2
  exit 1
fi
SRC="$REPO_ROOT/.claude-plugin/marketplace.json"
DST="$REPO_ROOT/.github/plugin/marketplace.json"

usage() {
  echo "Usage: $0 [--check]" >&2
  exit 1
}

CHECK=0
if [[ "${1:-}" == "--check" ]]; then
  CHECK=1
  shift
fi
[[ $# -eq 0 ]] || usage

if [[ ! -f "$SRC" ]]; then
  # A missing source with a surviving mirror is drift, not absence: the mirror
  # can only be stale (nothing is left for it to be byte-identical to), which is
  # precisely the silent divergence this script exists to prevent. Exiting 0
  # here would report "no drift" over a mirror of a file that no longer exists.
  # (An unresolvable REPO_ROOT is handled above and is a hard error; this branch
  # is only about a source file that is genuinely gone from a real worktree.)
  # scripts/sync-plugin-content.sh --check --all already errors on the same
  # condition ("requires .../marketplace.json"); this matches it.
  # Neither file present stays a genuine no-op: nothing to mirror, nothing stale.
  if [[ "$CHECK" -eq 1 && -f "$DST" ]]; then
    echo "DRIFT $DST: mirror exists but .claude-plugin/marketplace.json does not" >&2
    echo "Fix: restore .claude-plugin/marketplace.json (apm's compiled Claude marketplace output), or delete $DST" >&2
    exit 1
  fi
  exit 0
fi

if [[ "$CHECK" -eq 1 ]]; then
  if [[ ! -f "$DST" ]] || ! diff -q "$SRC" "$DST" >/dev/null 2>&1; then
    echo "DRIFT $DST: out of sync with .claude-plugin/marketplace.json" >&2
    echo "Fix: bash scripts/sync-marketplace-mirror.sh" >&2
    exit 1
  fi
  exit 0
fi

mkdir -p "$(dirname "$DST")"
cp "$SRC" "$DST"