#!/usr/bin/env bash
# SessionStart digest: fetch remote, report incoming commits + open Forgejo
# issues/PRs. Emits a Claude hook JSON blob on stdout (additionalContext) so
# Claude can surface anything actionable at the top of the session.
# Always exits 0 and always prints valid JSON — must never block a session.

set -o pipefail
cd "$(dirname "$0")/.." 2>/dev/null || exit 0

digest=""
add() { digest+="$1"$'\n'; }

# --- Remote fetch + incoming/outgoing commit comparison ------------------
if git rev-parse --git-dir >/dev/null 2>&1; then
  git fetch --all --quiet 2>/dev/null
  upstream=$(git rev-parse --abbrev-ref --symbolic-full-name '@{u}' 2>/dev/null)
  if [ -n "$upstream" ]; then
    incoming=$(git log --oneline "HEAD..$upstream" 2>/dev/null)
    outgoing=$(git log --oneline "$upstream..HEAD" 2>/dev/null)
    if [ -n "$incoming" ]; then
      add "INCOMING commits on $upstream (you are behind — pull to get them):"
      while IFS= read -r l; do add "  $l"; done <<< "$incoming"
      # Flag incoming edits to Unity scene/prefab/asset files — risky to pull
      # while the Editor is open (it may overwrite them or hold a stale copy).
      scenefiles=$(git diff --name-only "HEAD..$upstream" 2>/dev/null | grep -Ei '\.(unity|prefab|asset|mat|controller)$')
      if [ -n "$scenefiles" ]; then
        add "  *** WARNING: incoming commits change Unity scene/asset files:"
        while IFS= read -r f; do add "      $f"; done <<< "$scenefiles"
        add "  *** CLOSE or save the Unity Editor before pulling to avoid clobbering scene state."
      fi
    else
      add "Up to date with $upstream (no incoming commits)."
    fi
    [ -n "$outgoing" ] && add "You have $(wc -l <<< "$outgoing") local commit(s) not yet pushed."
  fi
fi

# --- Forgejo open issues + PRs -------------------------------------------
remote_url=$(git remote get-url origin 2>/dev/null)
if [[ "$remote_url" =~ ^https?://([^/]+)/([^/]+)/([^/.]+) ]]; then
  host="${BASH_REMATCH[1]}"; owner="${BASH_REMATCH[2]}"; repo="${BASH_REMATCH[3]}"
  cred=$(grep -m1 "$host" "$HOME/.git-credentials" 2>/dev/null)
  tok=$(sed -E 's#https?://([^@]+)@.*#\1#' <<< "$cred")
  api="https://$host/api/v1/repos/$owner/$repo/issues"
  parse='import sys,json
try: d=json.load(sys.stdin)
except: sys.exit(0)
for i in d: print("  #%d %s (by %s)"%(i["number"],i["title"],i["user"]["login"]))'
  if [ -n "$tok" ]; then
    issues=$(curl -sf --max-time 8 -u "$tok" "$api?state=open&type=issues" 2>/dev/null | python3 -c "$parse" 2>/dev/null)
    prs=$(curl -sf --max-time 8 -u "$tok" "$api?state=open&type=pulls" 2>/dev/null | python3 -c "$parse" 2>/dev/null)
    if [ -n "$issues" ]; then add "OPEN ISSUES:"; add "$issues"; else add "No open issues."; fi
    if [ -n "$prs" ]; then add "OPEN PULL REQUESTS:"; add "$prs"; else add "No open PRs."; fi
  fi
fi

# --- Emit hook JSON ------------------------------------------------------
ctx="[Session start — repo/remote status]
$digest
If there are INCOMING commits or any open issues/PRs, briefly tell the user at the start of your first reply. If everything is up to date with no open items, do not mention this."

python3 - "$ctx" <<'PY'
import json,sys
print(json.dumps({"hookSpecificOutput":{"hookEventName":"SessionStart","additionalContext":sys.argv[1]},"suppressOutput":True}))
PY
exit 0