#!/usr/bin/env bash
# host_sync.sh — keep the HOST working tree (~/legal-ai) in sync with origin/main.
#
# Why this exists: the writer (block_writer), the learning panels
# (style_lesson_panel), and the legal_mcp MCP tools run from the host tree — the
# Paperclip agents `claude -p` with cwd=/home/chaim/legal-ai, and the long-running
# pm2 services import legal_mcp from mcp-server/src. A merge to main + Coolify
# deploy only refreshes the CONTAINER (FastAPI endpoints); host-side code stays on
# whatever was last `git pull`ed. On 2026-06-28 the host was 16 commits behind, so a
# full day of learning-loop fixes sat dormant until a manual pull. This closes that
# gap (TaskMaster #160).
#
# Safety: fast-forward ONLY (never force, never lose local work). The host tree
# carries a perpetually-dirty .taskmaster/tasks/tasks.json (uncommitted by policy) —
# a clean ff leaves it untouched; if upstream ever touches the same file the ff
# fails and we log + bail rather than clobber it. Agent runs spawn fresh, so they
# pick up new code on the next wakeup with no restart; only the long-running pm2
# services that IMPORT app code are restarted, and only when their own files change.
set -uo pipefail

REPO=/home/chaim/legal-ai
LOG="$REPO/data/logs/host_sync.log"
mkdir -p "$REPO/data/logs"
log() { echo "$(date -u +%Y-%m-%dT%H:%M:%SZ) $*" >> "$LOG"; }

cd "$REPO" || { log "ERROR cd $REPO failed"; exit 1; }

# Only sync when on main (don't disturb a manual branch checkout).
branch=$(git rev-parse --abbrev-ref HEAD 2>/dev/null)
[ "$branch" = "main" ] || { log "skip: on branch '$branch', not main"; exit 0; }

git fetch origin main --quiet 2>>"$LOG" || { log "ERROR git fetch failed"; exit 1; }
local_head=$(git rev-parse HEAD)
remote_head=$(git rev-parse origin/main)
[ "$local_head" = "$remote_head" ] && exit 0   # up to date — quiet no-op

changed=$(git diff --name-only "$local_head" "$remote_head")
if ! git pull --ff-only origin main --quiet 2>>"$LOG"; then
    log "ERROR ff-only pull failed ($local_head → $remote_head) — manual intervention needed (likely local tasks.json vs upstream); NOT forcing"
    exit 1
fi
log "synced $local_head → $(git rev-parse --short HEAD) ($(echo "$changed" | wc -l) files)"

# Restart only the long-running services whose OWN code changed (precise, minimal
# churn). The agent path (writer/panels via fresh `claude -p`) needs no restart.
restart() { pm2 restart "$1" --update-env >/dev/null 2>>"$LOG" && log "restarted $1"; }
echo "$changed" | grep -q '^mcp-server/src/legal_mcp/chat_service/' && restart legal-chat-service
echo "$changed" | grep -qE '^mcp-server/src/legal_mcp/court_fetch_service/' && restart legal-court-fetch-service
echo "$changed" | grep -q '^scripts/reap_orphan_procs.py' && restart legal-reaper
exit 0