#!/usr/bin/env bash
# ==============================================================================
# update.sh — Multi-Agent Mux (MAM) Orchestration Updater
# ==============================================================================
# Safely updates MAM skills, virtual environment, and docs to the latest version.
# Preserves user configuration (.env) and local metadata/jobs database (.mam).
# ==============================================================================
set -euo pipefail

TARGET_DIR=""
FORCE=0
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

# Parse arguments
while [[ $# -gt 0 ]]; do
  case "$1" in
    -y|--yes|--force)
      FORCE=1
      shift
      ;;
    *)
      TARGET_DIR="$1"
      shift
      ;;
  esac
done

if [ -z "$TARGET_DIR" ]; then
  if [ "$(basename "$SCRIPT_DIR")" = ".mam_deploy" ]; then
    TARGET_DIR="$(dirname "$SCRIPT_DIR")"
  else
    TARGET_DIR="$(pwd)"
  fi
else
  if [ "$(basename "$TARGET_DIR")" = ".mam_deploy" ]; then
    TARGET_DIR="$(dirname "$TARGET_DIR")"
  fi
  if [ ! -d "$TARGET_DIR" ]; then
    echo "❌ Error: Target directory '$TARGET_DIR' does not exist." >&2
    exit 1
  fi
  TARGET_DIR="$(cd "$TARGET_DIR" && pwd)"
fi

echo "===================================================================="
echo "⚡ Starting Multi-Agent Mux (MAM) Update"
echo "📂 Target Workspace: $TARGET_DIR"
echo "===================================================================="

cd "$TARGET_DIR"

# 1. Verification of existing install (B-2: dual resolution)
REMOVER=""
for cand in ".mam_deploy/remove.sh" "remove.sh"; do
  if [ -f "$cand" ]; then
    REMOVER="$cand"
    break
  fi
done

if [ -z "$REMOVER" ]; then
  echo "❌ Error: No MAM installation (remove.sh) found in '$TARGET_DIR'." >&2
  echo "   Please run install.sh first to set up the workspace." >&2
  exit 1
fi

# Request confirmation if not forced
if [ $FORCE -eq 0 ]; then
  echo "⚠️  WARNING: This will update MAM orchestration skills, virtual environment, "
  echo "   and docs to the latest version."
  echo "   (Your configuration, job history, and custom skills will be preserved)."
  if [ ! -t 0 ]; then
    echo "❌ Error: Non-interactive terminal detected. Please run with -y/--yes/--force." >&2
    exit 1
  fi
  if ! read -p "❓ Proceed with update? [y/N]: " -r response; then
    response="n"
  fi
  if [[ ! "$response" =~ ^[yY](es)?$ ]]; then
    echo "❌ Update cancelled by user."
    exit 0
  fi
fi

# 1.5 Pre-capture legacy ownership before remove.sh deletes the manifest (M-4)
MAM_LEGACY_ENV_OWNED=0
if [ -f ".mam/install_manifest.txt" ] && grep -Fqx ".env" ".mam/install_manifest.txt" 2>/dev/null; then
  MAM_LEGACY_ENV_OWNED=1
fi
export MAM_LEGACY_ENV_OWNED

# 2. Stage backups of user configurations and metadata to prevent deletion
echo "💾 Backing up configuration and database..."
HAS_ENV=0
ENV_BACKUP_SRC=""
ENV_BACKUP_TMP=""

if [ -f ".mam.env" ]; then
  HAS_ENV=1
  ENV_BACKUP_SRC=".mam.env"
  ENV_BACKUP_TMP=".mam.env.update-tmp"
  mv ".mam.env" "$ENV_BACKUP_TMP"
elif [ -f ".env" ]; then
  HAS_ENV=1
  ENV_BACKUP_SRC=".env"
  ENV_BACKUP_TMP=".env.update-tmp"
  mv ".env" "$ENV_BACKUP_TMP"
fi

HAS_MAM=0
if [ -d ".mam" ]; then
  HAS_MAM=1
  # Copy database and jobs to temporary backup outside of .mam.
  # We do NOT move the .mam folder away so that remove.sh can still read .mam/install_manifest.txt!
  mkdir -p .mam.update-tmp
  # Copy SQLite databases and session files
  for db in .mam/agent-sessions.*; do
    if [ -f "$db" ]; then
      cp -f "$db" .mam.update-tmp/
    fi
  done
  # Copy jobs history
  if [ -d ".mam/jobs" ] && [ "$(ls -A .mam/jobs 2>/dev/null)" ]; then
    mkdir -p .mam.update-tmp/jobs
    cp -rf .mam/jobs/* .mam.update-tmp/jobs/
  fi
  # Copy delegate logs
  if [ -d ".mam/delegate_job_logs" ] && [ "$(ls -A .mam/delegate_job_logs 2>/dev/null)" ]; then
    mkdir -p .mam.update-tmp/delegate_job_logs
    cp -rf .mam/delegate_job_logs/* .mam.update-tmp/delegate_job_logs/
  fi
  # Copy manifest so we have a backup
  if [ -f ".mam/install_manifest.txt" ]; then
    cp -f .mam/install_manifest.txt .mam.update-tmp/
  fi
  # C12: Copy MAM state files across update cycle
  for st in install_state asset_hashes.txt version.txt; do
    if [ -f ".mam/$st" ]; then
      cp -f ".mam/$st" .mam.update-tmp/
    fi
  done
  if [ -d ".mam/skill-backups" ]; then
    mkdir -p .mam.update-tmp/skill-backups
    cp -rf .mam/skill-backups/* .mam.update-tmp/skill-backups/ 2>/dev/null || true
  fi
fi

# Define trap to restore backup files on failure
restore_on_failure() {
  echo "❌ Update failed. Reverting configuration and database to previous state..."
  if [ $HAS_ENV -eq 1 ] && [ -n "$ENV_BACKUP_TMP" ] && [ -f "$ENV_BACKUP_TMP" ]; then
    mv -f "$ENV_BACKUP_TMP" "$ENV_BACKUP_SRC" 2>/dev/null || true
  fi
  if [ $HAS_MAM -eq 1 ] && [ -d ".mam.update-tmp" ]; then
    # Revert to old database/jobs backup by restoring .mam directory
    rm -rf .mam 2>/dev/null || true
    mkdir -p .mam
    cp -f .mam.update-tmp/agent-sessions.* .mam/ 2>/dev/null || true
    if [ -d ".mam.update-tmp/jobs" ]; then
      cp -rf .mam.update-tmp/jobs .mam/ 2>/dev/null || true
    fi
    if [ -d ".mam.update-tmp/delegate_job_logs" ]; then
      cp -rf .mam.update-tmp/delegate_job_logs .mam/ 2>/dev/null || true
    fi
    if [ -f ".mam.update-tmp/install_manifest.txt" ]; then
      cp -f .mam.update-tmp/install_manifest.txt .mam/ 2>/dev/null || true
    fi
    for st in install_state asset_hashes.txt version.txt; do
      if [ -f ".mam.update-tmp/$st" ]; then
        cp -f ".mam.update-tmp/$st" .mam/ 2>/dev/null || true
      fi
    done
    if [ -d ".mam.update-tmp/skill-backups" ]; then
      mkdir -p .mam/skill-backups
      cp -rf .mam.update-tmp/skill-backups/* .mam/skill-backups/ 2>/dev/null || true
    fi
    rm -rf .mam.update-tmp 2>/dev/null || true
  fi
}
trap restore_on_failure EXIT

# 3. Perform uninstallation of existing files
echo "🗑️  Removing existing installation..."
# remove.sh will run in manifest mode because .mam/install_manifest.txt is still present.
# It will delete .agents/, documents, scripts, .venv, and .mam folder.
bash "$REMOVER" --force "$TARGET_DIR"

# 4. Fetch and run the latest installer from Gitea
echo "📥 Fetching and running the latest installer..."
# Note: MAM_*_URL environment variables are automatically inherited by the child installer bash process.
INSTALLER_URL="${MAM_INSTALLER_URL:-https://git.godopu.com/tmpl/multi-agent-mux/raw/branch/main/deploy/install.sh}"
if command -v curl &>/dev/null; then
  curl -fsSL "$INSTALLER_URL" | bash -s -- "$TARGET_DIR"
elif command -v wget &>/dev/null; then
  wget -qO- "$INSTALLER_URL" | bash -s -- "$TARGET_DIR"
else
  echo "❌ Error: Neither 'curl' nor 'wget' is available to fetch the installer." >&2
  exit 1
fi

# Disable failure trap since installation succeeded
trap - EXIT

# 5. Restore backups of configuration and database
echo "🔄 Restoring configuration and database..."
if [ $HAS_ENV -eq 1 ] && [ -n "$ENV_BACKUP_TMP" ] && [ -f "$ENV_BACKUP_TMP" ]; then
  if [ "$MAM_LEGACY_ENV_OWNED" = "1" ] && [ "$ENV_BACKUP_SRC" = ".env" ] && [ ! -f ".mam.env" ]; then
    mv -f "$ENV_BACKUP_TMP" ".mam.env"
    chmod 0600 ".mam.env" 2>/dev/null || true
  else
    mv -f "$ENV_BACKUP_TMP" "$ENV_BACKUP_SRC"
  fi
fi

if [ $HAS_MAM -eq 1 ]; then
  if [ -d ".mam.update-tmp" ]; then
    # The installer created a new .mam directory with a new manifest.
    # We want to merge the old .mam database/jobs back while keeping the new manifest.
    for db in .mam.update-tmp/agent-sessions.*; do
      if [ -f "$db" ]; then
        cp -f "$db" .mam/
      fi
    done
    if [ -d ".mam.update-tmp/jobs" ] && [ "$(ls -A .mam.update-tmp/jobs 2>/dev/null)" ]; then
      mkdir -p .mam/jobs
      cp -rf .mam.update-tmp/jobs/* .mam/jobs/
    fi
    if [ -d ".mam.update-tmp/delegate_job_logs" ] && [ "$(ls -A .mam.update-tmp/delegate_job_logs 2>/dev/null)" ]; then
      mkdir -p .mam/delegate_job_logs
      cp -rf .mam.update-tmp/delegate_job_logs/* .mam/delegate_job_logs/
    fi
    for st in install_state asset_hashes.txt version.txt; do
      if [ -f ".mam.update-tmp/$st" ]; then
        cp -f ".mam.update-tmp/$st" .mam/
      fi
    done
    if [ -d ".mam.update-tmp/skill-backups" ]; then
      mkdir -p .mam/skill-backups
      cp -rf .mam.update-tmp/skill-backups/* .mam/skill-backups/ 2>/dev/null || true
    fi
    rm -rf ".mam.update-tmp"
  fi
fi

echo "===================================================================="
echo "🎉 Update complete!"
echo "===================================================================="