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

server_url="${BOSS_SERVER_URL:-http://127.0.0.1:43210}"
session_file="${BOSS_SESSION_FILE:-.boss-session}"

usage() {
  cat <<'EOF'
Usage:
  boss_chat.sh sessions
  boss_chat.sh create [title]
  boss_chat.sh send "<message>" [session_id]
  boss_chat.sh status [session_id]

Environment:
  BOSS_SERVER_URL   Default: http://127.0.0.1:43210
  BOSS_SESSION_FILE Default: .boss-session
EOF
}

require_tools() {
  command -v curl >/dev/null 2>&1 || {
    echo "curl is required" >&2
    exit 1
  }
  command -v node >/dev/null 2>&1 || {
    echo "node is required" >&2
    exit 1
  }
}

request() {
  local method="$1"
  local path="$2"
  local body="${3:-}"

  if [[ -n "$body" ]]; then
    curl -fsS -X "$method" "$server_url$path" -H 'Content-Type: application/json' -d "$body"
  else
    curl -fsS -X "$method" "$server_url$path"
  fi
}

json_payload() {
  local key="$1"
  local value="$2"
  node -e 'const [key, value] = process.argv.slice(1); process.stdout.write(JSON.stringify({ [key]: value }));' "$key" "$value"
}

json_message_payload() {
  local value="$1"
  node -e 'const value = process.argv[1]; process.stdout.write(JSON.stringify({ content: value, channel: "cli" }));' "$value"
}

json_get() {
  local expr="$1"
  node -e "const fs = require('fs'); const data = JSON.parse(fs.readFileSync(0, 'utf8')); const result = (${expr}); if (result === undefined || result === null) process.exit(2); if (typeof result === 'string') process.stdout.write(result); else process.stdout.write(JSON.stringify(result, null, 2));"
}

save_session_id() {
  printf '%s' "$1" > "$session_file"
}

load_session_id() {
  if [[ -f "$session_file" ]]; then
    cat "$session_file"
    return 0
  fi
  return 1
}

create_session() {
  local title="${1:-Boss 主控对话}"
  local payload
  payload="$(request POST /api/sessions "$(json_payload title "$title")")"
  local session_id
  session_id="$(printf '%s' "$payload" | json_get "data.session.id")"
  save_session_id "$session_id"
  printf '%s\n' "$payload"
}

command="${1:-}"
shift || true

if [[ -z "$command" ]]; then
  usage
  exit 1
fi

require_tools

case "$command" in
  sessions)
    request GET /api/sessions | node -e 'const fs=require("fs"); const data=JSON.parse(fs.readFileSync(0,"utf8")); for (const session of data) console.log(`${session.id}\t${session.status}\t${session.title}`);'
    ;;
  create)
    create_session "${1:-Boss 主控对话}"
    ;;
  send)
    message="${1:-}"
    if [[ -z "$message" ]]; then
      echo "Missing message." >&2
      exit 1
    fi
    session_id="${2:-}"
    if [[ -z "$session_id" ]]; then
      session_id="$(load_session_id || true)"
    fi
    if [[ -z "$session_id" ]]; then
      session_json="$(create_session "Boss 主控对话")"
      session_id="$(printf '%s' "$session_json" | json_get "data.session.id")"
    fi
    request POST "/api/sessions/$session_id/messages" "$(json_message_payload "$message")"
    printf '\n'
    save_session_id "$session_id"
    ;;
  status)
    session_id="${1:-}"
    if [[ -z "$session_id" ]]; then
      session_id="$(load_session_id || true)"
    fi
    if [[ -z "$session_id" ]]; then
      echo "No session id found. Run create or send first." >&2
      exit 1
    fi
    request GET "/api/sessions/$session_id"
    printf '\n'
    ;;
  *)
    usage
    exit 1
    ;;
esac