#!/bin/bash
# Install OrderPy Bridge daemon (systemd). Run with sudo.
set -e

INSTALL_PREFIX="${INSTALL_PREFIX:-/opt/orderpy-bridge}"
CONFIG_DIR="/etc/orderpy-bridge"
DATA_DIR="/var/lib/orderpy-bridge"
SERVICE_USER="orderpy-bridge"
SERVICE_GROUP="orderpy-bridge"

# Optional colors and formatting (disable if not a tty or TERM is dumb)
if [[ -t 1 ]] && [[ "${TERM:-dumb}" != "dumb" ]]; then
  RED="$(tput setaf 1 2>/dev/null || true)"
  GREEN="$(tput setaf 2 2>/dev/null || true)"
  YELLOW="$(tput setaf 3 2>/dev/null || true)"
  BOLD="$(tput bold 2>/dev/null || true)"
  SGR0="$(tput sgr0 2>/dev/null || true)"
else
  RED="" GREEN="" YELLOW="" BOLD="" SGR0=""
fi

# Preflight: print check label (no newline), then call ok_line or fail_line with result (overwrites line with \r)
preflight_check() { printf "  %-28s " "$1"; }
ok_line()   { printf "\r  %-28s ${GREEN}[ OK ]${SGR0}   %s\n" "$PREFLIGHT_LABEL" "$1"; }
fail_line() { printf "\r  %-28s ${RED}[ FAIL ]${SGR0} %s\n" "$PREFLIGHT_LABEL" "$1" >&2; return 1; }

# Resolve orderpy-bridge repo root (directory containing bridge_core and daemon/)
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
BRIDGE_ROOT="$SCRIPT_DIR"
while [[ -n "$BRIDGE_ROOT" ]]; do
  if [[ -d "$BRIDGE_ROOT/bridge_core" ]] && [[ -f "$BRIDGE_ROOT/daemon/main.py" ]]; then
    break
  fi
  BRIDGE_ROOT="${BRIDGE_ROOT%/*}"
  [[ "$BRIDGE_ROOT" == "${BRIDGE_ROOT%/*}" ]] && BRIDGE_ROOT=""
done
if [[ -z "$BRIDGE_ROOT" ]] || [[ ! -d "$BRIDGE_ROOT/bridge_core" ]]; then
  echo "${RED}Error:${SGR0} Run from orderpy-bridge repo (bridge_core and daemon/ must exist)." >&2
  exit 1
fi

if [[ "$(id -u)" -ne 0 ]]; then
  echo "${RED}Error:${SGR0} This script must be run with sudo." >&2
  exit 1
fi

# --- Preflight checks ---
echo ""
echo "${BOLD}Preflight checks${SGR0}"
PREFLIGHT_FAIL=0

# Python 3.11+
PREFLIGHT_LABEL="Python 3.11+"
preflight_check "$PREFLIGHT_LABEL"
PYVER=""
if command -v python3 >/dev/null 2>&1; then
  PYVER="$(python3 -c 'import sys; print(f"{sys.version_info.major}.{sys.version_info.minor}")' 2>/dev/null)" || true
fi
if [[ -z "$PYVER" ]]; then
  fail_line "python3 not found. Install Python 3.11+ (e.g. apt install python3 python3-venv)." || PREFLIGHT_FAIL=1
else
  MAJOR="${PYVER%%.*}"; MINOR="${PYVER#*.}"; MINOR="${MINOR%%.*}"
  if [[ "$MAJOR" -lt 3 ]] || { [[ "$MAJOR" -eq 3 ]] && [[ "$MINOR" -lt 11 ]]; }; then
    fail_line "Python $PYVER found; 3.11+ required. Install a newer python3." || PREFLIGHT_FAIL=1
  else
    ok_line "Python $PYVER"
  fi
fi

# python3-venv
PREFLIGHT_LABEL="python3-venv"
preflight_check "$PREFLIGHT_LABEL"
if python3 -m venv --help >/dev/null 2>&1; then
  ok_line "available"
else
  fail_line "not available. Install it (e.g. apt install python3-venv)." || PREFLIGHT_FAIL=1
fi

# pip or ensurepip (venv will get pip via ensurepip or get-pip.py)
PREFLIGHT_LABEL="pip / ensurepip"
preflight_check "$PREFLIGHT_LABEL"
if python3 -m pip --version >/dev/null 2>&1 || python3 -c 'import ensurepip' 2>/dev/null; then
  ok_line "available"
else
  fail_line "pip not found. Install python3-pip or python3-venv (e.g. apt install python3-venv python3-pip)." || PREFLIGHT_FAIL=1
fi

# systemd
PREFLIGHT_LABEL="systemd"
preflight_check "$PREFLIGHT_LABEL"
if command -v systemctl >/dev/null 2>&1 && [[ -d /run/systemd/system ]]; then
  ok_line "available"
else
  fail_line "not found or not running. This installer is for systemd-based systems." || PREFLIGHT_FAIL=1
fi

# Write access to target dirs
PREFLIGHT_LABEL="Write access (prefix)"
preflight_check "$PREFLIGHT_LABEL"
PARENT="$(dirname "$INSTALL_PREFIX")"
if [[ -w "$PARENT" ]] || [[ ! -e "$PARENT" ]]; then
  ok_line "Can install to $INSTALL_PREFIX"
else
  fail_line "No write access to $(dirname "$INSTALL_PREFIX"). Set INSTALL_PREFIX or fix permissions." || PREFLIGHT_FAIL=1
fi

PREFLIGHT_LABEL="Config directory"
preflight_check "$PREFLIGHT_LABEL"
if [[ -w /etc ]] || [[ -d "$CONFIG_DIR" && -w "$CONFIG_DIR" ]]; then
  ok_line "/etc/orderpy-bridge can be created"
else
  fail_line "Cannot create $CONFIG_DIR. Run with sudo." || PREFLIGHT_FAIL=1
fi

echo ""
if [[ "$PREFLIGHT_FAIL" -ne 0 ]]; then
  echo "${RED}${BOLD}Preflight failed.${SGR0} Fix the issues above and run the script again." >&2
  exit 1
fi
echo "${GREEN}All preflight checks passed.${SGR0}"
echo ""

# Installation runs in background; we show a progress bar until it finishes.
ENV_FILE="$CONFIG_DIR/orderpy-bridge.env"
INSTALL_LOG="$(mktemp)"
INSTALL_EXIT_FILE="$(mktemp)"
trap 'rm -f "$INSTALL_LOG" "$INSTALL_EXIT_FILE"' EXIT

do_install() {
  set +e
  # User/group
  if ! getent group "$SERVICE_GROUP" >/dev/null; then
    groupadd --system "$SERVICE_GROUP"
  fi
  if ! getent passwd "$SERVICE_USER" >/dev/null; then
    useradd --system --no-create-home --gid "$SERVICE_GROUP" "$SERVICE_USER"
  fi
  # Directories
  install -d -m 755 "$CONFIG_DIR"
  install -d -m 750 -o "$SERVICE_USER" -g "$SERVICE_GROUP" "$DATA_DIR"
  install -d -m 755 "$(dirname "$INSTALL_PREFIX")"
  install -d -m 755 -o "$SERVICE_USER" -g "$SERVICE_GROUP" "$INSTALL_PREFIX"
  # Config: env file only if missing
  if [[ ! -f "$ENV_FILE" ]]; then
    install -m 640 -o root -g "$SERVICE_GROUP" "$BRIDGE_ROOT/daemon/orderpy-bridge.env.example" "$ENV_FILE"
  fi
  # Application files
  cp -r "$BRIDGE_ROOT/bridge_core" "$INSTALL_PREFIX/"
  install -m 644 "$BRIDGE_ROOT/daemon/main.py" "$INSTALL_PREFIX/"
  install -m 644 "$BRIDGE_ROOT/daemon/requirements.txt" "$INSTALL_PREFIX/"
  chown -R "$SERVICE_USER:$SERVICE_GROUP" "$INSTALL_PREFIX"

  # Python venv: ensure pip is available, then install deps and verify uvicorn
  if [[ ! -x "$INSTALL_PREFIX/venv/bin/uvicorn" ]]; then
    python3 -m venv "$INSTALL_PREFIX/venv"
    VENV_PYTHON="$INSTALL_PREFIX/venv/bin/python"

    # Ensure pip in venv (some minimal python3-venv installs create venv without pip)
    if ! "$VENV_PYTHON" -m pip --version >/dev/null 2>&1; then
      if "$VENV_PYTHON" -m ensurepip --upgrade 2>/dev/null; then
        : # pip now available
      else
        GET_PIP="$(mktemp)"
        if curl -sSf -o "$GET_PIP" "https://bootstrap.pypa.io/get-pip.py" && "$VENV_PYTHON" "$GET_PIP"; then
          rm -f "$GET_PIP"
        else
          rm -f "$GET_PIP"
          echo "FATAL: Could not install pip into venv (ensurepip failed and get-pip.py failed or unavailable)." >&2
          exit 1
        fi
      fi
    fi

    "$VENV_PYTHON" -m pip install --disable-pip-version-check -q -r "$INSTALL_PREFIX/requirements.txt" || {
      echo "FATAL: pip install -r requirements.txt failed." >&2
      exit 1
    }

    if [[ ! -x "$INSTALL_PREFIX/venv/bin/uvicorn" ]]; then
      echo "FATAL: uvicorn not found after pip install. Check requirements.txt and network." >&2
      exit 1
    fi

    chown -R "$SERVICE_USER:$SERVICE_GROUP" "$INSTALL_PREFIX/venv"
  fi

  # systemd unit
  install -m 644 "$BRIDGE_ROOT/daemon/systemd/orderpy-bridge.service" /etc/systemd/system/
  systemctl daemon-reload
  exit 0
}

( do_install; r=$?; echo $r > "$INSTALL_EXIT_FILE"; exit $r ) >> "$INSTALL_LOG" 2>&1 &
INSTALL_PID=$!

# Progress bar (indeterminate: moving cursor)
BAR_W=24
bar_pos=0
printf "\n  Installing to %s\n  " "$INSTALL_PREFIX"
while kill -0 "$INSTALL_PID" 2>/dev/null; do
  bar=""
  for (( i=0; i<BAR_W; i++ )); do
    [[ $i -eq $bar_pos ]] && bar="${bar}>" || bar="${bar} "
  done
  printf "\r  [%s] Installing... " "$bar"
  bar_pos=$(( (bar_pos + 1) % BAR_W ))
  sleep 0.08
done
wait "$INSTALL_PID" 2>/dev/null || true
EXIT_CODE=0
[[ -f "$INSTALL_EXIT_FILE" ]] && read -r EXIT_CODE < "$INSTALL_EXIT_FILE" || true

if [[ "$EXIT_CODE" -ne 0 ]]; then
  printf "\r  [%*s] ${RED}Installation failed.${SGR0}\n" "$BAR_W" " "
  echo ""
  echo "Last lines of install log:"
  tail -n 20 "$INSTALL_LOG" | sed 's/^/  /'
  cp "$INSTALL_LOG" /tmp/orderpy-bridge-install.log 2>/dev/null || true
  echo ""
  echo "Full log: /tmp/orderpy-bridge-install.log"
  exit "$EXIT_CODE"
fi

printf "\r  [%s] ${GREEN}Done!${SGR0}          \n\n" "$(printf '%*s' "$BAR_W" '' | tr ' ' '=')"
echo "If this is a fresh install, edit $ENV_FILE and set ORDERPY_CLOUD_URL, ORDERPY_ALLOWED_ORIGINS."
echo ""
echo "Next steps:"
echo "  sudo systemctl enable --now orderpy-bridge"
echo "  sudo systemctl status orderpy-bridge"