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

PACKAGE_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd -P)"
STOW_BIN="${STOW_BIN:-stow}"
SETUP_SHELL=1

usage() {
  cat <<'EOF'
Использование: ./install.sh [--no-shell-setup]

  --no-shell-setup  не изменять ~/.bashrc
EOF
}

while [ "$#" -gt 0 ]; do
  case "$1" in
    --no-shell-setup)
      SETUP_SHELL=0
      ;;
    -h|--help)
      usage
      exit 0
      ;;
    *)
      echo "Ошибка: неизвестный параметр: $1" >&2
      usage >&2
      exit 2
      ;;
  esac
  shift
done

SOURCES=(
  "$PACKAGE_DIR/.local/bin/proxy-client"
  "$PACKAGE_DIR/.config/proxy-client/shell.bash"
  "$PACKAGE_DIR/.config/proxy-client/examples"
)
TARGETS=(
  "$HOME/.local/bin/proxy-client"
  "$HOME/.config/proxy-client/shell.bash"
  "$HOME/.config/proxy-client/examples"
)
STOW_IGNORE_PATTERNS=(
  '^\.local/bin/proxy-client$'
  '^\.config/proxy-client/shell\.bash$'
  '^\.config/proxy-client/examples$'
)

source_errors=()
[ -x "${SOURCES[0]}" ] || source_errors+=("${SOURCES[0]}")
[ -f "${SOURCES[1]}" ] || source_errors+=("${SOURCES[1]}")
[ -d "${SOURCES[2]}" ] || source_errors+=("${SOURCES[2]}")
if [ "${#source_errors[@]}" -gt 0 ]; then
  echo "Ошибка: отсутствуют обязательные файлы исходного пакета:" >&2
  printf '  %s\n' "${source_errors[@]}" >&2
  exit 1
fi

"${SOURCES[0]}" --help >/dev/null
bash -n "${SOURCES[1]}"

SHELL_BLOCK_START='# >>> proxy-client >>>'
SHELL_BLOCK_END='# <<< proxy-client <<<'
SHELL_SETUP_NEEDED=0
BASH_CUSTOM_HAS_MODULE=0
SHELL_PATH_NEEDED=1
SHELL_SOURCE_NEEDED=1
SHELL_BLOCK_CONFLICT=0
if [ "$SETUP_SHELL" -eq 1 ]; then
  if [ -f "$HOME/.bash_custom" ] \
    && grep -Fq 'proxy-client/shell.bash' "$HOME/.bash_custom"; then
    BASH_CUSTOM_HAS_MODULE=1
    SHELL_SOURCE_NEEDED=0
  fi

  bashrc_start_count=0
  bashrc_end_count=0
  if [ -f "$HOME/.bashrc" ]; then
    bashrc_start_count="$(
      grep -Fxc "$SHELL_BLOCK_START" "$HOME/.bashrc" || true
    )"
    bashrc_end_count="$(
      grep -Fxc "$SHELL_BLOCK_END" "$HOME/.bashrc" || true
    )"
    if grep -Fq 'export PATH="$HOME/.local/bin:$PATH"' "$HOME/.bashrc"; then
      SHELL_PATH_NEEDED=0
    fi
  fi

  if [ "$bashrc_start_count" -eq 0 ] && [ "$bashrc_end_count" -eq 0 ]; then
    if [ "$SHELL_PATH_NEEDED" -eq 1 ] \
      || [ "$SHELL_SOURCE_NEEDED" -eq 1 ]; then
      SHELL_SETUP_NEEDED=1
    fi
  elif [ "$bashrc_start_count" -eq 1 ] \
    && [ "$bashrc_end_count" -eq 1 ] \
    && [ "$SHELL_PATH_NEEDED" -eq 0 ] \
    && { [ "$BASH_CUSTOM_HAS_MODULE" -eq 1 ] \
      || grep -Fq 'proxy-client/shell.bash' "$HOME/.bashrc"; }; then
    :
  else
    SHELL_BLOCK_CONFLICT=1
  fi
fi

conflicts=()
missing_targets=0
stow_ignore_args=()
PARENT_DIRS=(
  "$HOME/.local"
  "$HOME/.local/bin"
  "$HOME/.config"
  "$HOME/.config/proxy-client"
)
for parent_dir in "${PARENT_DIRS[@]}"; do
  if { [ -e "$parent_dir" ] || [ -L "$parent_dir" ]; } \
    && { [ ! -d "$parent_dir" ] || [ -L "$parent_dir" ]; }; then
    conflicts+=("$parent_dir")
  fi
done

for index in "${!TARGETS[@]}"; do
  target="${TARGETS[$index]}"
  source_path="${SOURCES[$index]}"
  if [ -e "$target" ] || [ -L "$target" ]; then
    if [ ! -L "$target" ] \
      || [ "$(readlink -f "$target" 2>/dev/null || true)" != "$source_path" ]; then
      conflicts+=("$target")
    else
      stow_ignore_args+=("--ignore=${STOW_IGNORE_PATTERNS[$index]}")
    fi
  else
    missing_targets=$((missing_targets + 1))
  fi
done

if [ "$SHELL_SETUP_NEEDED" -eq 1 ] \
  && { [ -e "$HOME/.bashrc" ] || [ -L "$HOME/.bashrc" ]; } \
  && [ ! -f "$HOME/.bashrc" ]; then
  conflicts+=("$HOME/.bashrc")
fi
if [ "$SHELL_BLOCK_CONFLICT" -eq 1 ]; then
  conflicts+=("$HOME/.bashrc")
fi

if [ "${#conflicts[@]}" -gt 0 ]; then
  echo "Ошибка: найдены конфликтующие пути:" >&2
  printf '  %s\n' "${conflicts[@]}" >&2
  echo "Разберите их вручную и повторите установку." >&2
  exit 1
fi

mkdir -p "$HOME/.local/bin" "$HOME/.config/proxy-client"

if command -v "$STOW_BIN" >/dev/null 2>&1; then
  echo "Установка с помощью Stow."
  if [ "$missing_targets" -gt 0 ]; then
    "$STOW_BIN" --dir="$(dirname "$PACKAGE_DIR")" --target="$HOME" \
      "${stow_ignore_args[@]}" \
      "$(basename "$PACKAGE_DIR")"
  fi
else
  echo "Установка без Stow: создаю символические ссылки напрямую."
  for index in "${!TARGETS[@]}"; do
    target="${TARGETS[$index]}"
    source_path="${SOURCES[$index]}"
    if [ ! -L "$target" ]; then
      ln -s "$source_path" "$target"
    fi
  done
fi

"$HOME/.local/bin/proxy-client" --help >/dev/null
bash -n "$HOME/.config/proxy-client/shell.bash"

if [ "$SHELL_SETUP_NEEDED" -eq 1 ]; then
  cat >> "$HOME/.bashrc" <<'EOF'

# >>> proxy-client >>>
EOF
  if [ "$SHELL_PATH_NEEDED" -eq 1 ]; then
    cat >> "$HOME/.bashrc" <<'EOF'
case ":$PATH:" in
  *":$HOME/.local/bin:"*) ;;
  *)
    export PATH="$HOME/.local/bin:$PATH"
    ;;
esac
EOF
  fi
  if [ "$SHELL_SOURCE_NEEDED" -eq 1 ]; then
    cat >> "$HOME/.bashrc" <<'EOF'
[ -f "$HOME/.config/proxy-client/shell.bash" ] && source "$HOME/.config/proxy-client/shell.bash"
EOF
  fi
  cat >> "$HOME/.bashrc" <<'EOF'
# <<< proxy-client <<<
EOF
elif [ "$SETUP_SHELL" -eq 0 ]; then
  echo "Настройка Bash пропущена (--no-shell-setup)."
fi

if [ "$SETUP_SHELL" -eq 1 ]; then
  RELOAD_COMMAND='source ~/.bashrc'
else
  RELOAD_COMMAND='source ~/.config/proxy-client/shell.bash'
fi

cat <<EOF
proxy-client установлен.
Исходный каталог должен оставаться по постоянному пути:
  $PACKAGE_DIR
Примените настройки в текущей сессии: $RELOAD_COMMAND
Настройка режима описана в $PACKAGE_DIR/README.md.
EOF