#!/bin/bash
  #
  # Shared helpers for mapping reranker backends to isolated virtualenvs.
  #
  
  set -euo pipefail
  
  detect_rerank_backend() {
    local project_root="$1"
    local backend="${RERANK_BACKEND:-}"
  
    if [[ -n "${backend}" ]]; then
      printf '%s\n' "${backend}"
      return 0
    fi
  
    backend="$(
      awk '
        /^  rerank:$/ { in_rerank=1; next }
        in_rerank && /^  [^ ]/ { in_rerank=0 }
        in_rerank && /^    backend:/ {
          gsub(/"/, "", $2)
          print $2
          exit
        }
      ' "${project_root}/config/config.yaml"
    )"
  
    if [[ -z "${backend}" ]]; then
      backend="qwen3_vllm"
    fi
  
    printf '%s\n' "${backend}"
  }
  
  reranker_backend_venv_dir() {
    local project_root="$1"
    local backend="$2"
  
    case "${backend}" in

      qwen3_vllm) printf '%s/.venv-reranker\n' "${project_root}" ;;
      qwen3_vllm_score) printf '%s/.venv-reranker-score\n' "${project_root}" ;;

      jina_reranker_v3) printf '%s/.venv-reranker-jina\n' "${project_root}" ;;

      qwen3_gguf) printf '%s/.venv-reranker-gguf\n' "${project_root}" ;;

      qwen3_gguf_06b) printf '%s/.venv-reranker-gguf-06b\n' "${project_root}" ;;

      qwen3_transformers) printf '%s/.venv-reranker-transformers\n' "${project_root}" ;;

      qwen3_transformers_packed) printf '%s/.venv-reranker-transformers-packed\n' "${project_root}" ;;

      bge) printf '%s/.venv-reranker-bge\n' "${project_root}" ;;
      dashscope_rerank) printf '%s/.venv-reranker-dashscope\n' "${project_root}" ;;
      *) printf '%s/.venv-reranker-%s\n' "${project_root}" "${backend}" ;;
    esac
  }
  
  reranker_backend_requirements_file() {
    local project_root="$1"
    local backend="$2"
  
    case "${backend}" in

      qwen3_vllm) printf '%s/requirements_reranker_qwen3_vllm.txt\n' "${project_root}" ;;
      qwen3_vllm_score) printf '%s/requirements_reranker_qwen3_vllm_score.txt\n' "${project_root}" ;;

      jina_reranker_v3) printf '%s/requirements_reranker_jina_reranker_v3.txt\n' "${project_root}" ;;

      qwen3_gguf) printf '%s/requirements_reranker_qwen3_gguf.txt\n' "${project_root}" ;;

      qwen3_gguf_06b) printf '%s/requirements_reranker_qwen3_gguf_06b.txt\n' "${project_root}" ;;

      qwen3_transformers) printf '%s/requirements_reranker_qwen3_transformers.txt\n' "${project_root}" ;;

      qwen3_transformers_packed) printf '%s/requirements_reranker_qwen3_transformers_packed.txt\n' "${project_root}" ;;

      bge) printf '%s/requirements_reranker_bge.txt\n' "${project_root}" ;;
      dashscope_rerank) printf '%s/requirements_reranker_dashscope.txt\n' "${project_root}" ;;
      *) return 1 ;;
    esac
  }