# ==============================================================================
# Paper Search MCP Server - Environment Variables
# ==============================================================================
# Supports 14 academic platforms with unified search interface
# Platforms: arXiv, Web of Science, PubMed, Google Scholar, bioRxiv, medRxiv, 
# Semantic Scholar, IACR ePrint, Sci-Hub, ScienceDirect, Springer, Wiley, Scopus, Crossref

# ==============================================================================
# API KEYS CONFIGURATION
# ==============================================================================

# ------------------------------------------------------------------------------
# Web of Science (Clarivate) - REQUIRED
# ------------------------------------------------------------------------------
# Premium citation database with high-quality journal indexing
# Get API key: https://developer.clarivate.com/apis
# Pricing: Paid subscription required
# Rate limit: Depends on subscription level
# Web of Science defaults to Starter v2 and uses WOS_API_KEY.
# Expanded is optional and requires its own product key.
WOS_API_KEY=your_web_of_science_api_key_here
WOS_EXPANDED_API_KEY=
WOS_STARTER_VERSION=v2
WOS_STARTER_RPS=1
WOS_STARTER_DAILY_LIMIT=50
WOS_EXPANDED_RPS=2
# Full Record records/day; 0 means unlimited local accounting.
WOS_EXPANDED_FULL_RECORD_BUDGET=0
# Current Swagger server; override only when your Clarivate tenant requires it.
WOS_EXPANDED_BASE_URL=https://api.clarivate.com/api/wos

# ------------------------------------------------------------------------------
# PubMed/NCBI E-utilities - OPTIONAL (but recommended)
# ------------------------------------------------------------------------------
# Biomedical literature database
# Without API key: 3 requests/second limit
# With API key: 10 requests/second limit
# Get API key: https://ncbiinsights.ncbi.nlm.nih.gov/2017/11/02/new-api-keys-for-the-e-utilities/
# Pricing: Free
PUBMED_API_KEY=your_ncbi_api_key_here

# ------------------------------------------------------------------------------
# Semantic Scholar - OPTIONAL (increases rate limits)
# ------------------------------------------------------------------------------
# AI-powered academic search with semantic understanding
# Without API key: ~20 requests/minute (free tier)
# With API key: ~180 requests/minute (partner tier)
# Get API key: https://www.semanticscholar.org/product/api
# Pricing: Free for academic use
SEMANTIC_SCHOLAR_API_KEY=your_semantic_scholar_api_key_here

# ------------------------------------------------------------------------------
# Elsevier APIs - separate ScienceDirect and Scopus contracts
# ------------------------------------------------------------------------------
# ScienceDirect Search API v2 and Scopus abstract/reference operations use the
# general Elsevier application key. The provider's entitlements still apply.
# Get a key: https://dev.elsevier.com/apikey/manage
ELSEVIER_API_KEY=your_elsevier_api_key_here
# Optional dedicated key for Scopus Search API. It takes precedence only for
# Scopus search requests; it does not replace ELSEVIER_API_KEY for abstract or
# reference operations. If blank, Scopus search falls back to ELSEVIER_API_KEY.
SCOPUS_SEARCH_API_KEY=

# ------------------------------------------------------------------------------
# Springer Nature API - REQUIRED for Springer
# ------------------------------------------------------------------------------
# Dual API system:
# - Metadata API v2: Search all Springer content (subscription + open access)
#   Endpoint: https://api.springernature.com/meta/v2/json
# - OpenAccess API: Search and download open access papers only
#   Endpoint: https://api.springernature.com/openaccess/json
#   Note: OpenAccess API may require special permissions on your API key
#
# Get API key: https://dev.springernature.com/signup
# Documentation: https://dev.springernature.com/
# Pricing: Free with 5000 requests/day limit (shared between both APIs)
# Rate limit: ~200 requests/hour (conservative)
#
# Primary API key (required - works for Metadata API v2)
SPRINGER_API_KEY=your_springer_api_key_here
#
# Optional: Separate OpenAccess API key (if different from main key)
# Only set this if you have a separate key specifically for OpenAccess API
# SPRINGER_OPENACCESS_API_KEY=your_openaccess_api_key_here

# ------------------------------------------------------------------------------
# Wiley Text and Data Mining (TDM) - REQUIRED for Wiley
# ------------------------------------------------------------------------------
# Access to Wiley Online Library for text and data mining
# Get TDM token: https://onlinelibrary.wiley.com/library-info/resources/text-and-datamining
# Pricing: Requires institutional affiliation or subscription
# Rate limit: ~100 requests/hour (conservative estimate)
WILEY_TDM_TOKEN=your_wiley_tdm_token_here

# ==============================================================================
# PLATFORM STATUS SUMMARY
# ==============================================================================
# 
# Platform          | API Key    | Features                      | Best For
# ------------------|------------|-------------------------------|------------------
# arXiv             | ✅ Free    | Preprints, PDF download       | Physics, CS, Math
# Web of Science    | 🔴 Required| Citation analysis, metrics   | Impact research
# PubMed            | 🟡 Optional| Medical literature            | Biomedical
# Google Scholar    | ✅ Free    | Comprehensive coverage        | General search
# bioRxiv           | ✅ Free    | Biology preprints, PDF        | Biology research
# medRxiv           | ✅ Free    | Medical preprints, PDF        | Medical research
# Semantic Scholar  | 🟡 Optional| AI-powered search, citations  | CS, AI research
# IACR ePrint       | ✅ Free    | Cryptography papers, PDF      | Cryptography
# Sci-Hub          | Opt-in    | Controlled DOI HTML adapter   | Authorized/public content only
# ScienceDirect     | 🔴 Required| Search API v2                 | Metadata/search
# Springer          | 🔴 Required| Dual API (Meta+OpenAccess)    | Books & journals
# Wiley             | 🔴 Required| TDM API, full text mining     | Data mining
# Scopus            | 🔴 Required| Search + abstract/citations  | Bibliometrics
#                   |            | Dedicated search key optional; general key for details
# Crossref          | ✅ Free    | DOI metadata and citations   | General discovery
#
# Legend: ✅ No key needed | 🟡 Optional key | 🔴 Key required

# ==============================================================================
# SERVER CONFIGURATION
# ==============================================================================
NODE_ENV=production
LOG_LEVEL=info

# Download Configuration
DEFAULT_DOWNLOAD_PATH=./downloads
MAX_FILE_SIZE_MB=100

# Rate Limiting
RATE_LIMIT_REQUESTS_PER_MINUTE=60
RATE_LIMIT_BURST=10

# ------------------------------------------------------------------------------
# ScrapingAnt public-page fetcher (optional; never used for Clarivate API calls)
# A key alone does not authorize paid retrieval; opt in explicitly.
# Browser escalation is disabled by default and residential access is rejected.
# ------------------------------------------------------------------------------
SCRAPINGANT_API_KEY=
SCRAPINGANT_ENABLED=false
SCRAPINGANT_ALLOW_BROWSER_ESCALATION=false
SCRAPINGANT_MAX_CREDITS_PER_OPERATION=50
SCRAPINGANT_MAX_CREDITS_PER_REQUEST=10
SCRAPINGANT_MAX_CONCURRENCY=1
SCRAPINGANT_PROXY_TYPE=datacenter

# ------------------------------------------------------------------------------
# Controlled Sci-Hub HTML adapter (disabled by default)
# ------------------------------------------------------------------------------
SCIHUB_ENABLED=false
SCIHUB_FETCH_MODE=fallback
SCIHUB_MIRRORS=
SCIHUB_HEALTHCHECK_CONCURRENCY=3