Bibliography Processing

class BibData(NamedTuple):
    """
    Information about a collection of bib files.
    
    Attributes:
        encoding: Encoding used for all bib files
        bibfiles: Map from file paths to file information
        data: Parsed bibliography data from pybtex
    """
    encoding: str
    bibfiles: Dict[Path, BibFile]
    data: BibliographyData  # From pybtex

class BibFile(NamedTuple):
    """
    Information about a parsed bib file.
    
    Attributes:
        mtime: File modification time when last parsed
        keys: Set of citation keys in this file (as ordered dict)
    """
    mtime: float
    keys: Dict[str, None]

def parse_bibdata(bibfilenames: List[Path], encoding: str) -> BibData:
    """
    Parse bibliography files with given encoding.
    
    Parameters:
        bibfilenames: List of bibliography file paths to parse
        encoding: Text encoding to use when reading files
        
    Returns:
        Parsed bibliography data containing all entries
        
    Raises:
        BibliographyDataError: If bibliography files contain syntax errors
    """

def is_bibdata_outdated(
    bibdata: BibData, 
    bibfilenames: List[Path], 
    encoding: str
) -> bool:
    """
    Check if bibliography data needs to be reparsed.
    
    Parameters:
        bibdata: Current bibliography data
        bibfilenames: List of current bibliography files
        encoding: Current encoding setting
        
    Returns:
        True if data is outdated and needs reparsing
    """

def process_bibdata(
    bibdata: BibData,
    bibfilenames: List[Path], 
    encoding: str
) -> BibData:
    """
    Parse bibliography files and store parsed data with caching.
    
    Only reparses if files have changed, encoding changed, or file list changed.
    
    Parameters:
        bibdata: Previous bibliography data (for caching)
        bibfilenames: List of bibliography file paths
        encoding: Text encoding for files
        
    Returns:
        Updated bibliography data (may be cached if unchanged)
    """

def get_mtime(bibfilename: Path) -> float:
    """
    Get file modification time, returning -inf if file doesn't exist.
    
    Parameters:
        bibfilename: Path to bibliography file
        
    Returns:
        Modification time as float, or -math.inf if file missing
    """

class CitationTarget(NamedTuple):
    """
    Citation key with optional pre-text and post-text.
    
    Attributes:
        key: The bibliography key to cite
        pre: Optional text to appear before citation
        post: Optional text to appear after citation
    """
    key: str
    pre: str
    post: str

def parse_citation_targets(targets: str, pos: int = 0) -> Iterable[CitationTarget]:
    """
    Parse citation target string into citation keys with optional pre/post text.
    
    Supports formats:
        key - Simple key citation
        {pre}key - Key with pre-text
        key{post} - Key with post-text  
        {pre}key{post} - Key with both pre and post text
        key1,key2,key3 - Multiple keys
        
    Parameters:
        targets: String containing citation targets
        pos: Starting position for parsing (used internally for recursion)
        
    Returns:
        Iterable of CitationTarget objects
        
    Raises:
        ValueError: If citation target format is malformed
    """

def _make_ids(docname: str, lineno: int, ids: Set[str], raw_id: str) -> List[str]:
    """
    Generate unique IDs for citations and bibliographies.
    
    Parameters:
        docname: Document name for warning location
        lineno: Line number for warning location  
        ids: Set of existing IDs to check for conflicts
        raw_id: Raw ID template string
        
    Returns:
        List containing the generated ID, or empty list if duplicate detected
        
    Side Effects:
        - Adds generated ID to ids set if successful
        - Logs warning if duplicate ID detected
    """

from pathlib import Path
from sphinxcontrib.bibtex.bibfile import parse_bibdata, process_bibdata

# Parse bibliography files
bibfiles = [Path("refs.bib"), Path("additional.bib")]
bibdata = parse_bibdata(bibfiles, "utf-8")

# Access parsed data
for key, entry in bibdata.data.entries.items():
    print(f"Key: {key}, Title: {entry.fields.get('title', 'No title')}")

# First call - parses files
bibdata = process_bibdata(BibData("", {}, BibliographyData()), bibfiles, "utf-8")

# Second call - uses cache since files unchanged
bibdata = process_bibdata(bibdata, bibfiles, "utf-8")  # Fast, uses cache

from sphinxcontrib.bibtex.citation_target import parse_citation_targets

# Simple keys
targets = list(parse_citation_targets("smith2020,jones2019"))
# [CitationTarget(key='smith2020', pre='', post=''), 
#  CitationTarget(key='jones2019', pre='', post='')]

# With pre/post text  
targets = list(parse_citation_targets("{see}smith2020{for details}"))
# [CitationTarget(key='smith2020', pre='see', post='for details')]

from sphinxcontrib.bibtex.bibfile import get_mtime, is_bibdata_outdated

# Check if files need reparsing
if is_bibdata_outdated(current_bibdata, bibfiles, "utf-8"):
    print("Bibliography files have changed, reparsing...")
    bibdata = parse_bibdata(bibfiles, "utf-8")
else:
    print("Bibliography files unchanged, using cache")