pyserveX/pyserve/_path_matcher.pyx

# cython: language_level=3
# cython: boundscheck=False
# cython: wraparound=False
# cython: cdivision=True
"""
Fast path matching module for PyServe.

This Cython module provides optimized path matching operations
for ASGI mount routing, significantly reducing overhead on hot paths.
"""

from cpython.object cimport PyObject


cdef class FastMountedPath:
    cdef:
        str _path
        str _path_with_slash
        Py_ssize_t _path_len
        bint _is_root
        public str name
        public bint strip_path
    
    def __cinit__(self):
        self._path = ""
        self._path_with_slash = "/"
        self._path_len = 0
        self._is_root = 1
        self.name = ""
        self.strip_path = 1
    
    def __init__(self, str path, str name="", bint strip_path=True):
        cdef Py_ssize_t path_len
        
        path_len = len(path)
        if path_len > 1 and path[path_len - 1] == '/':
            path = path[:path_len - 1]
        
        self._path = path
        self._path_len = len(path)
        self._is_root = 1 if (path == "" or path == "/") else 0
        self._path_with_slash = path + "/" if self._is_root == 0 else "/"
        self.name = name if name else path
        self.strip_path = 1 if strip_path else 0
    
    @property
    def path(self) -> str:
        return self._path
    
    cpdef bint matches(self, str request_path):
        cdef Py_ssize_t req_len
        
        if self._is_root:
            return 1
        
        req_len = len(request_path)
        
        if req_len < self._path_len:
            return 0
        
        if req_len == self._path_len:
            return 1 if request_path == self._path else 0
        
        if request_path[self._path_len] == '/':
            return 1 if request_path[:self._path_len] == self._path else 0
        
        return 0
    
    cpdef str get_modified_path(self, str original_path):
        cdef str new_path
        
        if not self.strip_path:
            return original_path
        
        if self._is_root:
            return original_path
        
        new_path = original_path[self._path_len:]
        
        if not new_path:
            return "/"
        
        return new_path
    
    def __repr__(self):
        return f"FastMountedPath(path={self._path!r}, name={self.name!r})"


def _get_path_len_neg(mount):
    return -len(mount.path)


cdef class FastMountManager:
    cdef:
        list _mounts
        int _mount_count
    
    def __cinit__(self):
        self._mounts = []
        self._mount_count = 0
    
    def __init__(self):
        self._mounts = []
        self._mount_count = 0
    
    cpdef void add_mount(self, FastMountedPath mount):
        self._mounts.append(mount)
        self._mounts = sorted(self._mounts, key=_get_path_len_neg, reverse=False)
        self._mount_count = len(self._mounts)
    
    cpdef FastMountedPath get_mount(self, str request_path):
        cdef:
            int i
            FastMountedPath mount
        
        for i in range(self._mount_count):
            mount = <FastMountedPath>self._mounts[i]
            if mount.matches(request_path):
                return mount
        
        return None
    
    cpdef bint remove_mount(self, str path):
        cdef:
            int i
            Py_ssize_t path_len
            FastMountedPath mount
        
        path_len = len(path)
        if path_len > 1 and path[path_len - 1] == '/':
            path = path[:path_len - 1]
        
        for i in range(self._mount_count):
            mount = <FastMountedPath>self._mounts[i]
            if mount._path == path:
                del self._mounts[i]
                self._mount_count -= 1
                return 1
        
        return 0
    
    @property
    def mounts(self) -> list:
        return list(self._mounts)
    
    @property 
    def mount_count(self) -> int:
        return self._mount_count
    
    cpdef list list_mounts(self):
        cdef:
            list result = []
            FastMountedPath mount
        
        for mount in self._mounts:
            result.append({
                "path": mount._path,
                "name": mount.name,
                "strip_path": mount.strip_path,
            })
        
        return result


cpdef bint path_matches_prefix(str request_path, str mount_path):
    cdef:
        Py_ssize_t mount_len = len(mount_path)
        Py_ssize_t req_len = len(request_path)
    
    if mount_len == 0 or mount_path == "/":
        return 1
    
    if req_len < mount_len:
        return 0
    
    if req_len == mount_len:
        return 1 if request_path == mount_path else 0
    
    if request_path[mount_len] == '/':
        return 1 if request_path[:mount_len] == mount_path else 0
    
    return 0


cpdef str strip_path_prefix(str original_path, str mount_path):
    cdef:
        Py_ssize_t mount_len = len(mount_path)
        str result
    
    if mount_len == 0 or mount_path == "/":
        return original_path
    
    result = original_path[mount_len:]
    
    if not result:
        return "/"
    
    return result


cpdef tuple match_and_modify_path(str request_path, str mount_path, bint strip_path=True):
    cdef:
        Py_ssize_t mount_len = len(mount_path)
        Py_ssize_t req_len = len(request_path)
        bint is_root = 1 if (mount_len == 0 or mount_path == "/") else 0
        str modified
    
    if is_root:
        return (True, request_path if strip_path else request_path)
    
    if req_len < mount_len:
        return (False, None)
    
    if req_len == mount_len:
        if request_path == mount_path:
            return (True, "/" if strip_path else request_path)
        return (False, None)
    
    if request_path[mount_len] == '/' and request_path[:mount_len] == mount_path:
        if strip_path:
            modified = request_path[mount_len:]
            return (True, modified if modified else "/")
        return (True, request_path)
    
    return (False, None)