# conveniencelist.pyx
# defines int arrays in C, with some convenience methods
# for reading arrays directly as globs directly from disk.
# Adam Lopez <alopez@cs.umd.edu>

from libc.stdio cimport FILE, fopen, fread, fwrite, fclose
from libc.stdlib cimport malloc, realloc, free
from libc.string cimport memset, strcpy, strlen

cdef class CFloatList:

	def __cinit__(self, size=0, increment=1, initial_len=0):
		if initial_len > size:
			size = initial_len
		self.arr = <float*> malloc(size*sizeof(float))
		memset(self.arr, 0, initial_len*sizeof(float))


	def __init__(self, size=0, increment=1, initial_len=0):
		self.size = size
		if initial_len > size:
			self.size = initial_len
		self.increment = increment
		self.len = initial_len


	def __dealloc__(self):
		free(self.arr)


	def __getitem__(self, i):
		j = i
		if i<0: 
			j = self.len + i
		if j<0 or j>=self.len:
			raise IndexError("Requested index %d of %d-length FloatList" % (i, self.len))
		return self.arr[j]


	cdef void set(self, int i, float v):
		j = i
		if i<0: 
			j = self.len + i
		if j<0 or j>=self.len:
			raise IndexError("Requested index %d of %d-length FloatList" % (i, self.len))
		self.arr[j] = v
	
	def __setitem__(self, i, val):
		self.set(i, val)

	def __len__(self):
		return self.len


	def append(self, float val):
		if self.len == self.size:
			self.size = self.size + self.increment
			self.arr = <float*> realloc(self.arr, self.size*sizeof(float))
		self.arr[self.len] = val
		self.len = self.len + 1


	cdef void write_handle(self, FILE* f):
		fwrite(&(self.len), sizeof(float), 1, f)
		fwrite(self.arr, sizeof(float), self.len, f)


	def write(self, filename):
		cdef FILE* f
		cdef bytes bfilename = filename
		cdef char* cfilename = bfilename
		f = fopen(cfilename, "w")
		self.write_handle(f)
		fclose(f)


	cdef void read_handle(self, FILE* f):
		free(self.arr)
		fread(&(self.len), sizeof(float), 1, f)
		self.arr = <float*> malloc(self.len * sizeof(float))
		self.size = self.len
		fread(self.arr, sizeof(float), self.len, f)


	def read(self, filename):
		cdef FILE* f
		cdef bytes bfilename = filename
		cdef char* cfilename = bfilename
		f = fopen(cfilename, "r")
		self.read_handle(f)
		fclose(f)