"""
Process raw qstr file and output qstr data with length, hash and data bytes.

This script works with Python 2.6, 2.7, 3.3 and 3.4.
"""

from __future__ import print_function

import re
import sys

# Python 2/3 compatibility:
# - iterating through bytes is different
# - codepoint2name lives in a different module
import platform
if platform.python_version_tuple()[0] == '2':
 bytes_cons = lambda val, enc=None: bytearray(val)
 from htmlentitydefs import codepoint2name
elif platform.python_version_tuple()[0] == '3':
 bytes_cons = bytes
 from html.entities import codepoint2name
# end compatibility code

codepoint2name[ord('-')] = 'hyphen';

# add some custom names to map characters that aren't in HTML
codepoint2name[ord(' ')] = 'space'
codepoint2name[ord('\'')] = 'squot'
codepoint2name[ord(',')] = 'comma'
codepoint2name[ord('.')] = 'dot'
codepoint2name[ord(':')] = 'colon'
codepoint2name[ord(';')] = 'semicolon'
codepoint2name[ord('/')] = 'slash'
codepoint2name[ord('%')] = 'percent'
codepoint2name[ord('#')] = 'hash'
codepoint2name[ord('(')] = 'paren_open'
codepoint2name[ord(')')] = 'paren_close'
codepoint2name[ord('[')] = 'bracket_open'
codepoint2name[ord(']')] = 'bracket_close'
codepoint2name[ord('{')] = 'brace_open'
codepoint2name[ord('}')] = 'brace_close'
codepoint2name[ord('*')] = 'star'
codepoint2name[ord('!')] = 'bang'
codepoint2name[ord('\\')] = 'backslash'
codepoint2name[ord('+')] = 'plus'
codepoint2name[ord('$')] = 'dollar'
codepoint2name[ord('=')] = 'equals'
codepoint2name[ord('?')] = 'question'
codepoint2name[ord('@')] = 'at_sign'
codepoint2name[ord('^')] = 'caret'
codepoint2name[ord('|')] = 'pipe'
codepoint2name[ord('~')] = 'tilde'

# this must match the equivalent function in qstr.c
def compute_hash(qstr, bytes_hash):
 hash = 5381
 for b in qstr:
 hash = (hash * 33) ^ b
 # Make sure that valid hash is never zero, zero means "hash not computed"
 return (hash & ((1 << (8 * bytes_hash)) - 1)) or 1

def qstr_escape(qst):
 def esc_char(m):
 c = ord(m.group(0))
 try:
 name = codepoint2name[c]
 except KeyError:
 name = '0x%02x' % c
 return "_" + name + '_'
 return re.sub(r'[^A-Za-z0-9_]', esc_char, qst)

def parse_input_headers(infiles):
 # read the qstrs in from the input files
 qcfgs = {}
 qstrs = {}
 for infile in infiles:
 with open(infile, 'rt') as f:
 for line in f:
 line = line.strip()

 # is this a config line?
 match = re.match(r'^QCFG\((.+), (.+)\)', line)
 if match:
 value = match.group(2)
 if value[0] == '(' and value[-1] == ')':
 # strip parenthesis from config value
 value = value[1:-1]
 qcfgs[match.group(1)] = value
 continue

 # is this a QSTR line?
 match = re.match(r'^Q\((.*)\)$', line)
 if not match:
 continue

 # get the qstr value
 qstr = match.group(1)

 # special case to specify control characters
 if qstr == '\\n':
 qstr = '\n'

 # work out the corresponding qstr name
 ident = qstr_escape(qstr)

 # don't add duplicates
 if ident in qstrs:
 continue

 # add the qstr to the list, with order number to retain original order in file
 order = len(qstrs)
 # but put special method names like __add__ at the top of list, so
 # that their id's fit into a byte
 if ident == "":
 # Sort empty qstr above all still
 order = -200000
 elif ident == "__dir__":
 # Put __dir__ after empty qstr for builtin dir() to work
 order = -190000
 elif ident.startswith("__"):
 order -= 100000
 qstrs[ident] = (order, ident, qstr)

 if not qcfgs:
 sys.stderr.write("ERROR: Empty preprocessor output - check for errors above\n")
 sys.exit(1)

 return qcfgs, qstrs

def make_bytes(cfg_bytes_len, cfg_bytes_hash, qstr):
 qbytes = bytes_cons(qstr, 'utf8')
 qlen = len(qbytes)
 qhash = compute_hash(qbytes, cfg_bytes_hash)
 if all(32 <= ord(c) <= 126 and c != '\\' and c != '"' for c in qstr):
 # qstr is all printable ASCII so render it as-is (for easier debugging)
 qdata = qstr
 else:
 # qstr contains non-printable codes so render entire thing as hex pairs
 qdata = ''.join(('\\x%02x' % b) for b in qbytes)
 if qlen >= (1 << (8 * cfg_bytes_len)):
 print('qstr is too long:', qstr)
 assert False
 qlen_str = ('\\x%02x' * cfg_bytes_len) % tuple(((qlen >> (8 * i)) & 0xff) for i in range(cfg_bytes_len))
 qhash_str = ('\\x%02x' * cfg_bytes_hash) % tuple(((qhash >> (8 * i)) & 0xff) for i in range(cfg_bytes_hash))
 return '(const byte*)"%s%s" "%s"' % (qhash_str, qlen_str, qdata)

def print_qstr_data(qcfgs, qstrs):
 # get config variables
 cfg_bytes_len = int(qcfgs['BYTES_IN_LEN'])
 cfg_bytes_hash = int(qcfgs['BYTES_IN_HASH'])

 # print out the starter of the generated C header file
 print('// This file was automatically generated by makeqstrdata.py')
 print('')

 # add NULL qstr with no hash or data
 print('QDEF(MP_QSTR_NULL, (const byte*)"%s%s" "")' % ('\\x00' * cfg_bytes_hash, '\\x00' * cfg_bytes_len))

 # go through each qstr and print it out
 for order, ident, qstr in sorted(qstrs.values(), key=lambda x: x[0]):
 qbytes = make_bytes(cfg_bytes_len, cfg_bytes_hash, qstr)
 print('QDEF(MP_QSTR_%s, %s)' % (ident, qbytes))

def do_work(infiles):
 qcfgs, qstrs = parse_input_headers(infiles)
 print_qstr_data(qcfgs, qstrs)

if __name__ == "__main__":
 do_work(sys.argv[1:])