#!/usr/bin/env python3

class MMGenObject(object):
	'placeholder - overridden when testing'
	def immutable_attr_init_check(self): pass

import os
if os.getenv('MMGEN_DEBUG') or os.getenv('MMGEN_TEST_SUITE') or os.getenv('MMGEN_EXEC_WRAPPER'):

	import sys,re,traceback,json,pprint
	from decimal import Decimal
	from difflib import unified_diff,ndiff

	def pmsg(*args,out=sys.stderr):
		d = args if len(args) > 1 else '' if not args else args[0]
		out.write(pprint.PrettyPrinter(indent=4).pformat(d) + '\n')
	def pdie(*args,exit_val=1,out=sys.stderr):
		pmsg(*args,out=out)
		sys.exit(exit_val)
	def pexit(*args,out=sys.stderr):
		pdie(*args,exit_val=0,out=out)

	def Pmsg(*args):
		pmsg(*args,out=sys.stdout)
	def Pdie(*args):
		pdie(*args,out=sys.stdout)
	def Pexit(*args):
		pexit(*args,out=sys.stdout)

	def print_stack_trace(message=None,fh=[],nl='\n',sep='\n  '):

		if not fh:
			fh.append(open(f'devtools.trace.{os.getpid()}','w'))
			nl = ''

		tb = [t for t in traceback.extract_stack() if t.filename[:1] != '<'][:-1]
		fs = '{}:{}: in {}:\n    {}'
		out = [
			fs.format(
				re.sub(r'^\./','',os.path.relpath(t.filename)),
				t.lineno,
				(t.name+'()' if t.name[-1] != '>' else t.name),
				t.line or '(none)')
			for t in tb ]

		text = f'{nl}STACK TRACE {message or "[unnamed]"}:{sep}{sep.join(out)}\n'
		sys.stderr.write(text)
		fh[0].write(text)

	class MMGenObject(object):

		def print_stack_trace(self,*args,**kwargs):
			print_stack_trace(*args,**kwargs)

		# Pretty-print any object subclassed from MMGenObject, recursing into sub-objects - WIP
		def pmsg(self,*args):
			print(args[0] if len(args) == 1 else args if args else self.pfmt())

		def pdie(self,*args):
			self.pmsg(*args)
			sys.exit(1)

		def pexit(self,*args):
			self.pmsg(*args)
			sys.exit(0)

		def pfmt(self,lvl=0,id_list=[]):
			scalars = (str,int,float,Decimal)
			def do_list(out,e,lvl=0,is_dict=False):
				out.append('\n')
				for i in e:
					el = i if not is_dict else e[i]
					if is_dict:
						out.append('{s}{:<{l}}'.format(i,s=' '*(4*lvl+8),l=10,l2=8*(lvl+1)+8))
					if hasattr(el,'pfmt'):
						out.append('{:>{l}}{}'.format(
							'',
							el.pfmt( lvl=lvl+1, id_list=id_list+[id(self)] ),
							l = (lvl+1)*8 ))
					elif isinstance(el,scalars):
						if isList(e):
							out.append( '{:>{l}}{!r:16}\n'.format( '', el, l=lvl*8 ))
						else:
							out.append(f' {el!r}')
					elif isList(el) or isDict(el):
						indent = 1 if is_dict else lvl*8+4
						out.append('{:>{l}}{:16}'.format( '', f'<{type(el).__name__}>', l=indent ))
						if isList(el) and isinstance(el[0],scalars):
							out.append('\n')
						do_list(out,el,lvl=lvl+1,is_dict=isDict(el))
					else:
						out.append('{:>{l}}{:16} {!r}\n'.format( '', f'<{type(el).__name__}>', el, l=(lvl*8)+8 ))
					out.append('\n')

				if not e:
					out.append(f'{e!r}\n')

			def isDict(obj):
				return isinstance(obj,dict)
			def isList(obj):
				return isinstance(obj,list)
			def isScalar(obj):
				return isinstance(obj,scalars)

			out = [f'<{type(self).__name__}>{" "+repr(self) if isScalar(self) else ""}\n']

			if id(self) in id_list:
				return out[-1].rstrip() + ' [RECURSION]\n'
			if isList(self) or isDict(self):
				do_list(out,self,lvl=lvl,is_dict=isDict(self))

			for k in self.__dict__:
				e = getattr(self,k)
				if isList(e) or isDict(e):
					out.append('{:>{l}}{:<10} {:16}'.format( '', k, f'<{type(e).__name__}>', l=(lvl*8)+4 ))
					do_list(out,e,lvl=lvl,is_dict=isDict(e))
				elif hasattr(e,'pfmt') and type(e) != type:
					out.append('{:>{l}}{:10} {}'.format(
						'',
						k,
						e.pfmt( lvl=lvl+1, id_list=id_list+[id(self)] ),
						l = (lvl*8)+4 ))
				else:
					out.append('{:>{l}}{:<10} {:16} {}\n'.format(
						'',
						k,
						f'<{type(e).__name__}>',
						repr(e),
						l=(lvl*8)+4 ))

			import re
			return re.sub('\n+','\n',''.join(out))

		# Check that all immutables have been initialized.  Expensive, so do only when testing.
		def immutable_attr_init_check(self):
			from .globalvars import g
			if g.test_suite:
				from .util import die
				cls = type(self)
				for attrname in sorted({a for a in self.valid_attrs if a[0] != '_'}):
					for o in (cls,cls.__bases__[0]): # assume there's only one base class
						if attrname in o.__dict__:
							attr = o.__dict__[attrname]
							break
					else:
						die(4,f'unable to find descriptor {cls.__name__}.{attrname}')
					if type(attr).__name__ == 'ImmutableAttr':
						if attrname not in self.__dict__:
							die(4,
						f'attribute {attrname!r} of {cls.__name__} has not been initialized in constructor!')

	def print_diff(a,b,from_file='',to_file='',from_json=True):
		if from_json:
			a = json.dumps(json.loads(a),indent=4).split('\n') if a else []
			b = json.dumps(json.loads(b),indent=4).split('\n') if b else []
		else:
			a = a.split('\n')
			b = b.split('\n')
		sys.stderr.write('  DIFF:\n    {}\n'.format(
			'\n    '.join(unified_diff(a,b,from_file,to_file)) ))

	def get_ndiff(a,b):
		a = a.split('\n')
		b = b.split('\n')
		return list(ndiff(a,b))