#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import os, sys
import argparse
import codecs

from curlers import TextCurler, HtmlCurler, uncurl
from workspace import Workspace
from writer import CODECS_TO_NAME

# V a r i a b l e s

# Name invoked by
MYNAME = os.path.basename(sys.argv[0])

# Streams
input_fp = None
output_fp = None

# F u n c t i o n s

def normal():
    global input_fp, output_fp, args
    with Workspace() as ws:
        curler = TextCurler(ws)
        while True:
            line = input_fp.readline()
            ws.write(line)
            if line == "" or line == "\n":
                if args.force: uncurl(ws)
                curler.feed()
                output_fp.write(ws.getvalue())
                ws.clear()
            if line == "":
                break

def flowed():
    global input_fp, output_fp, args
    with Workspace() as ws:
        curler = TextCurler(ws)
        while True:
            line = input_fp.readline()
            if line == "":
                break
            ws.write(line)
            if args.force: uncurl(ws)
            curler.feed()
            output_fp.write(ws.getvalue())
            ws.clear()

def html():
    global input_fp, output_fp
    with Workspace(input_fp.read()) as ws:
        curler = HtmlCurler(ws)
        if args.force: uncurl(ws)
        curler.feed()
        output_fp.write(ws.getvalue())

def do_uncurl():
    global input_fp, output_fp
    with Workspace(input_fp.read()) as ws:
        uncurl(ws)
        output_fp.write(ws.getvalue())

# M a i n   P r o g r a m

# Parse arguments
parser = argparse.ArgumentParser(
    description='Make straight quotes curly.', prog=MYNAME)
group = parser.add_mutually_exclusive_group()
group.add_argument("--flowed", action="store_true", help="Input is flowed text.")
group.add_argument("--html", action="store_true", help="Input is HTML.")
group.add_argument("--uncurl", action="store_true", help="Uncurl quotes instead of curling them.")
parser.add_argument("--force", action="store_true", help="Force all quotes to straight ones first.")
parser.add_argument("--icoding", default="UTF-8", help="Input encoding (default UTF-8).")
parser.add_argument("--inplace", action="store_true", help="Edit file in-place.")
parser.add_argument("--ocoding", default="UTF-8", help="Output encoding (default UTF-8).")
parser.add_argument("input", nargs="?", help="Input file.")
parser.add_argument("output", nargs="?", help="Output file.")
try:
    args = parser.parse_args()
except SystemExit:
    sys.exit(2)

# Sanity-check codings
try:
    codec = codecs.lookup(args.icoding)
    codec = codecs.lookup(args.ocoding)
except LookupError as e:
    sys.stderr.write("{0}: {1!s}\n".format(MYNAME, e))
    sys.exit(2)
if not CODECS_TO_NAME.get(codec, "").startswith("UTF-"):
    sys.stderr.write("{0}: {1!r} output coding does not support Unicode\n".format(MYNAME, args.ocoding))
    sys.exit(1)
del codec

# Get streams
try:
    if args.input and (not args.output) and args.inplace:
        args.output = args.input
        args.input += "~"
        os.rename(args.output, args.input)
    if args.input:
        input_fp = open(args.input, "r", encoding=args.icoding)
    else:
        input_fp = open(0, "r", encoding=args.icoding)
    if args.output:
        output_fp = open(args.output, "w", encoding=args.ocoding)
    else:
        output_fp = open(1, "w", encoding=args.ocoding)
except (OSError, LookupError) as e:
    sys.stderr.write("{0}: {1!s}\n".format(MYNAME, e))
    sys.exit(1)

# Choose our mode
if args.flowed:
    flowed()
elif args.html:
    html()
elif args.uncurl:
    do_uncurl()
else:
    normal()