#!/usr/bin/env python3

import os
from http.server import *
import tempfile
import signal

r, w = os.pipe()

C_CR = 0
C_LF = 1
C_CRLF = 2

E_Raw = 0
E_Entity = 1
E_JavaScript = 2

F_Hidden = 0
F_TextArea = 1

def encode(ch, encoding):
    if ch == C_CRLF:
        return encode(C_CR, encoding) + encode(C_LF, encoding)
    if ch == C_CR:
        if encoding == E_Raw:
            return "\r"
        if encoding == E_JavaScript:
            return "\\r"
        if encoding == E_Entity:
            return "&#013;"
    if ch == C_LF:
        if encoding == E_Raw:
            return "\n"
        if encoding == E_JavaScript:
            return "\\n"
        if encoding == E_Entity:
            return "&#010;"

def get_form(ch, encoding, field):
    text = "foo" + encode(ch, encoding) + "bar"
    if encoding == E_JavaScript:
        text_initial = ""
    else:
        text_initial = text

    s = """<html>
<head>
<title>Form Test</title>
</head>
<body>
<form id="form1" name="form1" action="http://127.0.0.1:8090/">
"""
    if field == F_Hidden:
        s += '<input type="hidden" id="field1" name="field1" value="' + text_initial + '">'
    elif field == F_TextArea:
        s += '<textarea id="field1" name="field1">' + text_initial + '</textarea>'
    s += "\n</form>"
    if encoding == E_JavaScript:
        s += """
<script>
document.form1.field1.value = '%s';
</script>""" % (text)

    s += "</body></html>"
    return s

class forwarder(BaseHTTPRequestHandler):
    def do_GET(self):
        w.write(self.path + "\n")
        w.flush()
        self.send_response(200)
        self.send_header("Content-Type", "text/plain")
        self.end_headers()
        self.wfile.write(b"Dummy response")

def runtest(r, *args):
    form = get_form(*args)

    tmpfile, tmpname = tempfile.mkstemp(".html")
    tmpfile = os.fdopen(tmpfile, 'w')
    tmpfile.write(form)
    tmpfile.close()

    linkspid = os.spawnlp(os.P_NOWAIT, 'elinks', 'elinks',
        '-config-dir', os.getcwd(),
        '-config-file', 'crlf.conf',
        '-no-connect', '1',
        '-auto-submit', '1',
        tmpname)
    path = r.readline()
    os.kill(linkspid, signal.SIGINT)
    os.waitpid(linkspid, 0)

    os.unlink(tmpname)

    return path

pid = os.fork()

if pid:
    os.close(w)
    r = os.fdopen(r)

    paths = []

    for c in [C_CR, C_LF, C_CRLF]:
        for e in [E_Raw, E_Entity, E_JavaScript]:
            for f in [F_Hidden, F_TextArea]:
                paths.append(("%d %d %d " % (c, e, f)) + runtest(r, c, e, f))

    for path in paths:
        print(path, end=' ')

    os.kill(pid, signal.SIGTERM)
    os.waitpid(pid, 0)
else:
    os.close(r)
    w = os.fdopen(w, 'w')
    server_address = ('127.0.0.1', 8090)
    httpd = HTTPServer(server_address, forwarder)
    httpd.serve_forever()