import re, cStringIO, traceback
import urwid
from PIL import Image
from PIL.ExifTags import TAGS
import lxml.html, lxml.etree
import common
from .. import utils, encoding, flow
from ..contrib import jsbeautifier, html2text

VIEW_CUTOFF = 1024*50

VIEW_AUTO = 0
VIEW_JSON = 1
VIEW_XML = 2
VIEW_URLENCODED = 3
VIEW_MULTIPART = 4
VIEW_JAVASCRIPT = 5
VIEW_IMAGE = 6
VIEW_RAW = 7
VIEW_HEX = 8
VIEW_HTML = 9
VIEW_OUTLINE = 10
VIEW_AMF = 11

VIEW_NAMES = {
    VIEW_AUTO: "Auto",
    VIEW_JSON: "JSON",
    VIEW_XML: "XML",
    VIEW_URLENCODED: "URL-encoded",
    VIEW_MULTIPART: "Multipart Form",
    VIEW_JAVASCRIPT: "JavaScript",
    VIEW_IMAGE: "Image",
    VIEW_RAW: "Raw",
    VIEW_HEX: "Hex",
    VIEW_HTML: "HTML",
    VIEW_OUTLINE: "HTML Outline",
}


VIEW_PROMPT = [
    ("auto detect", "a"),
    ("hex", "e"),
    ("html", "h"),
    ("image", "i"),
    ("javascript", "j"),
    ("html outline", "o"),
    ("json", "s"),
    ("raw", "r"),
    ("multipart", "m"),
    ("urlencoded", "u"),
    ("xml", "x"),
]

VIEW_SHORTCUTS = {
    "a": VIEW_AUTO,
    "x": VIEW_XML,
    "h": VIEW_HTML,
    "i": VIEW_IMAGE,
    "j": VIEW_JAVASCRIPT,
    "s": VIEW_JSON,
    "u": VIEW_URLENCODED,
    "m": VIEW_MULTIPART,
    "o": VIEW_OUTLINE,
    "r": VIEW_RAW,
    "e": VIEW_HEX,
}

CONTENT_TYPES_MAP = {
    "text/html": VIEW_HTML,
    "application/json": VIEW_JSON,
    "text/xml": VIEW_XML,
    "multipart/form-data": VIEW_MULTIPART,
    "application/x-www-form-urlencoded": VIEW_URLENCODED,
    "application/x-javascript": VIEW_JAVASCRIPT,
    "application/javascript": VIEW_JAVASCRIPT,
    "text/javascript": VIEW_JAVASCRIPT,
    "image/png": VIEW_IMAGE,
    "image/jpeg": VIEW_IMAGE,
    "image/gif": VIEW_IMAGE,
    "image/vnd.microsoft.icon": VIEW_IMAGE,
    "image/x-icon": VIEW_IMAGE,
}

def trailer(clen, txt, limit):
    rem = clen - limit
    if rem > 0:
        txt.append(urwid.Text(""))
        txt.append(
            urwid.Text(
                [
                    ("highlight", "... %s of data not shown. Press "%utils.pretty_size(rem)),
                    ("key", "f"),
                    ("highlight", " to load all data.")
                ]
            )
        )


def _view_text(content, total, limit):
    """
        Generates a body for a chunk of text.
    """
    txt = []
    for i in utils.cleanBin(content).splitlines():
        txt.append(
            urwid.Text(("text", i), wrap="any")
        )
    trailer(total, txt, limit)
    return txt


def view_raw(hdrs, content, limit):
    txt = _view_text(content[:limit], len(content), limit)
    return "Raw", txt


def view_hex(hdrs, content, limit):
    txt = []
    for offset, hexa, s in utils.hexdump(content[:limit]):
        txt.append(urwid.Text([
            ("offset", offset),
            " ",
            ("text", hexa),
            "   ",
            ("text", s),
        ]))
    trailer(len(content), txt, limit)
    return "Hex", txt


def view_xml(hdrs, content, limit):
    parser = lxml.etree.XMLParser(remove_blank_text=True, resolve_entities=False, strip_cdata=False, recover=False)
    try:
        document = lxml.etree.fromstring(content, parser)
    except lxml.etree.XMLSyntaxError:
        return None
    docinfo = document.getroottree().docinfo

    prev = []
    p = document.getroottree().getroot().getprevious()
    while p is not None:
        prev.insert(
            0,
            lxml.etree.tostring(p)
        )
        p = p.getprevious()
    doctype=docinfo.doctype
    if prev:
        doctype += "\n".join(prev).strip()
    doctype = doctype.strip()

    s = lxml.etree.tostring(
            document,
            pretty_print=True,
            xml_declaration=True,
            doctype=doctype or None,
            encoding = docinfo.encoding
        )

    txt = []
    for i in s[:limit].strip().split("\n"):
        txt.append(
            urwid.Text(("text", i)),
        )
    trailer(len(content), txt, limit)
    return "XML-like data", txt


def view_html(hdrs, content, limit):
    if utils.isXML(content):
        parser = lxml.etree.HTMLParser(strip_cdata=True, remove_blank_text=True)
        d = lxml.html.fromstring(content, parser=parser)
        docinfo = d.getroottree().docinfo
        s = lxml.etree.tostring(d, pretty_print=True, doctype=docinfo.doctype)
        return "HTML", _view_text(s[:limit], len(s), limit)


def view_outline(hdrs, content, limit):
    content = content.decode("utf-8")
    h = html2text.HTML2Text(baseurl="")
    h.ignore_images = True
    h.body_width = 0
    content = h.handle(content)
    txt = _view_text(content[:limit], len(content), limit)
    return "HTML Outline", txt


def view_json(hdrs, content, limit):
    lines = utils.pretty_json(content)
    if lines:
        txt = []
        sofar = 0
        for i in lines:
            sofar += len(i)
            txt.append(
                urwid.Text(("text", i)),
            )
            if sofar > limit:
                break
        trailer(sum(len(i) for i in lines), txt, limit)
        return "JSON", txt


def view_multipart(hdrs, content, limit):
    v = hdrs.get("content-type")
    if v:
        v = utils.parse_content_type(v[0])
        if not v:
            return
        boundary = v[2].get("boundary")
        if not boundary:
            return

        rx = re.compile(r'\bname="([^"]+)"')
        keys = []
        vals = []

        for i in content.split("--" + boundary):
            parts = i.splitlines()
            if len(parts) > 1 and parts[0][0:2] != "--":
                match = rx.search(parts[1])
                if match:
                    keys.append(match.group(1) + ":")
                    vals.append(utils.cleanBin(
                        "\n".join(parts[3+parts[2:].index(""):])
                    ))
        r = [
            urwid.Text(("highlight", "Form data:\n")),
        ]
        r.extend(common.format_keyvals(
            zip(keys, vals),
            key = "header",
            val = "text"
        ))
        return "Multipart form", r


def view_urlencoded(hdrs, content, limit):
    lines = utils.urldecode(content)
    if lines:
        body = common.format_keyvals(
                    [(k+":", v) for (k, v) in lines],
                    key = "header",
                    val = "text"
               )
        return "URLEncoded form", body


def view_javascript(hdrs, content, limit):
    opts = jsbeautifier.default_options()
    opts.indent_size = 2
    res = jsbeautifier.beautify(content[:limit], opts)
    return "JavaScript", _view_text(res, len(content), limit)


def view_image(hdrs, content, limit):
    try:
        img = Image.open(cStringIO.StringIO(content))
    except IOError:
        return None
    parts = [
        ("Format", str(img.format_description)),
        ("Size", "%s x %s px"%img.size),
        ("Mode", str(img.mode)),
    ]
    for i in sorted(img.info.keys()):
        if i != "exif":
            parts.append(
                (str(i), str(img.info[i]))
            )
    if hasattr(img, "_getexif"):
        ex = img._getexif()
        if ex:
            for i in sorted(ex.keys()):
                tag = TAGS.get(i, i)
                parts.append(
                    (str(tag), str(ex[i]))
                )
    clean = []
    for i in parts:
        clean.append([utils.cleanBin(i[0]), utils.cleanBin(i[1])])
    fmt = common.format_keyvals(
            clean,
            key = "header",
            val = "text"
        )
    return "%s image"%img.format, fmt

def view_amf(hdrs, content, limit):
    s = utils.pretty_amf(content)
    if s:
        return "AMF", _view_text(s[:limit], len(s), limit)

PRETTY_FUNCTION_MAP = {
    VIEW_XML: view_xml,
    VIEW_HTML: view_html,
    VIEW_JSON: view_json,
    VIEW_URLENCODED: view_urlencoded,
    VIEW_MULTIPART: view_multipart,
    VIEW_JAVASCRIPT: view_javascript,
    VIEW_IMAGE: view_image,
    VIEW_HEX: view_hex,
    VIEW_RAW: view_raw,
    VIEW_OUTLINE: view_outline,
}

def get_view_func(viewmode, hdrs, content):
    """
        Returns a function object.
    """
    if viewmode == VIEW_AUTO:
        ctype = hdrs.get("content-type")
        if ctype:
            ctype = ctype[0]
        ct = utils.parse_content_type(ctype) if ctype else None
        if ct:
            viewmode = CONTENT_TYPES_MAP.get("%s/%s"%(ct[0], ct[1]))
        if not viewmode and utils.isXML(content):
            viewmode = VIEW_XML
    return PRETTY_FUNCTION_MAP.get(viewmode, view_raw)


def get_content_view(viewmode, hdrItems, content, limit):
    """
        Returns a (msg, body) tuple.
    """
    msg = []

    hdrs = flow.ODictCaseless([list(i) for i in hdrItems])

    enc = hdrs.get("content-encoding")
    if enc and enc[0] != "identity":
        decoded = encoding.decode(enc[0], content)
        if decoded:
            content = decoded
            msg.append("[decoded %s]"%enc[0])
    func = get_view_func(viewmode, hdrs, content)
    try:
        ret = func(hdrs, content, limit)
    # Third-party viewers can fail in unexpected ways...
    except Exception, e:
        s = traceback.format_exc()
        return "", _view_text(s, len(s), len(s))
        ret = None
    if not ret:
        viewmode = VIEW_RAW
        ret = view_raw(hdrs, content, limit)
        msg.append("Couldn't parse: falling back to Raw")
    else:
        msg.append(ret[0])
    return " ".join(msg), ret[1]


#
# Enable optional decoding methods at runtime
#

# AMF decoding requires pyamf
try:
    import pyamf

    VIEW_SHORTCUTS["f"] = VIEW_AMF
    VIEW_PROMPT.append(("amf", "f"))
    VIEW_NAMES[VIEW_AMF] = "AMF"
    CONTENT_TYPES_MAP["application/x-amf"] = VIEW_AMF
    PRETTY_FUNCTION_MAP[VIEW_AMF] = view_amf
except ImportError:
    pass