#!/usr/bin/env python3
# -*- coding: utf-8 -*-
# vim:ts=4:sw=4:softtabstop=4:smarttab:expandtab

# Copyright (c) 2014-2020 Kevin B. Hendricks and Doug Massay
# Copyright (c) 2014      John Schember
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without modification,
# are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice, this list of
# conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright notice, this list
# of conditions and the following disclaimer in the documentation and/or other materials
# provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
# EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
# SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
# TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
# OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
# WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

import sys
import os

from hrefutils import urldecodepart, buildBookPath, startingDir, longestCommonPath
from hrefutils import mime_group_map
from collections import OrderedDict

SPECIAL_HANDLING_TAGS = OrderedDict([
    ('?xml', ('xmlheader', -1)),
    ('!--', ('comment', -3)),
    ('!DOCTYPE', ('doctype', -1))
])

SPECIAL_HANDLING_TYPES = ['xmlheader', 'doctype', 'comment']

_OPF_PARENT_TAGS = ['package', 'metadata', 'dc-metadata', 'x-metadata', 'manifest', 'spine', 'tours', 'guide', 'bindings']

def build_short_name(bookpath, lvl):
    pieces = bookpath.split("/")
    if lvl == 1: return pieces.pop()
    n = len(pieces)
    if lvl >= n: return "^" + bookpath
    pieces = pieces[n - lvl:n]
    return "/".join(pieces)

class Opf_Parser(object):

    def __init__(self, opf_path, opf_bookpath, debug=False):
        self._debug = debug
        opf_path = os.fsdecode(opf_path)
        self.opfname = os.path.basename(opf_path)
        self.opf_bookpath = opf_bookpath
        self.opf_dir = startingDir(opf_bookpath)
        self.opf = None
        with open(opf_path, 'rb') as fp:
            self.opf = fp.read().decode('utf-8')
        self.opos = 0
        self.package = None
        self.metadata_attr = None
        self.metadata = []
        self.cover_id = None

        # let downstream invert any invertable dictionaries when needed
        self.manifest_id_to_href = OrderedDict()
        self.manifest_id_to_bookpath = OrderedDict()

        # create non-invertable dictionaries
        self.manifest_id_to_mime = OrderedDict()
        self.manifest_id_to_properties = OrderedDict()
        self.manifest_id_to_fallback = OrderedDict()
        self.manifest_id_to_overlay = OrderedDict()

        # spine and guide
        self.spine = []
        self.spine_ppd = None
        self.guide = []
        self.bindings = []

        # determine folder structure
        self.group_folder = OrderedDict()
        self.group_count = OrderedDict()
        self.group_folder["epub"] = ['META-INF']
        self.group_count["epub"] = [1]
        self.group_folder["opf"] = [self.opf_dir]
        self.group_count["opf"] = [1]

        # self.bookpaths = []
        # self.bookpaths.append(self.opf_bookpath)

        self._parseData()


    # OPF tag iterator
    def _opf_tag_iter(self):
        tcontent = last_tattr = None
        prefix = []
        while True:
            text, tag = self._parseopf()
            if text is None and tag is None:
                break
            if text is not None:
                tcontent = text.rstrip(" \t\v\f\r\n")
            else:  # we have a tag
                ttype, tname, tattr = self._parsetag(tag)
                if ttype == "begin":
                    tcontent = None
                    prefix.append(tname)
                    if tname in _OPF_PARENT_TAGS:
                        yield ".".join(prefix), tname, tattr, tcontent
                    else:
                        last_tattr = tattr
                else:  # single or end
                    if ttype == "end":
                        prefix.pop()
                        tattr = last_tattr
                        if tattr is None:
                            tattr = OrderedDict()
                        last_tattr = None
                    elif ttype == 'single':
                        tcontent = None
                    if ttype == 'single' or (ttype == 'end' and tname not in _OPF_PARENT_TAGS):
                        yield ".".join(prefix), tname, tattr, tcontent
                    tcontent = None

    # now parse the OPF to extract manifest, spine , and metadata
    def _parseData(self):
        cnt = 0
        for prefix, tname, tattr, tcontent in self._opf_tag_iter():
            if self._debug:
                print("   Parsing OPF: ", prefix, tname, tattr, tcontent)
            # package
            if tname == "package":
                ver = tattr.pop("version", "2.0")
                uid = tattr.pop("unique-identifier", "bookid")
                self.package = (ver, uid, tattr)
                continue
            # metadata
            if tname == "metadata":
                self.metadata_attr = tattr
                continue
            if tname in ["meta", "link"] or tname.startswith("dc:") and "metadata" in prefix:
                self.metadata.append((tname, tattr, tcontent))
                if tattr.get("name", "") == "cover":
                    self.cover_id = tattr.get("content", None)
                continue
            # manifest
            # Note: manifest hrefs when relative may not contain a fragment
            # as they must refer to and entire file
            if tname == "item" and "manifest" in prefix:
                nid = "xid%03d" % cnt
                cnt += 1
                id = tattr.pop("id", nid)
                href = tattr.pop("href", '')
                mtype = tattr.pop("media-type", '')
                if mtype == "text/html":
                    mtype = "application/xhtml+xml"
                if mtype not in mime_group_map:
                    print("****Opf_Parser Warning****: Unknown MediaType: ", mtype)
                # url decode all relative hrefs since no fragment can be present
                # meaning no ambiguity in the meaning of any # chars in path
                if href.find(':') == -1:
                    href = urldecodepart(href)
                properties = tattr.pop("properties", None)
                fallback = tattr.pop("fallback", None)
                overlay = tattr.pop("media-overlay", None)

                # external resources are now allowed in the opf under epub3
                self.manifest_id_to_href[id] = href

                bookpath = ""
                if href.find(":") == -1:
                    bookpath = buildBookPath(href, self.opf_dir)
                self.manifest_id_to_bookpath[id] = bookpath
                self.manifest_id_to_mime[id] = mtype
                # self.bookpaths.append(bookpath)
                group = mime_group_map.get(mtype, '')
                if bookpath != "" and group != "":
                    folderlst = self.group_folder.get(group, [])
                    countlst = self.group_count.get(group, [])
                    sdir = startingDir(bookpath)
                    if sdir not in folderlst:
                        folderlst.append(sdir)
                        countlst.append(1)
                    else:
                        pos = folderlst.index(sdir)
                        countlst[pos] = countlst[pos] + 1
                    self.group_folder[group] = folderlst
                    self.group_count[group] = countlst
                self.manifest_id_to_properties[id] = properties
                self.manifest_id_to_fallback[id] = fallback
                self.manifest_id_to_overlay[id] = overlay
                continue
            # spine
            if tname == "spine":
                if tattr is not None:
                    self.spine_ppd = tattr.get("page-progression-direction", None)
                continue
            if tname == "itemref" and "spine" in prefix:
                idref = tattr.pop("idref", "")
                linear = tattr.pop("linear", None)
                properties = tattr.pop("properties", None)
                self.spine.append((idref, linear, properties))
                continue
            # guide
            # Note: guide hrefs may have fragments, so leave any
            # guide hrefs in their raw urlencoded form to prevent
            # errors
            if tname == "reference" and "guide" in prefix:
                type = tattr.pop("type", '')
                title = tattr.pop("title", '')
                href = tattr.pop("href", '')
                self.guide.append((type, title, href))
                continue
            # bindings (stored but ignored for now)
            if tname in ["mediaType", "mediatype"] and "bindings" in prefix:
                mtype = tattr.pop("media-type", "")
                handler = tattr.pop("handler", "")
                self.bindings.append((mtype, handler))
                continue

        # determine unique ShortPathName for each bookpath
        # start with filename and work back up the folders
        # spn = OrderedDict()
        # dupset = set()
        # nameset = {}
        # lvl = 1
        # for bkpath in self.bookpaths:
        #     aname = build_short_name(bkpath, lvl)
        #     spn[bkpath] = aname
        #     if aname in nameset:
        #         dupset.add(aname)
        #         nameset[aname].append(bkpath)
        #     else:
        #         nameset[aname]=[bkpath]
        #
        # now work just through any to-do list of duplicates
        # until all duplicates are gone
        #
        # todolst = list(dupset)
        # while(todolst):
        #     dupset = set()
        #     lvl += 1
        #     for aname in todolst:
        #         bklst = nameset[aname]
        #         del nameset[aname]
        #         for bkpath in bklst:
        #             newname = build_short_name(bkpath, lvl)
        #             spn[bkpath] = newname
        #             if newname in nameset:
        #                 dupset.add(newname)
        #                 nameset[newname].append(bkpath)
        #             else:
        #                 nameset[newname] = [bkpath]
        #     todolst = list(dupset)

        # finally sort by number of files in dir to find default folders for each group
        dirlst = []
        use_lower_case = False
        for group in self.group_folder.keys():
            folders = self.group_folder[group]
            cnts = self.group_count[group]
            folders = [x for _, x in sorted(zip(cnts, folders), reverse=True)]
            self.group_folder[group] = folders
            if group in ["Text", "Styles", "Images", "Audio", "Fonts", "Video", "Misc"]:
                afolder = folders[0]
                if afolder.find(group.lower()) > -1:
                    use_lower_case = True
                dirlst.append(folders[0])

        # now back fill any missing values
        # commonbase will end with a /
        commonbase = longestCommonPath(dirlst)
        if commonbase == "/":
            commonbase = ""
        for group in ["Styles", "Images", "Audio", "Fonts", "Video", "Misc"]:
            folders = self.group_folder.get(group, [])
            gname = group
            if use_lower_case:
                gname = gname.lower()
            if not folders:
                folders = [commonbase + gname]
                self.group_folder[group] = folders


    # parse and return either leading text or the next tag
    def _parseopf(self):
        p = self.opos
        if p >= len(self.opf):
            return None, None
        if self.opf[p] != '<':
            res = self.opf.find('<', p)
            if res == -1 :
                res = len(self.opf)
            self.opos = res
            return self.opf[p:res], None
        # handle comment as a special case
        if self.opf[p:p + 4] == '<!--':
            te = self.opf.find('-->', p + 1)
            if te != -1:
                te = te + 2
        else:
            te = self.opf.find('>', p + 1)
            ntb = self.opf.find('<', p + 1)
            if ntb != -1 and ntb < te:
                self.opos = ntb
                return self.opf[p:ntb], None
        self.opos = te + 1
        return None, self.opf[p:te + 1]

    # parses tag to identify:  [tname, ttype, tattr]
    #    tname: tag name,    ttype: tag type ('begin', 'end' or 'single');
    #    tattr: dictionary of tag atributes
    def _parsetag(self, s):
        n = len(s)
        p = 1
        tname = None
        ttype = None
        tattr = OrderedDict()
        while p < n and s[p:p + 1] == ' ' : p += 1
        if s[p:p + 1] == '/':
            ttype = 'end'
            p += 1
            while p < n and s[p:p + 1] == ' ' : p += 1
        b = p
        # handle comment special case as there may be no spaces to
        # delimit name begin or end
        if s[b:].startswith('!--'):
            p = b + 3
            tname = '!--'
            ttype, backstep = SPECIAL_HANDLING_TAGS[tname]
            tattr['special'] = s[p:backstep].strip()
            return tname, ttype, tattr
        while p < n and s[p:p + 1] not in ('>', '/', ' ', '"', "'", "\r", "\n") : p += 1
        tname = s[b:p].lower()
        # remove redundant opf: namespace prefixes on opf tags
        if tname.startswith("opf:"):
            tname = tname[4:]
        # more special cases
        if tname == '!doctype':
            tname = '!DOCTYPE'
        if tname in SPECIAL_HANDLING_TAGS:
            ttype, backstep = SPECIAL_HANDLING_TAGS[tname]
            tattr['special'] = s[p:backstep]
        if ttype is None:
            # parse any attributes of begin or single tags
            while s.find('=', p) != -1 :
                while p < n and s[p:p + 1] == ' ' : p += 1
                b = p
                while p < n and s[p:p + 1] != '=' : p += 1
                aname = s[b:p].lower()
                aname = aname.rstrip(' ')
                p += 1
                while p < n and s[p:p + 1] == ' ' : p += 1
                if s[p:p + 1] in ('"', "'") :
                    qt = s[p:p + 1]
                    p = p + 1
                    b = p
                    while p < n and s[p:p + 1] != qt: p += 1
                    val = s[b:p]
                    p += 1
                else :
                    b = p
                    while p < n and s[p:p + 1] not in ('>', '/', ' '): p += 1
                    val = s[b:p]
                tattr[aname] = val
        if ttype is None:
            ttype = 'begin'
            if s.find('/', p) >= 0:
                ttype = 'single'
        return ttype, tname, tattr

    def handle_quoted_attribute_values(self, value):
        if '"' in value:
            value = value.replace('"', "&quot;")
        return value

    def taginfo_toxml(self, taginfo):
        res = []
        tname, tattr, tcontent = taginfo
        res.append('<' + tname)
        if tattr is not None:
            for key in tattr:
                val = self.handle_quoted_attribute_values(tattr[key])
                res.append(' ' + key + '="' + val + '"')
        if tcontent is not None:
            res.append('>' + tcontent + '</' + tname + '>\n')
        else:
            res.append('/>\n')
        return "".join(res)

    def get_epub_version(self):
        (ver, uid, tattr) = self.package
        return ver

    def get_package_tag(self):
        (ver, uid, tattr) = self.package
        packout = []
        packout.append('<package version="%s" unique-identifier="%s"' % (ver, uid))
        if tattr is not None:
            for key in tattr:
                val = self.handle_quoted_attribute_values(tattr[key])
                packout.append(' %s="%s"' % (key, val))
        packout.append(">\n")
        return "".join(packout)

    def get_metadataxml(self):
        data = []
        tattr = self.metadata_attr
        tag = "<metadata"
        if tattr is not None:
            for key in tattr:
                val = self.handle_quoted_attribute_values(tattr[key])
                tag += ' ' + key + '="' + val + '"'
        tag += '>\n'
        data.append(tag)
        for taginfo in self.metadata:
            data.append(self.taginfo_toxml(taginfo))
        data.append('</metadata>\n')
        return "".join(data)

    def get_metadata_attr(self):
        return self.metadata_attr

    # list of (tname, tattr, tcontent)
    def get_metadata(self):
        return self.metadata

    def get_manifest_id_to_href_dict(self):
        return self.manifest_id_to_href

    def get_manifest_id_to_mime_dict(self):
        return self.manifest_id_to_mime

    def get_manifest_id_to_bookpath_dict(self):
        return self.manifest_id_to_bookpath

    def get_manifest_id_to_properties_dict(self):
        return self.manifest_id_to_properties

    def get_manifest_id_to_fallback_dict(self):
        return self.manifest_id_to_fallback

    def get_manifest_id_to_overlay_dict(self):
        return self.manifest_id_to_overlay

    def get_spine_ppd(self):
        return self.spine_ppd

    # list of (idref, linear, properties)
    def get_spine(self):
        return self.spine

    # list of (type, title, href)
    def get_guide(self):
        return self.guide

    # list of (media-type, handler)
    def get_bindings(self):
        return self.bindings

    def get_group_paths(self):
        return self.group_folder



def main():
    argv = sys.argv
    if len(argv) > 1:
        filepath = argv[1]
    if filepath:
        op = Opf_Parser(filepath, 'OEBPS/content.opf')

        print('Epub Version')
        print(op.get_epub_version())
        print(' ')

        print('Package Tag')
        print(op.get_package_tag())
        print(' ')

        print('Metadata')
        print(op.get_metadataxml())
        print(' ')

        print('Guide')
        for gentry in op.get_guide():
            print('    ', gentry)
        print(' ')

        print('Spine')
        for spentry in op.get_spine():
            print('    ', spentry)
        print(' ')

        print('Dict: id to href')
        d = op.get_manifest_id_to_href_dict()
        for k, v in d.items():
            print('    ', k, ' : ', v)
        print(' ')

        print('Dict: id to mime')
        d = op.get_manifest_id_to_mime_dict()
        for k, v in d.items():
            print('    ', k, ' : ', v)
        print(' ')

        print('Dict: id to bookpath')
        d = op.get_manifest_id_to_bookpath_dict()
        for k, v in d.items():
            print('    ', k, ' : ', v)
        print(' ')

        print('Dict: id to properties')
        d = op.get_manifest_id_to_properties_dict()
        for k, v in d.items():
            print('    ', k, ' : ', v)
        print(' ')

        print('Dict: id to overlay')
        d = op.get_manifest_id_to_overlay_dict()
        for k, v in d.items():
            print('    ', k, ' : ', v)
        print(' ')

        print('Group Paths')
        d = op.get_group_paths()
        for k, v in d.items():
            print('    ', k, ' : ', v)
        print(' ')

    return 0

if __name__ == '__main__':
    sys.exit(main())
