#!/usr/bin/env python3
# encoding: utf-8
"""Classes and functions to build an AppImage."""

import os
import glob
import subprocess
import shutil
import re
import shlex
import tempfile
import urllib.request
from lxml import etree
import loaih

class Collection(list):
    """Aggregates metadata on a collection of builds."""

    def __init__(self, query, arch = ['x86', 'x86_64']):
        """Build a list of version to check/build for this round."""
        super().__init__()
        self.extend([
            Build(query, arch, version) for version in loaih.Base.collectedbuilds(query)
        ])

class Build(loaih.RemoteBuild):
    """Builds a single version."""

    LANGSTD = [ 'ar', 'de', 'en-GB', 'es', 'fr', 'it', 'ja', 'ko', 'pt',
        'pt-BR', 'ru', 'zh-CN', 'zh-TW' ]
    LANGBASIC = [ 'en-GB' ]
    ARCHSTD = [ 'x86', 'x86_64' ]

    def __init__(self, query, arch, version = None):
        super().__init__(query, version)
        self.arch = arch
        self.short_version = str.join('.', self.version.split('.')[0:2])
        self.branch_version = None
        if not '.' in self.query:
            self.branch_version = self.query
        self.url = self.basedirurl

        # Other default values
        self.language = 'basic'
        self.offline_help = False
        self.portable = False
        self.updatable = True
        self.sign = True
        self.remoterepo = False
        self.remote_host = ''
        self.remote_path = ''
        self.storage_path = '/mnt/appimage'
        self.download_path = '/var/tmp/downloads'
        self.appnamedir = ''

        # Specific build version
        self.appname = 'LibreOffice'
        self.appversion = ''
        self.appimagedir = ''
        self.appimagefilename = {}
        self.zsyncfilename = {}

        # Other variables by build
        self.languagepart = '.' + self.language
        self.helppart = ''

        # Creating a tempfile
        self.builddir = tempfile.mkdtemp()
        self.tarballs = {}
        self.built = { 'x86': False, 'x86_64': False }

        # Preparing the default for the relative path on the storage for
        # different versions.
        # The path will evaluated as part of the check() function, as it is
        # understood the storage_path can be changed before that phase.
        self.relative_path = []
        self.full_path = ''
        self.baseurl = ''

    def calculate(self):
        """Calculate exclusions and other variables."""
        # AppName
        if self.query in { 'prerelease', 'daily' }:
            self.appname = 'LibreOfficeDev'

        # Calculating languagepart
        self.languagepart = "."
        if ',' in self.language:
            self.languagepart += self.language.replace(',', '-')
        else:
            self.languagepart += self.language

        # Calculating help part
        if self.offline_help:
            self.helppart = '.help'

        # Building the required names
        for arch in Build.ARCHSTD:
            self.appimagefilename[arch] = self.__gen_appimagefilename__(self.version, arch)
            self.zsyncfilename[arch] = self.appimagefilename[arch] + '.zsync'

        # Mandate to the private function to calculate the full_path available
        # for the storage and the checks.
        self.__calculate_full_path__()


    def __gen_appimagefilename__(self, version, arch):
        """Generalize the construction of the name of the app."""
        self.appversion = version + self.languagepart + self.helppart
        return self.appname + f'-{self.appversion}-{arch}.AppImage'


    def __calculate_full_path__(self):
        """Calculate relative path of the build, based on internal other variables."""
        if len(self.relative_path) == 0:
            if self.query == 'daily':
                self.relative_path.append('daily')
            elif self.query == 'prerelease':
                self.relative_path.append('prerelease')

            # Not the same check, an additional one
            if self.portable:
                self.relative_path.append('portable')

        fullpath_arr = self.storage_path.split('/')
        # Joining relative path only if it is not null
        if len(self.relative_path) > 0:
            fullpath_arr.extend(self.relative_path)
        self.full_path = re.sub(r"/+", '/', str.join('/', fullpath_arr))


    def check(self):
        """Checking if the requested AppImage has been already built."""
        if len(self.appimagefilename) != 2:
            self.calculate()

        for arch in self.arch:

            # First, check if by metadata the repo is remote or not.
            if self.remoterepo or 'http' in self.storage_path:
                self.remoterepo = True
                # Remote storage. I have to query a remote site to know if it
                # was already built.
                name = self.appimagefilename[arch]
                if len(self.relative_path) > 0:
                    path_arr = self.relative_path.insert(0, self.storage_path)
                else:
                    path_arr = [ self.storage_path, '' ]
                path = str.join('/', path_arr)
                print(f"DEBUG - Name: {name}, URL: {path}")
                matching = []
                with urllib.request.urlopen(path) as url:
                    matching = etree.HTML(url.read()).xpath(
                        f"//a[contains(@href, '{name}')]/@href"
                    )

                if len(matching) > 0:
                    # Already built.
                    self.built[arch] = True

            else:
                # Repo is local
                print(f"Searching for {self.appimagefilename[arch]}")
                command = f"find {self.full_path} -name {self.appimagefilename[arch]}"
                res = subprocess.run(shlex.split(command),
                    capture_output=True,
                    env={ "LC_ALL": "C" },
                    text=True, encoding='utf-8', check=True)

                if "No such file or directory" in res.stderr:
                    # Folder is not existent: so the version was not built
                    # Build stays false, and we go to the next arch
                    continue

                if res.stdout and len(res.stdout.strip("\n")) > 0:
                    # All good, the command was executed fine.
                    print(f"Build for {self.version} found.")
                    self.built[arch] = True

            if self.built[arch]:
                    print(f"The requested AppImage already exists on storage for {arch}. I'll skip downloading, building and moving the results.")


    def download(self):
        """Downloads the contents of the URL as it was a folder."""
        print(f"Started downloads for {self.version}. Please wait.")
        for arch in self.arch:
            # Checking if a valid path has been provided
            if self.url[arch] == '-':
                print(f"No build has been provided for the requested AppImage for {arch}. Continue with other options.")
                # Faking already built it so to skip other checks.
                self.built[arch] = True
                continue

            if self.built[arch]:
                print(f"A build for {arch} was already found. Skipping specific packages.")
                continue

            # Identifying downloads
            contents = []
            with urllib.request.urlopen(self.url[arch]) as url:
                contents = etree.HTML(url.read()).xpath("//td/a")

            self.tarballs[arch] = [ x.text
                for x in contents
                if x.text.endswith('tar.gz') and 'deb' in x.text
            ]
            tarballs = self.tarballs[arch]

            # Create and change directory to the download location
            os.makedirs(self.download_path, exist_ok = True)
            os.chdir(self.download_path)
            for archive in tarballs:
                # If the archive is already there, do not do anything.
                if os.path.exists(archive):
                    continue

                # Download the archive
                try:
                    urllib.request.urlretrieve(self.url[arch] + archive, archive)
                except Exception as error:
                    print(f"Failed to download {archive}: {error}.")

        print(f"Finished downloads for {self.version}.")

    def build(self):
        """Building all the versions."""

        for arch in self.arch:
            if self.built[arch]:
                # Already built for arch or path not available. User has already been warned.
                continue

            # Preparation tasks
            self.appnamedir = os.path.join(self.builddir, self.appname)
            os.makedirs(self.appnamedir, exist_ok=True)
            # And then cd to the appname folder.
            os.chdir(self.appnamedir)
            # Download appimagetool from github
            appimagetoolurl = f"https://github.com/AppImage/AppImageKit/releases/download/continuous/appimagetool-{arch}.AppImage"
            urllib.request.urlretrieve(appimagetoolurl, 'appimagetool')
            os.chmod('appimagetool', 0o755)

            # Build the requested version.
            self.__unpackbuild__(arch)


    def __unpackbuild__(self, arch):
        # We start by filtering out tarballs from the list
        buildtarballs = [ self.tarballs[arch][0] ]

        # Let's process standard languages and append results to the
        # buildtarball
        if self.language == 'basic':
            if self.offline_help:
                buildtarballs.extend([ x for x in self.tarballs[arch] if 'pack_en-GB' in x ])
            else:
                buildtarballs.extend([ x for x in self.tarballs[arch] if 'langpack_en-GB' in x])
        elif self.language == 'standard':
            for lang in Build.LANGSTD:
                if self.offline_help:
                    buildtarballs.extend([ x for x in self.tarballs[arch] if ('pack_' + lang) in x ])
                else:
                    buildtarballs.extend([ x for x in self.tarballs[arch] if ('langpack_' + lang) in x ])
        elif self.language == 'full':
            if self.offline_help:
                # We need also all help. Let's replace buildtarball with the
                # whole bunch
                buildtarballs = self.tarballs[arch]
            else:
                buildtarballs.extend([ x for x in self.tarballs[arch] if 'langpack' in x ])
        else:
            # Looping for each language in self.language
            for lang in self.language.split(","):
                if self.offline_help:
                    buildtarballs.extend([ x for x in self.tarballs[arch]
                        if 'pack' + lang in x ])
                else:
                    buildtarballs.extend([ x for x in self.tarballs[arch]
                        if 'langpack' + lang in x ])

        os.chdir(self.appnamedir)

        # Unpacking the tarballs
        for archive in buildtarballs:
            subprocess.run(shlex.split(
                f"tar xzf {self.download_path}/{archive}"), check=True)

        # create appimagedir
        self.appimagedir = os.path.join(self.builddir, self.appname, self.appname + '.AppDir')
        os.makedirs(self.appimagedir, exist_ok = True)

        # At this point, let's decompress the deb packages
        subprocess.run(shlex.split(
            r"find .. -iname '*.deb' -exec dpkg -x {} . \;"
        ), cwd=self.appimagedir, check=True)

        if self.portable:
            subprocess.run(shlex.split(
                r"find . -type f -iname 'bootstraprc' " +
                r"-exec sed -i 's|^UserInstallation=.*|" +
                r"UserInstallation=\$SYSUSERCONFIG/libreoffice/%s|g' {} \+" % self.short_version
            ), cwd=self.appimagedir, check=True)

        # Changing desktop file
        subprocess.run(shlex.split(
            r"find . -iname startcenter.desktop -exec cp {} . \;"
        ), cwd=self.appimagedir, check=True)

        subprocess.run(shlex.split(
            f"sed --in-place \'s:^Name=.*$:Name={self.appname}:\' " +
            r"startcenter.desktop"
        ), cwd=self.appimagedir, check=False)

        subprocess.run(shlex.split(
            r"find . -name '*startcenter.png' -path '*hicolor*48x48*' " +
            r"-exec cp {} . \;"
        ), cwd=self.appimagedir, check=True)

        # Find the name of the binary called in the desktop file.
        binaryname = ''
        with open(
            os.path.join(self.appimagedir, 'startcenter.desktop'),
            'r', encoding="utf-8"
        ) as desktopfile:
            for line in desktopfile.readlines():
                if re.match(r'^Exec', line):
                    binaryname = line.split('=')[-1].split(' ')[0]
                    # Esci al primo match
                    break

        #binary_exec = subprocess.run(shlex.split(r"awk 'BEGIN { FS = \"=\" } /^Exec/ { print $2; exit }' startcenter.desktop | awk '{ print $1 }'"), cwd=self.appimagedir, text=True, encoding='utf-8')
        #binaryname = binary_exec.stdout.strip("\n")

        bindir=os.path.join(self.appimagedir, 'usr', 'bin')
        os.makedirs(bindir, exist_ok = True)
        subprocess.run(shlex.split(
            r"find ../../opt -iname soffice -path '*program*' " +
            r"-exec ln -sf {} ./%s \;" % binaryname
        ), cwd=bindir, check=True)

        # Download AppRun from github
        apprunurl = r"https://github.com/AppImage/AppImageKit/releases/"
        apprunurl += f"download/continuous/AppRun-{arch}"
        dest = os.path.join(self.appimagedir, 'AppRun')
        urllib.request.urlretrieve(apprunurl, dest)
        os.chmod(dest, 0o755)

        # Dealing with extra options
        buildopts = []
        if self.sign:
            buildopts.append('--sign')

        # adding zsync build if updatable
        if self.updatable:
            buildopts.append(f"-u 'zsync|{self.zsyncfilename[arch]}'")

        buildopts_str = str.join(' ', buildopts)
        # Build the number-specific build
        subprocess.run(shlex.split(
            f"{self.appnamedir}/appimagetool {buildopts_str} -v " +
            f"./{self.appname}.AppDir/"
        ), env={ "VERSION": self.appversion }, check=True)

        print(f"Built AppImage version {self.appversion}")

        # Cleanup phase, before new run.
        for deb in glob.glob(self.appnamedir + '/*.deb'):
            os.remove(deb)
        subprocess.run(shlex.split(
            r"find . -mindepth 1 -maxdepth 1 -type d -exec rm -rf {} \+"
        ), check=True)


    def checksums(self):
        """Create checksums of the built versions."""
        # Skip checksum if initally the build was already found in the storage directory
        if all(self.built[arch] for arch in self.arch):
            return

        os.chdir(self.appnamedir)
        for arch in self.arch:
            for item in [ self.appimagefilename[arch], self.zsyncfilename[arch] ]:
                # For any built arch, find out if a file exist.
                self.__create_checksum__(item)


    def __create_checksum__(self, file):
        """Internal function to create checksum file."""
        checksum = subprocess.run(
            f"md5sum {file}", shell=True, cwd=self.appnamedir,
            capture_output=True, text=True, encoding='utf-8', check=True
        )
        if checksum.stdout:
            with open(f"{file}.md5", 'w', encoding='utf-8') as csfile:
                csfile.write(checksum.stdout)

    def publish(self):
        """Moves built versions to definitive storage."""
        if all(self.built[arch] for arch in self.arch):
            # All files are already present in the full_path
            return

        os.chdir(self.appnamedir)

        # Two cases here: local and remote storage_path.
        if self.remoterepo:
            # Remote first.
            # Build destination directory
            if len(self.relative_path) > 0:
                remotepath = str.join('/', self.relative_path.insert(0, self.remote_path))
            else:
                remotepath = str.join('/', [ self.remote_path, '' ])
            try:
                subprocess.run(
                    r"rsync -rlIvz --munge-links *.AppImage* " +
                    f"{self.remote_host}:{remotepath}",
                    cwd=self.appnamedir, shell=True, check=True
                )
            finally:
                pass

        else:
            # Local
            # Forcing creation of subfolders, in case there is a new build
            os.makedirs(self.full_path, exist_ok = True)
            for file in glob.glob("*.AppImage*"):
                subprocess.run(shlex.split(
                    f"cp -f {file} {self.full_path}"
                ), check=True)


    def generalize_and_link(self, chdir = 'default'):
        """Creates the needed generalized files if needed."""
        # If called with a pointed version, no generalize and link necessary.
        if not self.branch_version:
            return

        # If a prerelease or a daily version, either.
        if self.query in { 'daily', 'prerelease' }:
            return

        if chdir == 'default':
            chdir = self.full_path

        appimagefilename = {}
        zsyncfilename = {}

        # Creating versions for short version and query text
        versions = [ self.short_version, self.branch_version ]
        for arch in Build.ARCHSTD:
            # If already built, do not do anything.
            if self.built[arch]:
                continue

            os.chdir(chdir)
            # if the appimage for the reported arch is not found, skip to next
            # arch
            if not os.path.exists(self.appimagefilename[arch]):
                continue

            # Doing it both for short_name and for branchname
            for version in versions:
                appimagefilename[arch] = self.appname + '-' + version
                appimagefilename[arch] += self.languagepart + self.helppart
                appimagefilename[arch] += f'-{arch}.AppImage'
                zsyncfilename[arch] = appimagefilename[arch] + '.zsync'

                # Create the symlink
                print(f"Creating {appimagefilename[arch]} and checksums.")
                if os.path.exists(appimagefilename[arch]):
                    os.unlink(appimagefilename[arch])
                os.symlink(self.appimagefilename[arch], appimagefilename[arch])
                # Create the checksum for the AppImage
                self.__create_checksum__(appimagefilename[arch])
                # Do not continue if no zsync file is provided.
                if not self.updatable:
                    continue

                print(f"Creating zsync file for version {version}.")
                if os.path.exists(zsyncfilename[arch]):
                    os.unlink(zsyncfilename[arch])
                shutil.copyfile(self.zsyncfilename[arch], zsyncfilename[arch])
                # Editing the zsyncfile
                subprocess.run(shlex.split(
                    r"sed --in-place 's/^Filename:.*$/Filename: " +
                    f"{appimagefilename[arch]}/' {zsyncfilename[arch]}"
                ), check=True)
                self.__create_checksum__(zsyncfilename[arch])


    def __del__(self):
        """Destructor"""
        # Cleaning up build directory
        shutil.rmtree(self.builddir)