import logging
import re
from subprocess import check_output

from django.conf import settings
from django.db import models
from django.urls import reverse
from django.utils.dateparse import parse_datetime
from django.utils.safestring import mark_safe

import git
import requests
from autoslug import AutoSlugField
from ndh.models import Links, NamedModel, TimeStampedModel
from ndh.utils import enum_to_choices

from .utils import SOURCES, TARGETS, slugify_with_dots

logger = logging.getLogger('rainboard.models')

MAIN_BRANCHES = ['master', 'devel']
RPKG_URL = 'http://robotpkg.openrobots.org'
RPKG_LICENSES = {'gnu-lgpl-v3': 'LGPL-3.0', 'gnu-lgpl-v2': 'LGPL-2.0', 'mit': 'MIT', 'gnu-gpl-v3': 'GPL-3.0',
                 '2-clause-bsd': 'BSD-2-Clause'}
RPKG_FIELDS = ['PKGBASE', 'PKGVERSION', 'MASTER_SITES', 'MASTER_REPOSITORY', 'MAINTAINER', 'COMMENT', 'HOMEPAGE']
CMAKE_FIELDS = {'NAME': 'name', 'DESCRIPTION': 'description', 'URL': 'homepage', 'VERSION': 'version'}
TRAVIS_STATE = {'created': None, 'passed': True, 'started': None, 'failed': False, 'errored': False, 'canceled': False}
GITLAB_STATUS = {'failed': False, 'success': True, 'pending': None, 'skipped': None, 'canceled': None}


class Article(NamedModel):
    authors = models.ManyToManyField(settings.AUTH_USER_MODEL)
    year = models.PositiveSmallIntegerField()
    url = models.URLField(max_length=200)
    pdf = models.URLField(max_length=200)


class Namespace(NamedModel):
    group = models.BooleanField(default=False)


class License(models.Model):
    name = models.CharField(max_length=200)
    spdx_id = models.CharField(max_length=50, unique=True)
    url = models.URLField(max_length=200)

    def __str__(self):
        return self.spdx_id or self.name


class Forge(Links, NamedModel):
    source = models.PositiveSmallIntegerField(choices=enum_to_choices(SOURCES))
    url = models.URLField(max_length=200)
    token = models.CharField(max_length=50, blank=True, null=True)
    verify = models.BooleanField(default=True)

    def get_absolute_url(self):
        return self.url

    def api_data(self, url=''):
        logger.info(f'requesting api {self}{url}')
        req = requests.get(self.api_url() + url, verify=self.verify, headers=self.headers())
        return req.json() if req.status_code == 200 else []

    def headers(self):
        return {
            SOURCES.github: {'Authorization': f'token {self.token}', 'Accept':
                             'application/vnd.github.drax-preview+json'},
            SOURCES.gitlab: {'Private-Token': self.token},
            SOURCES.redmine: {'X-Redmine-API-Key': self.token},
            SOURCES.travis: {'Authorization': f'token {self.token}',
                             'TRAVIS-API-Version': '3'},
        }[self.source]

    def api_url(self):
        return {
            SOURCES.github: 'https://api.github.com',
            SOURCES.gitlab: f'{self.url}/api/v4',
            SOURCES.redmine: self.url,
            SOURCES.travis: 'https://api.travis-ci.org',
        }[self.source]

    def get_projects(self):
        return getattr(self, f'get_projects_{self.get_source_display()}')()

    def get_namespaces_github(self):
        for namespace in Namespace.objects.filter(group=True):
            for data in self.api_data(f'/orgs/{namespace.slug}/members'):
                Namespace.objects.get_or_create(slug=data['login'],
                                                defaults={'name': data['login'], 'group': False})

    def get_projects_github(self):
        def update_github(namespace, data):
            project, _ = Project.objects.get_or_create(name=data['name'], defaults={
                'homepage': data['homepage'], 'main_namespace': namespace, 'main_forge': self})
            repo, _ = Repo.objects.get_or_create(forge=self, namespace=namespace, project=project,
                                                 defaults={'repo_id': data['id'], 'name': data['name']})
            repo.homepage = data['homepage']
            repo.url = data['html_url']
            repo.repo_id = data['id']
            repo.default_branch = data['default_branch']
            repo.open_issues = data['open_issues']

            repo_data = repo.api_data()
            if repo_data and 'license' in repo_data and repo_data['license']:
                if 'spdx_id' in repo_data['license'] and repo_data['license']['spdx_id']:
                    license = License.objects.get(spdx_id=repo_data['license']['spdx_id'])
                    repo.license = license
                    if not project.license:
                        project.license = license
            repo.open_pr = len(repo.api_data('/pulls'))
            repo.save()
            project.save()

        self.get_namespaces_github()
        for org in Namespace.objects.filter(group=True):
            for data in self.api_data(f'/orgs/{org.slug}/repos'):
                update_github(org, data)
        for user in Namespace.objects.filter(group=False):
            for data in self.api_data(f'/users/{user.slug}/repos'):
                if not Project.objects.filter(name=data['name']).exists():
                    continue
                update_github(user, data)

    def get_namespaces_gitlab(self):
        for data in self.api_data('/namespaces'):
            Namespace.objects.get_or_create(slug=data['path'],
                                            defaults={'name': data['name'], 'group': data['kind'] == 'group'})

    def get_projects_gitlab(self):
        def update_gitlab(data):
            project, created = Project.objects.get_or_create(name=data['name'], defaults={'main_forge': self})
            namespace, _ = Namespace.objects.get_or_create(name=data['namespace']['name'])
            repo, _ = Repo.objects.get_or_create(forge=self, namespace=namespace, project=project,
                                                 defaults={'repo_id': data['id'], 'name': data['name'],
                                                           'url': data['web_url']})
            if 'forked_from_project' in data:
                repo.forked_from = data['forked_from_project']['id']
                repo.save()
            elif created or project.main_namespace is None:
                project.main_namespace = namespace
                project.save()

        self.get_namespaces_gitlab()

        for data in self.api_data('/projects'):
            update_gitlab(data)

        for orphan in Project.objects.filter(main_namespace=None):
            repo = orphan.repo_set.filter(forge__source=SOURCES.gitlab).first()
            update_gitlab(self.api_data(f'/projects/{repo.forked_from}'))

    def get_projects_redmine(self):
        pass  # TODO


def get_default_forge(project):
    for forge in Forge.objects.order_by('source'):
        if project.repo_set.filter(forge=forge).exists():
            logger.info(f'default forge for {project} set to {forge}')
            project.main_forge = forge
            project.save()
            return forge
    else:
        logger.error(f'NO DEFAULT FORGE for {project}')


class Project(Links, NamedModel, TimeStampedModel):
    private = models.BooleanField(default=False)
    main_namespace = models.ForeignKey(Namespace, on_delete=models.SET_NULL, null=True, blank=True)
    main_forge = models.ForeignKey(Forge, on_delete=models.SET_NULL, null=True, blank=True)
    license = models.ForeignKey(License, on_delete=models.SET_NULL, blank=True, null=True)
    homepage = models.URLField(max_length=200, blank=True, null=True)
    articles = models.ManyToManyField(Article)
    description = models.TextField()
    version = models.CharField(max_length=20, blank=True, null=True)
    updated = models.DateTimeField(blank=True, null=True)
    # TODO: release github ↔ robotpkg

    def get_absolute_url(self):
        return reverse('rainboard:project', kwargs={'slug': self.slug})

    def git_path(self):
        logger.info(f'git_path for {self} in {self.main_namespace}')
        return settings.RAINBOARD_GITS / self.main_namespace.slug / self.slug

    def git(self):
        path = self.git_path()
        if not path.exists():
            logger.info(f'Creating repo for {self.main_namespace.slug}/{self.slug}')
            return git.Repo.init(path)
        return git.Repo(str(path / '.git'))

    def main_repo(self):
        forge = self.main_forge if self.main_forge else get_default_forge(self)
        repo, created = Repo.objects.get_or_create(forge=forge, namespace=self.main_namespace, project=self,
                                                   defaults={'name': self.name, 'default_branch': 'master',
                                                             'repo_id': 0})
        if created:
            repo.api_update()
        return repo

    def update_branches(self, main=True):
        branches = [b[2:] for b in self.git().git.branch('-a', '--no-color').split('\n')]
        if main:
            branches = [b for b in branches if b.endswith('master') or b.endswith('devel')]
        for branch in branches:
            logger.info(f'update branch {branch}')
            if branch in MAIN_BRANCHES:
                instance, created = Branch.objects.get_or_create(name=branch, project=self)
            else:
                if branch.startswith('remotes/'):
                    branch = branch[8:]
                forge, namespace, name = branch.split('/', maxsplit=2)
                namespace, _ = Namespace.objects.get_or_creat(slug=namespace)
                repo, created = Repo.objects.get_or_create(forge__slug=forge, namespace=namespace, project=self,
                                                           defaults={'name': self.name, 'default_branch': 'master',
                                                                     'repo_id': 0})
                if created:
                    repo.api_update()
                instance, created = Branch.objects.get_or_create(name=branch, project=self, repo=repo)
            if created:
                instance.update()

    def main_branch(self):
        return 'devel' if 'devel' in self.git().heads else 'master'

    def cmake(self):
        filename = self.git_path() / 'CMakeLists.txt'
        if not filename.exists():
            return
        with filename.open() as f:
            content = f.read()
        for key, value in CMAKE_FIELDS.items():
            search = re.search(f'set\s*\(\s*project_{key}\s+([^)]+)*\)', content, re.I)
            if search:
                self.__dict__[value] = search.groups()[0].strip(''' \r\n\t'"''')
                self.save()

    def repos(self):
        return self.repo_set.count()

    def rpkgs(self):
        return self.robotpkg_set.count()

    def update_tags(self):
        for tag in self.git().tags:
            Tag.objects.get_or_create(name=str(tag), project=self)

    def update(self):
        self.update_tags()
        self.version = self.tag_set.filter(name__startswith='v').last().name
        robotpkg = self.robotpkg_set.order_by('-updated').first()
        branch = self.branch_set.order_by('-updated').first()
        if branch is not None or robotpkg is not None:
            if robotpkg is None:
                self.updated = branch.updated
            elif branch is None:
                self.updated = robotpkg.updated
            else:
                self.updated = max(branch.updated, robotpkg.updated)
        self.save()


class Repo(TimeStampedModel):
    name = models.CharField(max_length=200)
    slug = AutoSlugField(populate_from='name', slugify=slugify_with_dots)
    forge = models.ForeignKey(Forge, on_delete=models.CASCADE)
    namespace = models.ForeignKey(Namespace, on_delete=models.CASCADE)
    project = models.ForeignKey(Project, on_delete=models.CASCADE)
    license = models.ForeignKey(License, on_delete=models.SET_NULL, blank=True, null=True)
    homepage = models.URLField(max_length=200, blank=True, null=True)
    url = models.URLField(max_length=200, blank=True, null=True)
    default_branch = models.CharField(max_length=50)
    open_issues = models.PositiveSmallIntegerField(blank=True, null=True)
    open_pr = models.PositiveSmallIntegerField(blank=True, null=True)
    repo_id = models.PositiveIntegerField()
    forked_from = models.PositiveIntegerField(blank=True, null=True)
    clone_url = models.URLField(max_length=200, blank=True, null=True)
    travis_id = models.PositiveIntegerField(blank=True, null=True)
    # TODO gitlab:
    # description = models.TextField()
    # created_at = models.DateTimeField()
    # last_activity_at = models.DateTimeField()

    def __str__(self):
        return self.name

    def api_url(self):
        return {
            SOURCES.github: f'{self.forge.api_url()}/repos/{self.namespace.slug}/{self.slug}',
            SOURCES.redmine: f'{self.forge.api_url()}/projects/{self.repo_id}.json',
            SOURCES.gitlab: f'{self.forge.api_url()}/projects/{self.repo_id}',
        }[self.forge.source]

    def api_data(self, url=''):
        logger.info(f'requesting api {self.forge} {self.namespace} {self} {url}')
        req = requests.get(self.api_url() + url, verify=self.forge.verify, headers=self.forge.headers())
        return req.json() if req.status_code == 200 else []

    def api_update(self):
        data = self.api_data()
        if data:
            return getattr(self, f'api_update_{self.forge.get_source_display()}')(data)

    def api_update_gitlab(self, data):
        # TODO Missing: license, homepage, open_pr
        self.name = data['name']
        self.slug = data['path']
        self.url = data['web_url']
        self.open_issues = data['open_issues_count']
        self.default_branch = data['default_branch']
        if 'forked_from_project' in data:
            self.forked_from = data['forked_from_project']['id']
        self.clone_url = data['http_url_to_repo']
        self.save()

    def api_update_github(self, data):
        # TODO Missing: open_pr
        self.name = data['name']
        if data['license'] is not None:
            self.license = License.objects.filter(spdx_id=data['license']['spdx_id']).first()
        self.homepage = data['homepage']
        self.url = data['url']
        self.default_branch = data['default_branch']
        self.open_issues = data['open_issues_count']
        self.repo_id = data['id']
        if 'source' in data:
            self.forked_from = data['source']['id']
        self.clone_url = data['clone_url']
        self.save()

    def get_clone_url(self):
        if self.forge.source == SOURCES.gitlab:
            return self.clone_url.replace('://', f'://gitlab-ci-token:{self.forge.token}@')
        return self.clone_url

    def git_remote(self):
        return f'{self.forge.slug}/{self.namespace.slug}'

    def git(self):
        git_repo = self.project.git()
        remote = self.git_remote()
        try:
            return git_repo.remote(remote)
        except ValueError:
            logger.info(f'Creating remote {remote}')
            return git_repo.create_remote(remote, self.get_clone_url())

    def main_branch(self):
        return self.project.branch_set.get(name=f'{self.git_remote()}/{self.default_branch}')

    def ahead(self):
        return self.main_branch().ahead

    def behind(self):
        return self.main_branch().behind

    def get_builds(self):
        return getattr(self, f'get_builds_{self.forge.get_source_display()}')()

    def get_builds_gitlab(self):
        for pipeline in self.api_data('/pipelines'):
            pid, ref = pipeline['id'], pipeline['ref']
            if self.project.tag_set.filter(name=ref).exists():
                continue
            data = self.api_data(f'/pipelines/{pid}')
            branch_name = f'{self.forge.slug}/{self.namespace.slug}/{ref}'
            branch, created = Branch.objects.get_or_create(name=branch_name, project=self.project, repo=self)
            if created:
                branch.update()
            CIBuild.objects.get_or_create(repo=self, build_id=pid, defaults={
                'passed': GITLAB_STATUS[pipeline['status']],
                'started': parse_datetime(data['created_at']),
                'branch': branch,
            })

    def get_builds_github(self):
        if self.travis_id is not None:
            travis = Forge.objects.get(source=SOURCES.travis)
            for build in travis.api_data(f'/repo/{self.travis_id}/builds')['builds']:
                if self.project.tag_set.filter(name=build['branch']['name']).exists():
                    continue
                branch_name = f'{self.forge.slug}/{self.namespace.slug}/{build["branch"]["name"]}'
                branch, created = Branch.objects.get_or_create(name=branch_name, project=self.project, repo=self)
                if created:
                    try:
                        branch.update()
                    except git.exc.GitCommandError:
                        # Some guys might delete some branches…
                        # eg. https://travis-ci.org/stack-of-tasks/dynamic-graph/builds/246184885
                        logger.error(f' DELETED BRANCH for {self.project}: {branch_name}')
                        branch.delete()
                        continue
                started = build['started_at'] if build['started_at'] is not None else build['finished_at']
                CIBuild.objects.get_or_create(repo=self, build_id=build['id'], defaults={
                    'passed': TRAVIS_STATE[build['state']],
                    'started': parse_datetime(started),
                    'branch': branch,
                })

    def update(self, pull=True):
        self.project.update_tags()
        if pull:
            self.git().fetch()
        self.api_update()
        self.get_builds()


class Commit(NamedModel, TimeStampedModel):
    project = models.ForeignKey(Project, on_delete=models.CASCADE)

    class Meta:
        unique_together = ('project', 'name')


class Branch(TimeStampedModel):
    name = models.CharField(max_length=200)
    project = models.ForeignKey(Project, on_delete=models.CASCADE)
    ahead = models.PositiveSmallIntegerField(blank=True, null=True)
    behind = models.PositiveSmallIntegerField(blank=True, null=True)
    updated = models.DateTimeField(blank=True, null=True)
    repo = models.ForeignKey(Repo, on_delete=models.CASCADE, null=True)

    def __str__(self):
        return self.name

    class Meta:
        unique_together = ('project', 'name')

    def get_ahead(self, branch='master'):
        commits = self.project.git().git.rev_list(f'{branch}..{self}')
        return len(commits.split('\n')) if commits else 0

    def get_behind(self, branch='master'):
        commits = self.project.git().git.rev_list(f'{self}..{branch}')
        return len(commits.split('\n')) if commits else 0

    def git(self):
        git_repo = self.project.git()
        if self.name not in git_repo.branches:
            remote = self.repo.git()
            _, _, branch = self.name.split('/', maxsplit=2)
            git_repo.create_head(self.name, remote.refs[branch]).set_tracking_branch(remote.refs[branch])
        return git_repo.branches[self.name]

    def update(self, pull=True):
        if pull:
            self.project.main_repo().git().fetch()
            if self.name not in MAIN_BRANCHES:
                self.repo.git().fetch()
        main_branch = self.project.main_branch()
        self.ahead = self.get_ahead(main_branch)
        self.behind = self.get_behind(main_branch)
        self.updated = self.git().commit.authored_datetime
        self.save()

    def ci(self):
        build = self.cibuild_set.last()
        if build is None:
            return ''
        status = {True: '✓', False: '✗', None: '?'}[build.passed]
        return mark_safe(f'<a href="{build.url()}">{status}</a>')


class Test(TimeStampedModel):
    project = models.ForeignKey(Project, on_delete=models.CASCADE)
    branch = models.ForeignKey(Branch, on_delete=models.CASCADE)
    commit = models.ForeignKey(Commit, on_delete=models.CASCADE)
    target = models.PositiveSmallIntegerField(choices=enum_to_choices(TARGETS))
    passed = models.BooleanField(default=False)
    # TODO: travis vs gitlab-ci ?
    # TODO: deploy binary, doc, coverage, lint


class SystemDependency(NamedModel):
    project = models.ForeignKey(Project, on_delete=models.CASCADE)
    target = models.PositiveSmallIntegerField(choices=enum_to_choices(TARGETS))


class Robotpkg(NamedModel):
    project = models.ForeignKey(Project, on_delete=models.CASCADE)
    category = models.CharField(max_length=50)

    pkgbase = models.CharField(max_length=50, default='')
    pkgversion = models.CharField(max_length=20, default='')
    master_sites = models.CharField(max_length=200, default='')
    master_repository = models.CharField(max_length=200, default='')
    maintainer = models.CharField(max_length=200, default='')
    comment = models.TextField()
    homepage = models.URLField(max_length=200, default='')

    license = models.ForeignKey(License, on_delete=models.SET_NULL, blank=True, null=True)
    private = models.BooleanField(default=False)
    description = models.TextField()
    updated = models.DateTimeField(blank=True, null=True)

    def main_page(self):
        if self.category != 'wip':
            return f'{RPKG_URL}/robotpkg/{self.category}/{self.name}'

    def build_page(self):
        path = '-wip/wip' if self.category == 'wip' else f'/{self.category}'
        return f'{RPKG_URL}/rbulk/robotpkg{path}/{self.name}'

    def update(self, pull=True):
        path = settings.RAINBOARD_RPKG
        repo = git.Repo(str(path / 'wip' / '.git' if self.category == 'wip' else path / '.git'))
        if pull:
            repo.remotes.origin.pull()

        cwd = path / self.category / self.name
        for field in RPKG_FIELDS:
            cmd = ['make', 'show-var', f'VARNAME={field}']
            self.__dict__[field.lower()] = check_output(cmd, cwd=cwd).decode().strip()

        repo_path = self.name if self.category == 'wip' else f'{self.category}/{self.name}'
        last_commit = next(repo.iter_commits(paths=repo_path, max_count=1))
        self.updated = last_commit.authored_datetime

        license = check_output(['make', 'show-var', f'VARNAME=LICENSE'], cwd=cwd).decode().strip()
        if license in RPKG_LICENSES:
            self.license = License.objects.get(spdx_id=RPKG_LICENSES[license])
        else:
            logger.warning(f'Unknown robotpkg license: {license}')
        self.private = bool(check_output(['make', 'show-var', f'VARNAME=RESTRICTED'], cwd=cwd).decode().strip())
        with (cwd / 'DESCR').open() as f:
            self.description = f.read().strip()

        self.save()


class RobotpkgBuild(TimeStampedModel):
    robotpkg = models.ForeignKey(Robotpkg, on_delete=models.CASCADE)
    target = models.PositiveSmallIntegerField(choices=enum_to_choices(TARGETS))
    passed = models.BooleanField(default=False)


class CIBuild(models.Model):
    repo = models.ForeignKey(Repo, on_delete=models.CASCADE)
    passed = models.NullBooleanField()
    build_id = models.PositiveIntegerField()
    started = models.DateTimeField()
    branch = models.ForeignKey(Branch, on_delete=models.CASCADE)

    class Meta:
        ordering = ('started',)

    def url(self):
        if self.repo.forge.source == SOURCES.github:
            return f'https://travis-ci.org/{self.repo.namespace.slug}/{self.repo.slug}/builds/{self.build_id}'
        if self.repo.forge.source == SOURCES.gitlab:
            return f'{self.repo.forge.url}/{self.repo.namespace.slug}/{self.repo.slug}/pipelines/{self.build_id}'


class Tag(models.Model):
    name = models.CharField(max_length=200)
    slug = AutoSlugField(populate_from='name', slugify=slugify_with_dots)
    project = models.ForeignKey(Project, on_delete=models.CASCADE)

    class Meta:
        ordering = ('name',)
        unique_together = ('name', 'project')

# TODO: later
# class Dockerfile(NamedModel, TimeStampedModel):
    # project = models.ForeignKey(Project, on_delete=models.CASCADE)
    # target = models.PositiveSmallIntegerField(choices=enum_to_choices(TARGETS))