from contextlib import suppress

import json
import os
import re
import shutil
import subprocess
import sys
from distutils import core
from typing import Dict, Any

from .generateChangelog import generateDebianChangelog

# Maximum allowed repository size difference (in kB) following merge.
# This is used to prevent large files from being inappropriately added to
# the repository history.
MERGE_SIZE_LIMIT = 100

# Paths that are checked for style by flake and flake_diff
FLAKE_CHECK_PATHS = ['pyqtgraph', 'examples', 'tools']

# Flake style checks -- mandatory, recommended, optional
# See: http://pep8.readthedocs.org/en/1.4.6/intro.html
# and  https://flake8.readthedocs.org/en/2.0/warnings.html
FLAKE_MANDATORY = set([
    'E101',  #  indentation contains mixed spaces and tabs
    'E112',  #  expected an indented block
    'E122',  #  continuation line missing indentation or outdented
    'E125',  #  continuation line does not distinguish itself from next line
    'E133',  #  closing bracket is missing indentation

    'E223',  #  tab before operator
    'E224',  #  tab after operator
    'E242',  #  tab after ‘,’
    'E273',  #  tab after keyword
    'E274',  #  tab before keyword

    'E901',  #  SyntaxError or IndentationError
    'E902',  #  IOError

    'W191',  #  indentation contains tabs

    'W601',  #  .has_key() is deprecated, use ‘in’
    'W602',  #  deprecated form of raising exception
    'W603',  #  ‘<>’ is deprecated, use ‘!=’
    'W604',  #  backticks are deprecated, use ‘repr()’
    ])

FLAKE_RECOMMENDED = set([
    'E124',  #  closing bracket does not match visual indentation
    'E231',  #  missing whitespace after ‘,’

    'E211',  #  whitespace before ‘(‘
    'E261',  #  at least two spaces before inline comment
    'E271',  #  multiple spaces after keyword
    'E272',  #  multiple spaces before keyword
    'E304',  #  blank lines found after function decorator

    'F401',  #  module imported but unused
    'F402',  #  import module from line N shadowed by loop variable
    'F403',  #  ‘from module import *’ used; unable to detect undefined names
    'F404',  #  future import(s) name after other statements

    'E501',  #  line too long (82 > 79 characters)
    'E502',  #  the backslash is redundant between brackets

    'E702',  #  multiple statements on one line (semicolon)
    'E703',  #  statement ends with a semicolon
    'E711',  #  comparison to None should be ‘if cond is None:’
    'E712',  #  comparison to True should be ‘if cond is True:’ or ‘if cond:’
    'E721',  #  do not compare types, use ‘isinstance()’

    'F811',  #  redefinition of unused name from line N
    'F812',  #  list comprehension redefines name from line N
    'F821',  #  undefined name name
    'F822',  #  undefined name name in __all__
    'F823',  #  local variable name ... referenced before assignment
    'F831',  #  duplicate argument name in function definition
    'F841',  #  local variable name is assigned to but never used

    'W292',  #  no newline at end of file

    ])

FLAKE_OPTIONAL = set([
    'E121',  #  continuation line indentation is not a multiple of four
    'E123',  #  closing bracket does not match indentation of opening bracket
    'E126',  #  continuation line over-indented for hanging indent
    'E127',  #  continuation line over-indented for visual indent
    'E128',  #  continuation line under-indented for visual indent

    'E201',  #  whitespace after ‘(‘
    'E202',  #  whitespace before ‘)’
    'E203',  #  whitespace before ‘:’
    'E221',  #  multiple spaces before operator
    'E222',  #  multiple spaces after operator
    'E225',  #  missing whitespace around operator
    'E227',  #  missing whitespace around bitwise or shift operator
    'E226',  #  missing whitespace around arithmetic operator
    'E228',  #  missing whitespace around modulo operator
    'E241',  #  multiple spaces after ‘,’
    'E251',  #  unexpected spaces around keyword / parameter equals
    'E262',  #  inline comment should start with ‘# ‘

    'E301',  #  expected 1 blank line, found 0
    'E302',  #  expected 2 blank lines, found 0
    'E303',  #  too many blank lines (3)

    'E401',  #  multiple imports on one line

    'E701',  #  multiple statements on one line (colon)

    'W291',  #  trailing whitespace
    'W293',  #  blank line contains whitespace

    'W391',  #  blank line at end of file
    ])

FLAKE_IGNORE = set([
    # 111 and 113 are ignored because they appear to be broken.
    'E111',  #  indentation is not a multiple of four
    'E113',  #  unexpected indentation
    ])


def checkStyle():
    """ Run flake8, checking only lines that are modified since the last
    git commit. """

    # First check _all_ code against mandatory error codes
    print('flake8: check all code against mandatory error set...')
    errors = ','.join(FLAKE_MANDATORY)
    cmd = ['flake8', '--select=' + errors] + FLAKE_CHECK_PATHS
    proc = subprocess.Popen(cmd, stdout=subprocess.PIPE)
    #ret = proc.wait()
    output = proc.stdout.read().decode('utf-8')
    ret = proc.wait()
    printFlakeOutput(output)

    # Check for DOS newlines
    print('check line endings in all files...')
    count = 0
    allowedEndings = set([None, '\n'])
    for path, dirs, files in os.walk('.'):
        if path.startswith("." + os.path.sep + ".tox"):
            continue
        for f in files:
            if os.path.splitext(f)[1] not in ('.py', '.rst'):
                continue
            filename = os.path.join(path, f)
            with open(filename, 'U') as fh:
                _ = fh.readlines()
                endings = set(
                    fh.newlines
                    if isinstance(fh.newlines, tuple)
                    else (fh.newlines,)
                )
                endings -= allowedEndings
                if len(endings) > 0:
                    print("\033[0;31m"
                          + "File has invalid line endings: "
                          + "%s" % filename + "\033[0m")
                    ret = ret | 2
                count += 1
    print('checked line endings in %d files' % count)


    # Next check new code with optional error codes
    print('flake8: check new code against recommended error set...')
    diff = subprocess.check_output(['git', 'diff'])
    proc = subprocess.Popen(['flake8', '--diff',  # '--show-source',
                                '--ignore=' + errors],
                            stdin=subprocess.PIPE,
                            stdout=subprocess.PIPE)
    proc.stdin.write(diff)
    proc.stdin.close()
    output = proc.stdout.read().decode('utf-8')
    ret |= printFlakeOutput(output)

    if ret == 0:
        print('style test passed.')
    else:
        print('style test failed: %d' % ret)
    return ret

def printFlakeOutput(text):
    """ Print flake output, colored by error category.
    Return 2 if there were any mandatory errors,
    1 if only recommended / optional errors, and
    0 if only optional errors.
    """
    ret = 0
    gotError = False
    for line in text.split('\n'):
        m = re.match(r'[^\:]+\:\d+\:\d+\: (\w+) .*', line)
        if m is None:
            print(line)
        else:
            gotError = True
            error = m.group(1)
            if error in FLAKE_MANDATORY:
                print("\033[0;31m" + line + "\033[0m")
                ret |= 2
            elif error in FLAKE_RECOMMENDED:
                print("\033[0;33m" + line + "\033[0m")
                #ret |= 1
            elif error in FLAKE_OPTIONAL:
                print("\033[0;32m" + line + "\033[0m")
            elif error in FLAKE_IGNORE:
                continue
            else:
                print("\033[0;36m" + line + "\033[0m")
    if not gotError:
        print("    [ no errors ]\n")
    return ret



def unitTests():
    """
    Run all unit tests (using py.test)
    Return the exit code.
    """
    try:
        if sys.version[0] == '3':
            out = subprocess.check_output('PYTHONPATH=. py.test-3', shell=True)
        else:
            out = subprocess.check_output('PYTHONPATH=. py.test', shell=True)
        ret = 0
    except Exception as e:
        out = e.output
        ret = e.returncode
    print(out.decode('utf-8'))
    return ret


def checkMergeSize(
    sourceBranch=None,
    targetBranch=None,
    sourceRepo=None,
    targetRepo=None
):
    """
    Check that a git merge would not increase the repository size by
    MERGE_SIZE_LIMIT.
    """
    if sourceBranch is None:
        sourceBranch = getGitBranch()
        sourceRepo = '..'

    if targetBranch is None:
        if sourceBranch == 'master':
            targetBranch = 'master'
            targetRepo = 'https://github.com/pyqtgraph/pyqtgraph.git'
        else:
            targetBranch = 'master'
            targetRepo = '..'

    workingDir = '__merge-test-clone'
    env = dict(TARGET_BRANCH=targetBranch,
               SOURCE_BRANCH=sourceBranch,
               TARGET_REPO=targetRepo,
               SOURCE_REPO=sourceRepo,
               WORKING_DIR=workingDir,
               )

    print("Testing merge size difference:\n"
          "  SOURCE: {SOURCE_REPO} {SOURCE_BRANCH}\n"
          "  TARGET: {TARGET_BRANCH} {TARGET_REPO}".format(**env))

    setup = """
        mkdir {WORKING_DIR} && cd {WORKING_DIR} &&
        git init && git remote add -t {TARGET_BRANCH} target {TARGET_REPO} &&
        git fetch target {TARGET_BRANCH} &&
        git checkout -qf target/{TARGET_BRANCH} &&
        git gc -q --aggressive
        """.format(**env)

    checkSize = """
        cd {WORKING_DIR} &&
        du -s . | sed -e "s/\t.*//"
        """.format(**env)

    merge = """
        cd {WORKING_DIR} &&
        git pull -q {SOURCE_REPO} {SOURCE_BRANCH} &&
        git gc -q --aggressive
        """.format(**env)

    try:
        print("Check out target branch:\n" + setup)
        subprocess.check_call(setup, shell=True)
        targetSize = int(subprocess.check_output(checkSize, shell=True))
        print("TARGET SIZE: %d kB" % targetSize)
        print("Merge source branch:\n" + merge)
        subprocess.check_call(merge, shell=True)
        mergeSize = int(subprocess.check_output(checkSize, shell=True))
        print("MERGE SIZE: %d kB" % mergeSize)

        diff = mergeSize - targetSize
        if diff <= MERGE_SIZE_LIMIT:
            print("DIFFERENCE: %d kB  [OK]" % diff)
            return 0
        else:
            print("\033[0;31m"
                  + "DIFFERENCE: %d kB  [exceeds %d kB]" % (
                      diff,
                      MERGE_SIZE_LIMIT)
                  + "\033[0m")
            return 2
    finally:
        if os.path.isdir(workingDir):
            shutil.rmtree(workingDir)


def mergeTests():
    ret = checkMergeSize()
    ret |= unitTests()
    ret |= checkStyle()
    if ret == 0:
        print("\033[0;32m" + "\nAll merge tests passed." + "\033[0m")
    else:
        print("\033[0;31m" + "\nMerge tests failed." + "\033[0m")
    return ret


def getInitVersion(pkgroot):
    """Return the version string defined in __init__.py"""
    path = os.getcwd()
    initfile = os.path.join(path, pkgroot, '__init__.py')
    init = open(initfile).read()
    m = re.search(r'__version__ = (\S+)\n', init)
    if m is None or len(m.groups()) != 1:
        raise Exception("Cannot determine __version__ from init file: "
                        + "'%s'!" % initfile)
    version = m.group(1).strip('\'\"')
    return version

def gitCommit(name):
    """Return the commit ID for the given name."""
    commit = subprocess.check_output(
        ['git', 'show', name],
        universal_newlines=True).split('\n')[0]
    assert commit[:7] == 'commit '
    return commit[7:]

def getGitVersion(tagPrefix):
    """Return a version string with information about this git checkout.
    If the checkout is an unmodified, tagged commit, then return the tag
    version

    If this is not a tagged commit, return the output of
    ``git describe --tags``

    If this checkout has been modified, append "+" to the version.
    """
    path = os.getcwd()
    if not os.path.isdir(os.path.join(path, '.git')):
        return None

    try:
        v = (
            subprocess.check_output(
                ["git", "describe", "--tags", "--dirty", '--match="%s*"' % tagPrefix],
                stderr=subprocess.DEVNULL)
            .strip()
            .decode("utf-8")
        )
    except (FileNotFoundError, subprocess.CalledProcessError):
        return None

    # chop off prefix
    assert v.startswith(tagPrefix)
    v = v[len(tagPrefix):]

    # split up version parts
    parts = v.split('-')

    # has working tree been modified?
    modified = False
    if parts[-1] == 'dirty':
        modified = True
        parts = parts[:-1]

    # have commits been added on top of last tagged version?
    # (git describe adds -NNN-gXXXXXXX if this is the case)
    local = None
    if (len(parts) > 2 and
        re.match(r'\d+', parts[-2]) and
        re.match(r'g[0-9a-f]{7}', parts[-1])):
        local = parts[-1]
        parts = parts[:-2]

    gitVersion = '-'.join(parts)
    if local is not None:
        gitVersion += '+' + local
    if modified:
        gitVersion += 'm'

    return gitVersion

def getGitBranch():
    m = re.search(
        r'\* (.*)',
        subprocess.check_output(['git', 'branch'],
        universal_newlines=True))
    if m is None:
        return ''
    else:
        return m.group(1)

def getVersionStrings(pkg):
    """
    Returns 4 version strings:

      * the version string to use for this build,
      * version string requested with --force-version (or None)
      * version string that describes the current git checkout (or None).
      * version string in the pkg/__init__.py,

    The first return value is (forceVersion or gitVersion or initVersion).
    """

    ## Determine current version string from __init__.py
    initVersion = getInitVersion(pkgroot=pkg)

    # If this is a git checkout
    # try to generate a more descriptive version string
    try:
        gitVersion = getGitVersion(tagPrefix=pkg+'-')
    except:
        gitVersion = None
        sys.stderr.write("This appears to be a git checkout, but an error "
                        "occurred while attempting to determine a version "
                        "string for the current commit.\n")
        sys.excepthook(*sys.exc_info())

    # See whether a --force-version flag was given
    forcedVersion = None
    for i, arg in enumerate(sys.argv):
        if arg.startswith('--force-version'):
            if arg == '--force-version':
                forcedVersion = sys.argv[i+1]
                sys.argv.pop(i)
                sys.argv.pop(i)
            elif arg.startswith('--force-version='):
                forcedVersion = sys.argv[i].replace('--force-version=', '')
                sys.argv.pop(i)


    ## Finally decide on a version string to use:
    if forcedVersion is not None:
        version = forcedVersion
    else:
        version = initVersion
        # if git says this is a modified branch, add local version information
        if gitVersion is not None:
            _, _, local = gitVersion.partition('+')
            if local != '':
                version = version + '+' + local
                sys.stderr.write("Detected git commit; "
                                 + "will use version string: '%s'\n" % version)

    return version, forcedVersion, gitVersion, initVersion


DEFAULT_ASV: Dict[str, Any] = {
    "version": 1,
    "project": "pyqtgraph",
    "project_url": "http://pyqtgraph.org/",
    "repo": ".",
    "branches": ["master"],
    "environment_type": "virtualenv",
    "show_commit_url": "http://github.com/pyqtgraph/pyqtgraph/commit/",
    # "pythons": ["3.7", "3.8", "3.9"],
    "matrix": {
        # "numpy": ["1.17", "1.18", "1.19", ""],
        "numpy": "",
        "pyqt5": ["", None],
        "pyside2": ["", None],
    },
    "exclude": [
        {"pyqt5": "", "pyside2": ""},
        {"pyqt5": None, "pyside2": None}
    ],
    "benchmark_dir": "benchmarks",
    "env_dir": ".asv/env",
    "results_dir": ".asv/results",
    "html_dir": ".asv/html",
    "build_cache_size": 5
}


class ASVConfigCommand(core.Command):
    description = "Setup the ASV benchmarking config for this system"
    user_options = []

    def initialize_options(self) -> None:
        pass

    def finalize_options(self) -> None:
        pass

    def run(self) -> None:
        config = DEFAULT_ASV
        with suppress(FileNotFoundError, subprocess.CalledProcessError):
            cuda_check = subprocess.check_output(["nvcc", "--version"])
            match = re.search(r"release (\d{1,2}\.\d)", cuda_check.decode("utf-8"))
            ver = match.groups()[0]  # e.g. 11.0
            ver_str = ver.replace(".", "")  # e.g. 110
            config["matrix"][f"cupy-cuda{ver_str}"] = ""

        with open("asv.conf.json", "w") as conf_file:
            conf_file.write(json.dumps(config, indent=2))


class DebCommand(core.Command):
    description = "build .deb package using `debuild -us -uc`"
    maintainer = "Luke Campagnola <luke.campagnola@gmail.com>"
    debTemplate = "debian"
    debDir = "deb_build"

    user_options = []

    def initialize_options(self):
        self.cwd = None

    def finalize_options(self):
        self.cwd = os.getcwd()

    def run(self):
        version = self.distribution.get_version()
        pkgName = self.distribution.get_name()
        debName = "python-" + pkgName
        debDir = self.debDir

        assert os.getcwd() == self.cwd, 'Must be in package root: %s' % self.cwd

        if os.path.isdir(debDir):
            raise Exception('DEB build dir already exists: "%s"' % debDir)
        sdist = "dist/%s-%s.tar.gz" % (pkgName, version)
        if not os.path.isfile(sdist):
            raise Exception("No source distribution; "
                            + "run `setup.py sdist` first.")

        # copy sdist to build directory and extract
        os.mkdir(debDir)
        renamedSdist = '%s_%s.orig.tar.gz' % (debName, version)
        print("copy %s => %s" % (sdist, os.path.join(debDir, renamedSdist)))
        shutil.copy(sdist, os.path.join(debDir, renamedSdist))
        print("cd %s; tar -xzf %s" % (debDir, renamedSdist))
        if os.system("cd %s; tar -xzf %s" % (debDir, renamedSdist)) != 0:
            raise Exception("Error extracting source distribution.")
        buildDir = '%s/%s-%s' % (debDir, pkgName, version)

        # copy debian control structure
        print("copytree %s => %s" % (self.debTemplate, buildDir+'/debian'))
        shutil.copytree(self.debTemplate, buildDir+'/debian')

        # Write new changelog
        chlog = generateDebianChangelog(
            pkgName,
            'CHANGELOG',
            version,
            self.maintainer)
        print("write changelog %s" % buildDir+'/debian/changelog')
        open(buildDir+'/debian/changelog', 'w').write(chlog)

        # build package
        print('cd %s; debuild -us -uc' % buildDir)
        if os.system('cd %s; debuild -us -uc' % buildDir) != 0:
            raise Exception("Error during debuild.")


class DebugCommand(core.Command):
    """Just for learning about distutils."""
    description = ""
    user_options = []
    def initialize_options(self):
        pass
    def finalize_options(self):
        pass
    def run(self):
        global cmd
        cmd = self
        print(self.distribution.name)
        print(self.distribution.version)


class TestCommand(core.Command):
    description =  "Run all package tests and exit immediately with ", \
                   "informative return code."
    user_options = []

    def run(self):
        sys.exit(unitTests())

    def initialize_options(self):
        pass

    def finalize_options(self):
        pass


class StyleCommand(core.Command):
    description = "Check all code for style, exit immediately with ", \
                  "informative return code."
    user_options = []

    def run(self):
        sys.exit(checkStyle())

    def initialize_options(self):
        pass

    def finalize_options(self):
        pass


class MergeTestCommand(core.Command):
    description = "Run all tests needed to determine whether the current ",\
                  "code is suitable for merge."
    user_options = []

    def run(self):
        sys.exit(mergeTests())

    def initialize_options(self):
        pass

    def finalize_options(self):
        pass