import subprocess
import re
import cgi
from odoo.modules.module import load_information_from_description_file
from odoo.tools import which

from .core import Check, CheckSuccess, CheckWarning, CheckFail


class DependencyCheck(Check):
    dependency_type = None

    def __init__(self, module, dependency):
        super(DependencyCheck, self).__init__(module)
        self.dependency = dependency

    def _dependency_installed(self, env, name):
        raise NotImplementedError("Should be overriden by the subclass")

    def _installed_version(self, env, name):
        raise NotImplementedError("Should be overriden by the subclass")

    def _details(self):
        if "install" in self.dependency:
            return "Install command: <pre>{}</pre>".format(self.dependency["install"])
        return None

    def __has_required_version(self, installed_version, version_expression):
        version_operator = "="
        version = self.dependency["version"]
        if version[:1] in ["=", "~", "^"]:
            version_operator = version[:1]
            version = version[1:]
        elif version[:2] in [">="]:
            version_operator = version[:2]
            version = version[2:]

        # Py3 : map -> list(map
        #  https://stackoverflow.com/questions/33717314/attributeerror-map-obejct-has-no-attribute-index-python-3
        try:
            parsed_version = list(map(int, version.split(".")))
        except ValueError:
            raise CheckFail(
                "Invalid version expression",
                details="""
Allowed expressions are <pre>=x.y.z</pre>, <pre>&gt;=x.y.z</pre>, <pre>^x.z.y</pre>,
<pre>~x.y.z. Got <pre>{}</pre>""".format(
                    cgi.escape(self.dependency["version"])
                ),
            )
        parsed_installed_version = list(map(int, installed_version.split(".")))

        parsed_version.extend(
            0 for _ in range(len(parsed_installed_version) - len(parsed_version))
        )
        parsed_installed_version.extend(
            0 for _ in range(len(parsed_version) - len(parsed_installed_version))
        )

        if version_operator == "^":
            if parsed_installed_version[:1] != parsed_version[:1]:
                return False
            version_operator = ">="
        elif version_operator == "~":
            if parsed_installed_version[:2] != parsed_version[:2]:
                return False
            version_operator = ">="

        if version_operator == ">=":
            return tuple(parsed_installed_version) >= tuple(parsed_version)
        elif version_operator == "=":
            return tuple(parsed_installed_version) == tuple(parsed_version)

        assert False

    def _run(self, env):
        name = self.dependency["name"]
        if not self._dependency_installed(env, name):
            raise CheckFail(
                "Required {} - {} - is not installed.".format(
                    self.dependency_type, name
                ),
                details=self._details(),
            )
        if "version" in self.dependency:
            version_expression = self.dependency["version"]
            installed_version = self._installed_version(env, name)
            if not self.__has_required_version(installed_version, version_expression):
                raise CheckWarning(
                    "Required {} - {} - has version {}, but {} is needed.".format(
                        self.dependency_type,
                        name,
                        installed_version,
                        version_expression,
                    ),
                    details=self._details(),
                )
        return CheckSuccess(
            "Required {} - {} - is installed.".format(self.dependency_type, name),
            details=self._details(),
        )


class InternalDependencyCheck(DependencyCheck):
    dependency_type = "Odoo module"

    def _dependency_installed(self, env, name):
        return name in env.registry._init_modules

    def _installed_version(self, env, name):
        return (
            env["ir.module.module"].sudo().search([("name", "=", name)]).latest_version
        )


class PythonDependencyCheck(DependencyCheck):
    dependency_type = "Python module"

    def _dependency_installed(self, env, name):
        try:
            __import__(name)
            return True
        except ImportError:
            return False

    def _installed_version(self, env, name):
        try:
            return __import__(name).__version__
        except AttributeError:
            raise CheckWarning(
                "Could not detect version of the Python module: {}.".format(name),
                details=self._details(),
            )


class ExternalDependencyCheck(DependencyCheck):
    dependency_type = "system executable"

    def _dependency_installed(self, env, name):
        try:
            which(name)
            return True
        except IOError:
            return False

    def _installed_version(self, env, name):
        try:
            exe = which(name)
            out = str(subprocess.check_output([exe, "--version"]))  # Py3 str()
            match = re.search("[\d.]+", out)
            if not match:
                raise CheckWarning(
                    "Unable to detect version for executable {}".format(name),
                    details="Command {} --version returned <pre>{}</pre>".format(
                        exe, out
                    ),
                )
            return match.group(0)
        except subprocess.CalledProcessError as e:
            raise CheckWarning(
                "Unable to detect version for executable {}: {}".format(name, e),
                details=self._details(),
            )


def get_checks_for_module(module_name):
    result = []

    manifest = load_information_from_description_file(module_name)
    manifest_checks = manifest.get("environment_checkup") or {}
    dependencies = manifest_checks.get("dependencies") or {}

    for dependency in dependencies.get("python") or []:
        result.append(PythonDependencyCheck(module_name, dependency))
    for dependency in dependencies.get("external") or []:
        result.append(ExternalDependencyCheck(module_name, dependency))
    for dependency in dependencies.get("internal") or []:
        result.append(InternalDependencyCheck(module_name, dependency))

    return result


def get_checks_for_module_recursive(module):
    class ModuleDFS(object):
        def __init__(self):
            self.visited_modules = set()
            self.checks = []

        def visit(self, module):
            if module.name in self.visited_modules:
                return
            self.visited_modules.add(module.name)
            self.checks += get_checks_for_module(module.name)
            for module_dependency in module.dependencies_id:
                if module_dependency.depend_id:
                    self.visit(module_dependency.depend_id)
            return self

    return ModuleDFS().visit(module).checks