import importlib
import inspect
import json
import logging
import glob
import os
import pkgutil
from pathlib import Path
import subprocess
import sys
import types
from typing import Dict, Any, Optional

# Because I'm subprocessing myself, I need to do weird thing as import.
try:
    # If I'm started as a module __main__
    from .venvtools import create_venv_with_package
except (ModuleNotFoundError, ImportError) as e:
    # If I'm started by my main directly
    from venvtools import create_venv_with_package


_LOGGER = logging.getLogger(__name__)

def parse_input(input_parameter):
    """From a syntax like package_name#submodule, build a package name
    and complete module name.
    """
    split_package_name = input_parameter.split('#')
    package_name = split_package_name[0]
    module_name = package_name.replace("-", ".")
    if len(split_package_name) >= 2:
        module_name = ".".join([module_name, split_package_name[1]])
    return package_name, module_name

def create_empty_report():
    return {
        "models": {
            "enums": {},
            "exceptions": {},
            "models": {}
        },
        "operations": {}
    }

def create_report(module_name: str) -> Dict[str, Any]:
    module_to_generate = importlib.import_module(module_name)

    report = create_empty_report()

    # Look for models first
    model_names = [model_name for model_name in dir(module_to_generate.models) if model_name[0].isupper()]
    for model_name in model_names:
        model_cls = getattr(module_to_generate.models, model_name)
        if hasattr(model_cls, "_attribute_map"):
            report["models"]["models"][model_name] = create_model_report(model_cls)
        elif issubclass(model_cls, Exception): # If not, might be an exception
            report["models"]["exceptions"][model_name] = create_model_report(model_cls)
        else:
            report["models"]["enums"][model_name] = create_model_report(model_cls)
    # Look for operation groups
    try:
        operations_classes = [op_name for op_name in dir(module_to_generate.operations) if op_name[0].isupper()]
    except AttributeError:
        # This guy has no "operations", this is possible (Cognitive Services). Just skip it then.
        operations_classes = []

    for op_name in operations_classes:
        op_content = {'name': op_name}
        op_cls = getattr(module_to_generate.operations, op_name)
        for op_attr_name in dir(op_cls):
            op_attr = getattr(op_cls, op_attr_name)
            if isinstance(op_attr, types.FunctionType) and not op_attr_name.startswith("_"):
                # Keep it
                func_content = create_report_from_func(op_attr)
                op_content.setdefault("functions", {})[op_attr_name] = func_content
        report['operations'][op_name] = op_content

    return report

def create_model_report(model_cls):
    result = {
        'name': model_cls.__name__,
    }
    # If _attribute_map, it's a model
    if hasattr(model_cls, "_attribute_map"):
        result['type'] = "Model"
        for attribute, conf in model_cls._attribute_map.items():
            attribute_validation = getattr(model_cls, "_validation", {}).get(attribute, {})

            result.setdefault('parameters', {})[attribute] = {
                'name': attribute,
                'properties': {
                    'type': conf['type'],
                    'required': attribute_validation.get('required', False),
                    'readonly': attribute_validation.get('readonly', False)
                }
            }
    elif issubclass(model_cls, Exception): # If not, might be an exception
        result['type'] = "Exception"
    else: # If not, it's an enum
        result['type'] = "Enum"
        result['values'] = list(model_cls.__members__)

    return result

def create_report_from_func(function_attr):
    func_content = {
        'name': function_attr.__name__,
        'metadata': getattr(function_attr, "metadata", {}),
        'parameters': []
    }
    signature = inspect.signature(function_attr)
    for parameter_name in signature.parameters:
        if parameter_name == "self":
            continue
        if parameter_name =="custom_headers":
            break # We reach Autorest generic
        parameter = signature.parameters[parameter_name]
        func_content["parameters"].append({
            'name': parameter.name,
        })
    return func_content

# given an input of a name, we need to return the appropriate relative diff between the sdk_root and the actual package directory
def resolve_package_directory(package_name):
    packages = [os.path.dirname(p) for p in (glob.glob('{}/setup.py'.format(package_name)) + glob.glob('sdk/*/{}/setup.py'.format(package_name)))]

    if len(packages) > 1:
        print('There should only be a single package matched in either repository structure. The following were found: {}'.format(packages))
        sys.exit(1)

    return packages[0]

def merge_report(report_paths):
    """Merge report on the given paths list.
    """
    if len(report_paths) == 1:
        raise ValueError("Doesn't make sense to merge a report if there is only one report....")

    merged_report = create_empty_report()
    for report in sorted(report_paths):
        with report.open() as report_fd:
            report_json = json.load(report_fd)

        merged_report["models"]["enums"].update(report_json["models"]["enums"])
        merged_report["models"]["exceptions"].update(report_json["models"]["exceptions"])
        merged_report["models"]["models"].update(report_json["models"]["models"])
        merged_report["operations"].update(report_json["operations"])
    return merged_report

def main(input_parameter: str, version: Optional[str] = None, no_venv: bool = False, pypi: bool = False, last_pypi: bool = False, output: str = None):
    package_name, module_name = parse_input(input_parameter)
    path_to_package = resolve_package_directory(package_name)

    if (version or pypi or last_pypi) and not no_venv:
        if version:
            versions = [version]
        else:
            _LOGGER.info(f"Download versions of {package_name} on PyPI")
            from pypi_tools.pypi import PyPIClient
            client = PyPIClient()
            versions = [str(v) for v in client.get_ordered_versions(package_name)]
            _LOGGER.info(f"Got {versions}")
            if last_pypi:
                _LOGGER.info(f"Only keep last PyPI version")
                versions = [versions[-1]]

        for version in versions:
            _LOGGER.info(f"Installing version {version} of {package_name} in a venv")
            with create_venv_with_package([f"{package_name}=={version}"]) as venv:
                args = [
                    venv.env_exe,
                    __file__,
                    "--no-venv",
                    "--version",
                    version,
                    input_parameter
                ]
                if output is not None:
                    args.append("--output=" + output)
                try:
                    subprocess.check_call(args)
                except subprocess.CalledProcessError:
                    # If it fail, just assume this version is too old to get an Autorest report
                    _LOGGER.warning(f"Version {version} seems to be too old to build a report (probably not Autorest based)")
        # Files have been written by the subprocess
        return

    modules = find_autorest_generated_folder(module_name)
    result = []
    version = version or "latest"
    output_folder = Path(path_to_package) / Path("code_reports") / Path(version)
    output_folder.mkdir(parents=True, exist_ok=True)

    for module_name in modules:
        _LOGGER.info(f"Working on {module_name}")

        report = create_report(module_name)

        module_for_path = get_sub_module_part(package_name, module_name)
        if module_for_path:
            output_filename = output_folder / Path(module_for_path+".json")
        else:
            if output is not None:
                output_filename = output
            else:
                output_filename = output_folder / Path("report.json")

        with open(output_filename, "w") as fd:
            json.dump(report, fd, indent=2)
            _LOGGER.info(f"Report written to {output_filename}")
        result.append(output_filename)

    if len(result) > 1:
        merged_report = merge_report(result)
        if output is not None:
            output_filename = output
        else:
            output_filename = output_folder / Path("merged_report.json")
        with open(output_filename, "w") as fd:
            json.dump(merged_report, fd, indent=2)
            _LOGGER.info(f"Merged report written to {output_filename}")

    return result

def find_autorest_generated_folder(module_prefix="azure"):
    """Find all Autorest generated code in that module prefix.
    This actually looks for a "models" package only (not file). We could be smarter if necessary.
    """
    _LOGGER.info(f"Looking for Autorest generated package in {module_prefix}")

    # Manually skip some namespaces for now
    if module_prefix in ["azure.cli", "azure.storage", "azure.servicemanagement", "azure.servicebus"]:
        _LOGGER.info(f"Skip {module_prefix}")
        return []

    result = []
    try:
        _LOGGER.debug(f"Try {module_prefix}")
        model_module = importlib.import_module(".models", module_prefix)
        # If not exception, we MIGHT have found it, but cannot be a file.
        # Keep continue to try to break it, file module have no __path__
        model_module.__path__
        _LOGGER.info(f"Found {module_prefix}")
        result.append(module_prefix)
    except (ModuleNotFoundError, AttributeError):
        # No model, might dig deeper
        prefix_module = importlib.import_module(module_prefix)
        for _, sub_package, ispkg in pkgutil.iter_modules(prefix_module.__path__, module_prefix+"."):
            if ispkg:
                result += find_autorest_generated_folder(sub_package)
    return result


def get_sub_module_part(package_name, module_name):
    """Assuming package is azure-mgmt-compute and module name is azure.mgmt.compute.v2018-08-01
    will return v2018-08-01
    """
    sub_module_from_package = package_name.replace("-", ".")
    if not module_name.startswith(sub_module_from_package):
        _LOGGER.warning(f"Submodule {module_name} does not start with package name {package_name}")
        return
    return module_name[len(sub_module_from_package)+1:]


if __name__ == "__main__":
    import argparse

    parser = argparse.ArgumentParser(
        description='Code fingerprint building',
        formatter_class=argparse.RawTextHelpFormatter,
    )
    parser.add_argument('package_name',
                        help='Package name.')
    parser.add_argument('--version', '-v',
                        dest='version',
                        help='The version of the package you want. By default, latest and current branch.')
    parser.add_argument('--no-venv',
                        dest='no_venv', action="store_true",
                        help="If version is provided, this will assume the current accessible package is already this version. You should probably not use it.")
    parser.add_argument('--pypi',
                        dest='pypi', action="store_true",
                        help="If provided, build report for all versions on pypi of this package.")
    parser.add_argument('--last-pypi',
                        dest='last_pypi', action="store_true",
                        help="If provided, build report for last version on pypi of this package.")
    parser.add_argument("--debug",
                        dest="debug", action="store_true",
                        help="Verbosity in DEBUG mode")
    parser.add_argument("--output",
                        dest="output",
                        help="Override output path.")
    args = parser.parse_args()

    logging.basicConfig(level=logging.DEBUG if args.debug else logging.INFO)

    main(args.package_name, args.version, args.no_venv, args.pypi, args.last_pypi, args.output)