# Copyright © 2022, 2023 Vulcanize

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http:#www.gnu.org/licenses/>.

import hashlib
import os
from pathlib import Path

from stack_orchestrator import constants
from stack_orchestrator.util import get_yaml
from stack_orchestrator.deploy.stack import Stack
from stack_orchestrator.deploy.spec import Spec


class DeploymentContext:
    deployment_dir: Path
    id: str
    deployment_id: str
    spec: Spec
    stack: Stack

    def get_stack_file(self):
        return self.deployment_dir.joinpath(constants.stack_file_name)

    def get_spec_file(self):
        return self.deployment_dir.joinpath(constants.spec_file_name)

    def get_env_file(self):
        return self.deployment_dir.joinpath(constants.config_file_name)

    def get_deployment_file(self):
        return self.deployment_dir.joinpath(constants.deployment_file_name)

    def get_compose_dir(self):
        return self.deployment_dir.joinpath(constants.compose_dir_name)

    def get_compose_file(self, name: str):
        return self.get_compose_dir() / f"docker-compose-{name}.yml"

    def get_cluster_id(self):
        """Identifier of the kind cluster this deployment attaches to.

        Shared across deployments that join the same kind cluster. Used
        for the kube-config context name (`kind-{cluster-id}`) and for
        kind cluster lifecycle ops.
        """
        return self.id

    def get_deployment_id(self):
        """Identifier of this particular deployment's k8s resources.

        Distinct per deployment even when multiple deployments share a
        cluster. Used as compose_project_name → app_name → prefix for
        all k8s resource names (PVs, ConfigMaps, Deployments, …).

        Backward compat: for deployment.yml files written before this
        field existed, falls back to cluster-id so existing on-disk
        resource names remain stable (no PV renames, no re-bind).
        """
        return self.deployment_id

    def init(self, dir: Path):
        self.deployment_dir = dir.absolute()
        self.spec = Spec()
        self.spec.init_from_file(self.get_spec_file())
        self.stack = Stack(self.spec.obj["stack"])
        self.stack.init_from_file(self.get_stack_file())
        deployment_file_path = self.get_deployment_file()
        if deployment_file_path.exists():
            obj = get_yaml().load(open(deployment_file_path, "r"))
            self.id = obj[constants.cluster_id_key]
            # Fallback to cluster-id for deployments created before the
            # deployment-id field was introduced. Keeps existing resource
            # names stable across this upgrade.
            self.deployment_id = obj.get(
                constants.deployment_id_key, self.id
            )
        # Handle the case of a legacy deployment with no file
        # Code below is intended to match the output from _make_default_cluster_name()
        # TODO: remove when we no longer need to support legacy deployments
        else:
            path = os.path.realpath(os.path.abspath(self.get_compose_dir()))
            unique_cluster_descriptor = f"{path},{self.get_stack_file()},None,None"
            hash = hashlib.md5(unique_cluster_descriptor.encode()).hexdigest()[:16]
            self.id = f"{constants.cluster_name_prefix}{hash}"
            self.deployment_id = self.id

    def modify_yaml(self, file_path: Path, modifier_func):
        """Load a YAML, apply a modification function, and write it back."""
        if not file_path.absolute().is_relative_to(self.deployment_dir):
            raise ValueError(f"File is not inside deployment directory: {file_path}")

        yaml = get_yaml()
        with open(file_path, "r") as f:
            yaml_data = yaml.load(f)

        modifier_func(yaml_data)

        with open(file_path, "w") as f:
            yaml.dump(yaml_data, f)