/*
Copyright 2022 The Matrix.org Foundation C.I.C.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

/// <reference types="cypress" />

import * as os from "os";
import * as crypto from "crypto";
import * as childProcess from "child_process";
import * as fse from "fs-extra";

import PluginEvents = Cypress.PluginEvents;
import PluginConfigOptions = Cypress.PluginConfigOptions;

// A cypress plugin to run docker commands

export async function dockerRun(opts: {
    image: string;
    containerName: string;
    params?: string[];
    cmd?: string[];
}): Promise<string> {
    const userInfo = os.userInfo();
    const params = opts.params ?? [];

    if (params?.includes("-v") && userInfo.uid >= 0) {
        // On *nix we run the docker container as our uid:gid otherwise cleaning it up its media_store can be difficult
        params.push("-u", `${userInfo.uid}:${userInfo.gid}`);

        if (await isPodman()) {
            // keep the user ID if the docker command is actually podman
            params.push("--userns=keep-id");
        }
    }

    const args = [
        "run",
        "--name",
        `${opts.containerName}-${crypto.randomBytes(4).toString("hex")}`,
        "-d",
        ...params,
        opts.image,
    ];

    if (opts.cmd) args.push(...opts.cmd);

    return new Promise<string>((resolve, reject) => {
        childProcess.execFile("docker", args, (err, stdout) => {
            if (err) reject(err);
            resolve(stdout.trim());
        });
    });
}

export function dockerExec(args: { containerId: string; params: string[] }): Promise<void> {
    return new Promise<void>((resolve, reject) => {
        childProcess.execFile(
            "docker",
            ["exec", args.containerId, ...args.params],
            { encoding: "utf8" },
            (err, stdout, stderr) => {
                if (err) {
                    console.log(stdout);
                    console.log(stderr);
                    reject(err);
                    return;
                }
                resolve();
            },
        );
    });
}

export async function dockerLogs(args: {
    containerId: string;
    stdoutFile?: string;
    stderrFile?: string;
}): Promise<void> {
    const stdoutFile = args.stdoutFile ? await fse.open(args.stdoutFile, "w") : "ignore";
    const stderrFile = args.stderrFile ? await fse.open(args.stderrFile, "w") : "ignore";

    await new Promise<void>((resolve) => {
        childProcess
            .spawn("docker", ["logs", args.containerId], {
                stdio: ["ignore", stdoutFile, stderrFile],
            })
            .once("close", resolve);
    });

    if (args.stdoutFile) await fse.close(<number>stdoutFile);
    if (args.stderrFile) await fse.close(<number>stderrFile);
}

export function dockerStop(args: { containerId: string }): Promise<void> {
    return new Promise<void>((resolve, reject) => {
        childProcess.execFile("docker", ["stop", args.containerId], (err) => {
            if (err) reject(err);
            resolve();
        });
    });
}

export function dockerRm(args: { containerId: string }): Promise<void> {
    return new Promise<void>((resolve, reject) => {
        childProcess.execFile("docker", ["rm", args.containerId], (err) => {
            if (err) reject(err);
            resolve();
        });
    });
}

export function dockerIp(args: { containerId: string }): Promise<string> {
    return new Promise<string>((resolve, reject) => {
        childProcess.execFile(
            "docker",
            ["inspect", "-f", "{{ .NetworkSettings.IPAddress }}", args.containerId],
            (err, stdout) => {
                if (err) reject(err);
                else resolve(stdout.trim());
            },
        );
    });
}

/**
 * Detects whether the docker command is actually podman.
 * To do this, it looks for "podman" in the output of "docker --help".
 */
export function isPodman(): Promise<boolean> {
    return new Promise<boolean>((resolve, reject) => {
        childProcess.execFile("docker", ["--help"], (err, stdout) => {
            if (err) reject(err);
            else resolve(stdout.toLowerCase().includes("podman"));
        });
    });
}

/**
 * @type {Cypress.PluginConfig}
 */
export function docker(on: PluginEvents, config: PluginConfigOptions) {
    on("task", {
        dockerRun,
        dockerExec,
        dockerLogs,
        dockerStop,
        dockerRm,
        dockerIp,
    });
}