const fs = require("fs");
const path = require("path");
const { execFileSync } = require("child_process");

function now() {
    return new Date().toISOString();
}

function verifyChecksum(filePath, checksum) {
    if (!checksum) {
        return;
    }
    const [alg, expected] = checksum.split(":", 2);
    if (!alg || !expected) {
        return;
    }
    const crypto = require("crypto");
    const actual = crypto.createHash(alg).update(fs.readFileSync(filePath)).digest("hex");
    if (actual !== expected) {
        throw new Error(`文件校验失败 ${filePath}`);
    }
}

function unpackArtifact(artifact, localPath, versionDir) {
    if (artifact.type !== "archive" || !artifact.unpack) {
        return;
    }

    const extractDir = path.resolve(path.dirname(localPath), "_extracted");
    fs.mkdirSync(extractDir, { recursive: true });
    const format = artifact.archive_format || "zip";
    if (format === "zip") {
        if (process.platform === "win32") {
            const source = localPath.replace(/'/g, "''");
            const target = extractDir.replace(/'/g, "''");
            execFileSync("powershell.exe", ["-NoProfile", "-Command", `Expand-Archive -Path '${source}' -DestinationPath '${target}' -Force`], { stdio: "inherit" });
        } else {
            execFileSync("unzip", ["-o", localPath, "-d", extractDir], { stdio: "inherit" });
        }
    } else if (["tar", "tar.gz", "tgz", "tar.xz"].includes(format)) {
        execFileSync("tar", ["-xf", localPath, "-C", extractDir], { stdio: "inherit" });
    }

    artifact.extracted_path = path.relative(versionDir, extractDir).replace(/\\/g, "/");
    if (artifact.entry_point) {
        artifact.extracted_entry_point = path.posix.join(artifact.extracted_path, artifact.entry_point.replace(/\\/g, "/"));
    }
}

module.exports = async function install(remote, id) {
    const parsed = remote.parseProjectVersion(id || "kit");
    const projectId = parsed.projectId;
    const group = parsed.group || "/modules";
    const project = await remote.getProjectMetadata(projectId, group);
    const version = parsed.version || project.version;
    if (!version) {
        throw new Error(`远程模块没有可安装版本 ${projectId}`);
    }

    const versionMeta = await remote.getVersionMetadata(projectId, version, project.group || group);
    const artifacts = remote.getMatchingArtifacts(versionMeta);
    if (artifacts.length < 1) {
        throw new Error(`没有匹配当前平台的文件 ${projectId}@${version}`);
    }

    const root = remote.getLocalModuleRoot(projectId);
    const versionDir = path.resolve(root, "versions", version);
    fs.mkdirSync(versionDir, { recursive: true });

    for (const artifact of artifacts) {
        const localPath = await remote.downloadArtifact(projectId, version, artifact, versionDir, project.group || group);
        verifyChecksum(localPath, artifact.checksum || (versionMeta.checksums && versionMeta.checksums[artifact.path]));
        unpackArtifact(artifact, localPath, versionDir);
    }

    const localVersionMeta = Object.assign({}, versionMeta, { installed_at: now(), artifacts });
    fs.writeFileSync(path.resolve(versionDir, ".version.json"), JSON.stringify(localVersionMeta, null, 4), "utf-8");

    const state = remote.getInstallState(projectId);
    const action = state.current_version ? "switch" : "install";
    await remote.activate(projectId, version, action);
    $logger.info(`当前版本 ${projectId}@${version}`);
    return version;
};