import * as fs from "fs";

import * as path from "path";

import { type CodeQL } from "./codeql";

import { type Config } from "./config-utils";

import { Logger } from "./logging";

import { asyncSome, BuildMode } from "./util";

export type TracerConfig = {

env: { [key: string]: string };

};

export async function shouldEnableIndirectTracing(

codeql: CodeQL,

config: Config,

): Promise<boolean> {

// We don't need to trace build mode none, or languages which unconditionally don't need tracing.

if (config.buildMode === BuildMode.None) {

return false;

}

// If the CLI supports `trace-command` with a `--build-mode`, we'll use direct tracing instead of

// indirect tracing.

if (config.buildMode === BuildMode.Autobuild) {

return false;

}

// Otherwise, use direct tracing if any of the languages need to be traced.

return asyncSome(config.languages, (l) => codeql.isTracedLanguage(l));

}

/**

* Delete variables as specified by the end-tracing script

*

* WARNING: This does not _really_ end tracing, as the tracer will restore its

* critical environment variables and it'll still be active for all processes

* launched from this build step.

*

* However, it will stop tracing for all steps past the current build step.

*/

export async function endTracingForCluster(

codeql: CodeQL,

config: Config,

logger: Logger,

): Promise<void> {

if (!(await shouldEnableIndirectTracing(codeql, config))) return;

logger.info(

"Unsetting build tracing environment variables. Subsequent steps of this job will not be traced.",

);

const envVariablesFile = path.resolve(

config.dbLocation,

"temp/tracingEnvironment/end-tracing.json",

);

if (!fs.existsSync(envVariablesFile)) {

throw new Error(

`Environment file for ending tracing not found: ${envVariablesFile}`,

);

}

try {

const endTracingEnvVariables: Map<string, string | null> = JSON.parse(

fs.readFileSync(envVariablesFile, "utf8"),

);

for (const [key, value] of Object.entries(endTracingEnvVariables)) {

if (value !== null) {

process.env[key] = value;

} else {

delete process.env[key];

}

}

} catch (e) {

throw new Error(

`Failed to parse file containing end tracing environment variables: ${e}`,

);

}

}

async function getTracerConfigForCluster(

config: Config,

): Promise<TracerConfig> {

const tracingEnvVariables = JSON.parse(

fs.readFileSync(

path.resolve(

config.dbLocation,

"temp/tracingEnvironment/start-tracing.json",

),

"utf8",

),

);

return {

env: tracingEnvVariables,

};

}

export async function getCombinedTracerConfig(

codeql: CodeQL,

config: Config,

): Promise<TracerConfig | undefined> {

if (!(await shouldEnableIndirectTracing(codeql, config))) {

return undefined;

}

return await getTracerConfigForCluster(config);

}