#define GC_LINUX_THREADS 1
#include <gc/gc_allocator.h>

#include "json.hh"

#include "attr-path.hh"
#include "derivations.hh"

#include <sys/resource.h>
#include <nlohmann/json.hpp>

static Path gcRootsDir;
static size_t maxMemorySize;
struct MyArgs : MixEvalArgs, MixCommonArgs
{
    Path releaseExpr;
    bool flake = false;
    bool dryRun = false;

    MyArgs() : MixCommonArgs("hydra-eval-jobs")
    {
        mkFlag()
            .longName("help")
            .description("show usage information")
            .handler([&]() {
                printHelp(programName, std::cout);
                throw Exit();
            });

static Path gcRootsDir;

        mkFlag()
            .longName("gc-roots-dir")
            .description("garbage collector roots directory")
            .labels({"path"})
            .dest(&gcRootsDir);

        mkFlag()
            .longName("dry-run")
            .description("don't create store derivations")
            .set(&dryRun, true);

static void findJobs(EvalState & state, JSONObject & top,
    Bindings & autoArgs, Value & v, const string & attrPath);

        mkFlag()
            .longName("flake")
            .description("build a flake")
            .set(&flake, true);
        expectArg("expr", &releaseExpr);
    }
};

static MyArgs myArgs;

static string queryMetaStrings(EvalState & state, DrvInfo & drv, const string & name, const string & subAttribute)

static std::string queryMetaStrings(EvalState & state, DrvInfo & drv, const string & name, const string & subAttribute)

static void findJobsWrapped(EvalState & state, JSONObject & top,
    Bindings & autoArgs, Value & vIn, const string & attrPath)

static void worker(
    EvalState & state,
    Bindings & autoArgs,
    AutoCloseFD & to,
    AutoCloseFD & from)

    debug(format("at path `%1%'") % attrPath);

    Value vTop;

    checkInterrupt();

    if (myArgs.flake) {
        using namespace flake;

    Value v;
    state.autoCallFunction(autoArgs, vIn, v);

        auto flakeRef = parseFlakeRef(myArgs.releaseExpr);

    if (v.type == tAttrs) {

        auto vFlake = state.allocValue();

        auto drv = getDerivation(state, v, false);

        auto lockedFlake = lockFlake(state, flakeRef,
            LockFlags {
                .updateLockFile = false,
                .useRegistries = false,
                .allowMutable = false,
            });

        if (drv) {
            Path drvPath;

        callFlake(state, lockedFlake, *vFlake);

            DrvInfo::Outputs outputs = drv->queryOutputs();

        auto vOutputs = vFlake->attrs->get(state.symbols.create("outputs"))->value;
        state.forceValue(*vOutputs);
        auto aHydraJobs = vOutputs->attrs->get(state.symbols.create("hydraJobs"));
        if (!aHydraJobs)
            aHydraJobs = vOutputs->attrs->get(state.symbols.create("checks"));
        if (!aHydraJobs)
            throw Error("flake '%s' does not provide any Hydra jobs or checks", flakeRef);
        vTop = *aHydraJobs->value;
    } else {
        state.evalFile(lookupFileArg(state, myArgs.releaseExpr), vTop);
    }

            if (drv->querySystem() == "unknown")
                throw EvalError("derivation must have a ‘system’ attribute");

    auto vRoot = state.allocValue();
    state.autoCallFunction(autoArgs, vTop, *vRoot);

            {
            auto res = top.object(attrPath);
            res.attr("nixName", drv->queryName());
            res.attr("system", drv->querySystem());
            res.attr("drvPath", drvPath = drv->queryDrvPath());
            res.attr("description", drv->queryMetaString("description"));
            res.attr("license", queryMetaStrings(state, *drv, "license", "shortName"));
            res.attr("homepage", drv->queryMetaString("homepage"));
            res.attr("maintainers", queryMetaStrings(state, *drv, "maintainers", "email"));
            res.attr("schedulingPriority", drv->queryMetaInt("schedulingPriority", 100));
            res.attr("timeout", drv->queryMetaInt("timeout", 36000));
            res.attr("maxSilent", drv->queryMetaInt("maxSilent", 7200));
            res.attr("isChannel", drv->queryMetaBool("isHydraChannel", false));

    while (true) {
        /* Wait for the master to send us a job name. */
        writeLine(to.get(), "next");

            /* If this is an aggregate, then get its constituents. */
            Bindings::iterator a = v.attrs->find(state.symbols.create("_hydraAggregate"));
            if (a != v.attrs->end() && state.forceBool(*a->value, *a->pos)) {
                Bindings::iterator a = v.attrs->find(state.symbols.create("constituents"));
                if (a == v.attrs->end())
                    throw EvalError("derivation must have a ‘constituents’ attribute");
                PathSet context;
                state.coerceToString(*a->pos, *a->value, context, true, false);
                PathSet drvs;
                for (auto & i : context)
                    if (i.at(0) == '!') {
                        size_t index = i.find("!", 1);
                        drvs.insert(string(i, index + 1));

        auto s = readLine(from.get());
        if (s == "exit") break;
        if (!hasPrefix(s, "do ")) abort();
        std::string attrPath(s, 3);
        debug("worker process %d at '%s'", getpid(), attrPath);
        /* Evaluate it and send info back to the master. */
        nlohmann::json reply;
        try {
            auto v = findAlongAttrPath(state, attrPath, autoArgs, *vRoot).first;
            state.forceValue(*v);
            if (auto drv = getDerivation(state, *v, false)) {
                DrvInfo::Outputs outputs = drv->queryOutputs();
                if (drv->querySystem() == "unknown")
                    throw EvalError("derivation must have a 'system' attribute");
                auto drvPath = drv->queryDrvPath();
                nlohmann::json job;
                job["nixName"] = drv->queryName();
                job["system"] =drv->querySystem();
                job["drvPath"] = drvPath;
                job["description"] = drv->queryMetaString("description");
                job["license"] = queryMetaStrings(state, *drv, "license", "shortName");
                job["homepage"] = drv->queryMetaString("homepage");
                job["maintainers"] = queryMetaStrings(state, *drv, "maintainers", "email");
                job["schedulingPriority"] = drv->queryMetaInt("schedulingPriority", 100);
                job["timeout"] = drv->queryMetaInt("timeout", 36000);
                job["maxSilent"] = drv->queryMetaInt("maxSilent", 7200);
                job["isChannel"] = drv->queryMetaBool("isHydraChannel", false);
                /* If this is an aggregate, then get its constituents. */
                auto a = v->attrs->get(state.symbols.create("_hydraAggregate"));
                if (a && state.forceBool(*a->value, *a->pos)) {
                    auto a = v->attrs->get(state.symbols.create("constituents"));
                    if (!a)
                        throw EvalError("derivation must have a ‘constituents’ attribute");
                    PathSet context;
                    state.coerceToString(*a->pos, *a->value, context, true, false);
                    for (auto & i : context)
                        if (i.at(0) == '!') {
                            size_t index = i.find("!", 1);
                            job["constituents"].push_back(string(i, index + 1));
                        }
                    state.forceList(*a->value, *a->pos);
                    for (unsigned int n = 0; n < a->value->listSize(); ++n) {
                        auto v = a->value->listElems()[n];
                        state.forceValue(*v);
                        if (v->type == tString)
                            job["namedConstituents"].push_back(state.forceStringNoCtx(*v));

                res.attr("constituents", concatStringsSep(" ", drvs));
            }

                }

            /* Register the derivation as a GC root.  !!! This
               registers roots for jobs that we may have already
               done. */
            auto localStore = state.store.dynamic_pointer_cast<LocalFSStore>();
            if (gcRootsDir != "" && localStore) {
                Path root = gcRootsDir + "/" + std::string(baseNameOf(drvPath));
                if (!pathExists(root))
                    localStore->addPermRoot(localStore->parseStorePath(drvPath), root, false);
            }

                /* Register the derivation as a GC root.  !!! This
                   registers roots for jobs that we may have already
                   done. */
                auto localStore = state.store.dynamic_pointer_cast<LocalFSStore>();
                if (gcRootsDir != "" && localStore) {
                    Path root = gcRootsDir + "/" + std::string(baseNameOf(drvPath));
                    if (!pathExists(root))
                        localStore->addPermRoot(localStore->parseStorePath(drvPath), root, false);
                }

            auto res2 = res.object("outputs");
            for (auto & j : outputs)
                res2.attr(j.first, j.second);

                nlohmann::json out;
                for (auto & j : outputs)
                    out[j.first] = j.second;
                job["outputs"] = std::move(out);

                reply["job"] = std::move(job);

        }

        else {
            if (!state.isDerivation(v)) {
                for (auto & i : v.attrs->lexicographicOrder()) {

            else if (v->type == tAttrs) {
                auto attrs = nlohmann::json::array();
                StringSet ss;
                for (auto & i : v->attrs->lexicographicOrder()) {

                    /* Skip jobs with dots in the name. */
                    if (name.find('.') != std::string::npos) {

                    if (name.find('.') != std::string::npos || name.find(' ') != std::string::npos) {

                    findJobs(state, top, autoArgs, *i->value,
                        (attrPath.empty() ? "" : attrPath + ".") + name);

                    attrs.push_back(name);

                reply["attrs"] = std::move(attrs);

        } catch (EvalError & e) {
            reply["error"] = filterANSIEscapes(e.msg(), true);

    }

    else if (v.type == tNull) {
        // allow null values, meaning 'do nothing'
    }
    else
        throw TypeError(format("unsupported value: %1%") % v);
}

        writeLine(to.get(), reply.dump());

static void findJobs(EvalState & state, JSONObject & top,
    Bindings & autoArgs, Value & v, const string & attrPath)
{
    try {
        findJobsWrapped(state, top, autoArgs, v, attrPath);
    } catch (EvalError & e) {
        auto res = top.object(attrPath);
        res.attr("error", filterANSIEscapes(e.msg(), true));

        /* If our RSS exceeds the maximum, exit. The master will
           start a new process. */
        struct rusage r;
        getrusage(RUSAGE_SELF, &r);
        if ((size_t) r.ru_maxrss > maxMemorySize * 1024) break;

}

    writeLine(to.get(), "restart");
}

        auto initialHeapSize = config->getStrOption("evaluator_initial_heap_size", "");
        if (initialHeapSize != "")
            setenv("GC_INITIAL_HEAP_SIZE", initialHeapSize.c_str(), 1);

        auto nrWorkers = config->getIntOption("evaluator_workers", 1);
        maxMemorySize = config->getIntOption("evaluator_max_memory_size", 4096);

        struct MyArgs : MixEvalArgs, MixCommonArgs
        {
            Path releaseExpr;
            bool flake = false;
            MyArgs() : MixCommonArgs("hydra-eval-jobs")
            {
                mkFlag()
                    .longName("help")
                    .description("show usage information")
                    .handler([&]() {
                        printHelp(programName, std::cout);
                        throw Exit();
                    });

                mkFlag()
                    .longName("gc-roots-dir")
                    .description("garbage collector roots directory")
                    .labels({"path"})
                    .dest(&gcRootsDir);
                mkFlag()
                    .longName("dry-run")
                    .description("don't create store derivations")
                    .set(&settings.readOnlyMode, true);
                mkFlag()
                    .longName("flake")
                    .description("build a flake")
                    .set(&flake, true);
                expectArg("expr", &releaseExpr);
            }
        };
        MyArgs myArgs;

        JSONObject json(std::cout, true);
        std::cout.flush();

        if (myArgs.dryRun) settings.readOnlyMode = true;

        EvalState state(myArgs.searchPath, openStore());

        struct State
        {
            std::set<std::string> todo{""};
            std::set<std::string> active;
            nlohmann::json jobs;
            std::exception_ptr exc;
        };

        Bindings & autoArgs = *myArgs.getAutoArgs(state);

        std::condition_variable wakeup;

        Value v;

        Sync<State> state_;

        if (myArgs.flake) {
            using namespace flake;

        /* Start a handler thread per worker process. */
        auto handler = [&]()
        {
            try {
                pid_t pid = -1;
                AutoCloseFD from, to;

            auto flakeRef = parseFlakeRef(myArgs.releaseExpr);

                while (true) {

            auto vFlake = state.allocValue();

                    /* Start a new worker process if necessary. */
                    if (pid == -1) {
                        Pipe toPipe, fromPipe;
                        toPipe.create();
                        fromPipe.create();
                        pid = startProcess(
                            [&,
                             to{std::make_shared<AutoCloseFD>(std::move(fromPipe.writeSide))},
                             from{std::make_shared<AutoCloseFD>(std::move(toPipe.readSide))}
                            ]()
                            {
                                try {
                                    EvalState state(myArgs.searchPath, openStore());
                                    Bindings & autoArgs = *myArgs.getAutoArgs(state);
                                    worker(state, autoArgs, *to, *from);
                                } catch (std::exception & e) {
                                    nlohmann::json err;
                                    err["error"] = e.what();
                                    writeLine(to->get(), err.dump());
                                }
                            },
                            ProcessOptions { .allowVfork = false });
                        from = std::move(fromPipe.readSide);
                        to = std::move(toPipe.writeSide);
                        debug("created worker process %d", pid);
                    }

            auto lockedFlake = lockFlake(state, flakeRef,
                LockFlags {
                    .updateLockFile = false,
                    .useRegistries = false,
                    .allowMutable = false,
                });

                    /* Check whether the existing worker process is still there. */
                    auto s = readLine(from.get());
                    if (s == "restart") {
                        pid = -1;
                        continue;
                    } else if (s != "next") {
                        auto json = nlohmann::json::parse(s);
                        throw Error("worker error: %s", (std::string) json["error"]);
                    }

            callFlake(state, lockedFlake, *vFlake);

                    /* Wait for a job name to become available. */
                    std::string attrPath;

            auto vOutputs = (*vFlake->attrs->get(state.symbols.create("outputs")))->value;
            state.forceValue(*vOutputs);

                    while (true) {
                        checkInterrupt();
                        auto state(state_.lock());
                        if ((state->todo.empty() && state->active.empty()) || state->exc) {
                            writeLine(to.get(), "exit");
                            return;
                        }
                        if (!state->todo.empty()) {
                            attrPath = *state->todo.begin();
                            state->todo.erase(state->todo.begin());
                            state->active.insert(attrPath);
                            break;
                        } else
                            state.wait(wakeup);
                    }
                    /* Tell the worker to evaluate it. */
                    writeLine(to.get(), "do " + attrPath);
                    /* Wait for the response. */
                    auto response = nlohmann::json::parse(readLine(from.get()));
                    /* Handle the response. */
                    StringSet newAttrs;
                    if (response.find("job") != response.end()) {
                        auto state(state_.lock());
                        state->jobs[attrPath] = response["job"];
                    }

            auto aHydraJobs = vOutputs->attrs->get(state.symbols.create("hydraJobs"));
            if (!aHydraJobs)
                aHydraJobs = vOutputs->attrs->get(state.symbols.create("checks"));
            if (!aHydraJobs)
                throw Error("flake '%s' does not provide any Hydra jobs or checks", flakeRef);

                    if (response.find("attrs") != response.end()) {
                        for (auto & i : response["attrs"]) {
                            auto s = (attrPath.empty() ? "" : attrPath + ".") + (std::string) i;
                            newAttrs.insert(s);
                        }
                    }
                    if (response.find("error") != response.end()) {
                        auto state(state_.lock());
                        state->jobs[attrPath]["error"] = response["error"];
                    }

            v = *(*aHydraJobs)->value;

                    /* Add newly discovered job names to the queue. */
                    {
                        auto state(state_.lock());
                        state->active.erase(attrPath);
                        for (auto & s : newAttrs)
                            state->todo.insert(s);
                        wakeup.notify_all();
                    }
                }
            } catch (...) {
                auto state(state_.lock());
                state->exc = std::current_exception();
                wakeup.notify_all();
            }
        };

        } else {
            state.evalFile(lookupFileArg(state, myArgs.releaseExpr), v);

        std::vector<std::thread> threads;
        for (size_t i = 0; i < nrWorkers; i++)
            threads.emplace_back(std::thread(handler));
        for (auto & thread : threads)
            thread.join();
        auto state(state_.lock());
        if (state->exc)
            std::rethrow_exception(state->exc);
        /* For aggregate jobs that have named consistuents
           (i.e. constituents that are a job name rather than a
           derivation), look up the referenced job and add it to the
           dependencies of the aggregate derivation. */
        auto store = openStore();
        for (auto i = state->jobs.begin(); i != state->jobs.end(); ++i) {
            auto jobName = i.key();
            auto & job = i.value();
            auto named = job.find("namedConstituents");
            if (named == job.end()) continue;
            if (myArgs.dryRun) {
                for (std::string jobName2 : *named) {
                    auto job2 = state->jobs.find(jobName2);
                    if (job2 == state->jobs.end())
                        throw Error("aggregate job '%s' references non-existent job '%s'", jobName, jobName2);
                    std::string drvPath2 = (*job2)["drvPath"];
                    job["constituents"].push_back(drvPath2);
                }
            } else {
                std::string drvPath = job["drvPath"];
                auto drv = readDerivation(*store, drvPath);
                for (std::string jobName2 : *named) {
                    auto job2 = state->jobs.find(jobName2);
                    if (job2 == state->jobs.end())
                        throw Error("aggregate job '%s' references non-existent job '%s'", jobName, jobName2);
                    std::string drvPath2 = (*job2)["drvPath"];
                    auto drv2 = readDerivation(*store, drvPath2);
                    job["constituents"].push_back(drvPath2);
                    drv.inputDrvs[store->parseStorePath(drvPath2)] = {drv2.outputs.begin()->first};
                }
                std::string drvName(store->parseStorePath(drvPath).name());
                assert(hasSuffix(drvName, drvExtension));
                drvName.resize(drvName.size() - drvExtension.size());
                auto h = hashDerivationModulo(*store, drv, true);
                auto outPath = store->makeOutputPath("out", h, drvName);
                drv.env["out"] = store->printStorePath(outPath);
                drv.outputs.insert_or_assign("out", DerivationOutput(outPath.clone(), "", ""));
                auto newDrvPath = store->printStorePath(writeDerivation(store, drv, drvName));
                debug("rewrote aggregate derivation %s -> %s", drvPath, newDrvPath);
                job["drvPath"] = newDrvPath;
                job["outputs"]["out"] = store->printStorePath(outPath);
            }
            job.erase("namedConstituents");

        findJobs(state, json, autoArgs, v, "");

        std::cout << state->jobs.dump(2) << "\n";