// testEngineJanet.c -- Janet on a context thread, driven the host way: register natives, open a
// context, fire-and-forget a script, and calogPump on the host thread. Verifies host-thread
// dispatch, the inline escape hatch, the cross-thread callback, aggregates both ways (array/table),
// a foreign function value, the error handler, and THREE concurrent VMs (Janet's thread-local
// janet_vm is the make-or-break gate for the actor model).

#define _POSIX_C_SOURCE 200809L

#include "calog.h"

#include <stdatomic.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>

#define CHECK(cond, msg) checkImpl((cond), (msg), __FILE__, __LINE__)

#define PUMP_LIMIT 4000

static CalogT          *calog         = NULL;
static _Atomic int64_t  reportedValue  = 0;
static _Atomic uint64_t reportedCtxId  = 0xFFFFu;
static _Atomic uint64_t inlineCtxId    = 0xFFFFu;
static _Atomic int32_t  bumpCount      = 0;
static _Atomic bool     scriptDone     = false;
static _Atomic int32_t  errorCount     = 0;
static _Atomic uint64_t errorCtxId     = 0;
static CalogFnT *_Atomic storedCb       = NULL;
static char              storedName[32] = { 0 };
static _Atomic int32_t   nameLen         = -1;
static int32_t          testsRun       = 0;
static int32_t          testsFailed    = 0;

static void    checkImpl(bool condition, const char *message, const char *file, int32_t line);
static int32_t nativeAdd(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t nativeBump(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t nativeDone(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t nativeGetAdder(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t nativeMakeUser(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t nativeMapAge(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t nativeReport(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t nativeReportInline(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t nativeReportName(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t nativeSetCb(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static void    onError(uint64_t contextId, const char *message, void *userData);
static void    pumpUntilDone(void);
static void    testConcurrentContexts(void);
static void    testCrossThreadCallback(void);
static void    testForeignFunction(void);
static void    testHostAndInlineNatives(void);
static void    testMapIngress(void);
static void    testMaterializedRecord(void);
static void    testScriptError(void);


static void checkImpl(bool condition, const char *message, const char *file, int32_t line) {
    testsRun++;
    if (!condition) {
        testsFailed++;
        printf("FAIL %s:%d  %s\n", file, line, message);
    }
}


static int32_t nativeAdd(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
    (void)userData;
    calogValueNil(result);
    if (argCount != 2 || args[0].type != calogIntE || args[1].type != calogIntE) {
        return calogFail(result, calogErrArgE, "add expects two integers");
    }
    calogValueInt(result, args[0].as.i + args[1].as.i);
    return calogOkE;
}


static int32_t nativeBump(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
    (void)args;
    (void)argCount;
    (void)userData;
    atomic_fetch_add(&bumpCount, 1);
    calogValueNil(result);
    return calogOkE;
}


static int32_t nativeDone(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
    (void)args;
    (void)argCount;
    (void)userData;
    atomic_store(&scriptDone, true);
    calogValueNil(result);
    return calogOkE;
}


static int32_t nativeGetAdder(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
    CalogFnT *callable;
    int32_t   status;

    (void)args;
    (void)argCount;
    (void)userData;
    calogValueNil(result);
    status = calogFnFromNative(&callable, calog, nativeAdd, NULL);
    if (status != calogOkE) {
        return calogFail(result, status, "getAdder could not allocate");
    }
    calogValueFn(result, callable);
    return calogOkE;
}


static int32_t nativeMakeUser(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
    CalogAggT  *user;
    CalogValueT key;
    CalogValueT val;
    int32_t     status;

    (void)args;
    (void)argCount;
    (void)userData;
    calogValueNil(result);
    status = calogAggCreate(&user, calogMapE);
    if (status != calogOkE) {
        return calogFail(result, status, "makeUser could not allocate");
    }
    calogValueString(&key, "name", 4);
    calogValueString(&val, "ada", 3);
    calogAggSet(user, &key, &val);
    calogValueString(&key, "age", 3);
    calogValueInt(&val, 36);
    calogAggSet(user, &key, &val);
    calogValueAgg(result, user);
    return calogOkE;
}


static int32_t nativeMapAge(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
    CalogValueT  key;
    CalogValueT *found;

    (void)userData;
    calogValueNil(result);
    if (argCount != 1 || args[0].type != calogAggE) {
        return calogFail(result, calogErrArgE, "mapAge expects a map");
    }
    calogValueString(&key, "age", 3);
    found = calogAggGet(args[0].as.agg, &key);
    calogValueFree(&key);
    if (found != NULL && found->type == calogIntE) {
        atomic_store(&reportedValue, found->as.i);
    }
    return calogOkE;
}


static int32_t nativeReport(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
    (void)userData;
    calogValueNil(result);
    if (argCount != 1 || args[0].type != calogIntE) {
        return calogFail(result, calogErrArgE, "report expects one integer");
    }
    atomic_store(&reportedCtxId, calogCurrentId());
    atomic_store(&reportedValue, args[0].as.i);
    return calogOkE;
}


static int32_t nativeReportInline(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
    (void)args;
    (void)argCount;
    (void)userData;
    atomic_store(&inlineCtxId, calogCurrentId());
    calogValueNil(result);
    return calogOkE;
}


static int32_t nativeReportName(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
    size_t length;

    (void)userData;
    calogValueNil(result);
    if (argCount != 1 || args[0].type != calogStringE) {
        return calogFail(result, calogErrArgE, "reportName expects one string");
    }
    length = (size_t)args[0].as.s.length;
    if (length >= sizeof(storedName)) {
        length = sizeof(storedName) - 1;
    }
    memcpy(storedName, args[0].as.s.bytes, length);
    storedName[length] = '\0';
    atomic_store(&nameLen, (int32_t)length);
    return calogOkE;
}


static int32_t nativeSetCb(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
    (void)userData;
    calogValueNil(result);
    if (argCount != 1 || args[0].type != calogFnE) {
        return calogFail(result, calogErrArgE, "setCb expects one function");
    }
    calogFnRetain(args[0].as.fn);
    atomic_store(&storedCb, args[0].as.fn);
    return calogOkE;
}


static void onError(uint64_t contextId, const char *message, void *userData) {
    (void)message;
    (void)userData;
    atomic_store(&errorCtxId, contextId);
    atomic_fetch_add(&errorCount, 1);
}


static void pumpUntilDone(void) {
    struct timespec ts = { 0, 500000 };
    int             errorsBefore;
    int             i;

    errorsBefore = atomic_load(&errorCount);
    for (i = 0; i < PUMP_LIMIT; i++) {
        calogPump(calog);
        if (atomic_load(&scriptDone) || atomic_load(&errorCount) != errorsBefore) {
            calogPump(calog);
            return;
        }
        nanosleep(&ts, NULL);
    }
}


static void testHostAndInlineNatives(void) {
    CalogContextT *ctx;

    ctx = calogContextOpen(calog, &calogJanetEngine);
    CHECK(ctx != NULL, "opened a Janet context");

    atomic_store(&scriptDone, false);
    calogContextEval(ctx, "(report 42) (reportInline 1) (done)");
    pumpUntilDone();

    CHECK(atomic_load(&reportedValue) == 42, "host native received the argument");
    CHECK(atomic_load(&reportedCtxId) == 0, "default native ran on the host thread (id 0)");
    CHECK(atomic_load(&inlineCtxId) == calogContextId(ctx), "inline native ran on the script's own thread");

    calogContextClose(ctx);
}


static void testMaterializedRecord(void) {
    CalogContextT *ctx;

    ctx = calogContextOpen(calog, &calogJanetEngine);
    atomic_store(&scriptDone, false);
    atomic_store(&nameLen, -1);
    atomic_store(&reportedValue, 0);
    calogContextEval(ctx, "(def u (makeUser)) (report (get u \"age\")) (reportName (get u \"name\")) (done)");
    pumpUntilDone();

    CHECK(atomic_load(&reportedValue) == 36, "read an int field from a materialized record table");
    CHECK(atomic_load(&nameLen) == 3 && memcmp(storedName, "ada", 3) == 0, "read a string field from a materialized record table");

    calogContextClose(ctx);
}


static void testMapIngress(void) {
    CalogContextT *ctx;

    ctx = calogContextOpen(calog, &calogJanetEngine);
    atomic_store(&scriptDone, false);
    atomic_store(&reportedValue, 0);
    // The script builds a table (with a nested array, exercising array ingress too) and hands it
    // to a native, which reads a field.
    calogContextEval(ctx, "(def m @{\"age\" 9 \"tags\" @[1 2]}) (mapAge m) (done)");
    pumpUntilDone();

    CHECK(atomic_load(&reportedValue) == 9, "native read a field from a table the script built");

    calogContextClose(ctx);
}


static void testForeignFunction(void) {
    CalogContextT *ctx;

    ctx = calogContextOpen(calog, &calogJanetEngine);
    atomic_store(&scriptDone, false);
    atomic_store(&reportedValue, 0);
    // getAdder returns a function value (a callable abstract); the script calls it as (adder 2 3).
    calogContextEval(ctx, "(def adder (getAdder)) (report (adder 2 3)) (done)");
    pumpUntilDone();

    CHECK(atomic_load(&reportedValue) == 5, "script called a foreign function value pushed in from the host");

    calogContextClose(ctx);
}


static void testCrossThreadCallback(void) {
    CalogContextT *ctx;
    CalogFnT      *callback;
    CalogValueT    arg;
    CalogValueT    result;
    int32_t        status;

    ctx = calogContextOpen(calog, &calogJanetEngine);
    atomic_store(&scriptDone, false);
    atomic_store(&storedCb, NULL);
    // A Janet function handed to setCb marshals to a CalogFnT (the function is gc-rooted).
    calogContextEval(ctx, "(defn cb [x] (+ x 100)) (setCb cb) (done)");
    pumpUntilDone();

    callback = atomic_load(&storedCb);
    CHECK(callback != NULL, "a Janet function was captured as a CalogFnT");

    calogValueInt(&arg, 7);
    status = calogFnInvoke(callback, &arg, 1, &result);
    CHECK(status == calogOkE && result.type == calogIntE && result.as.i == 107, "cross-thread callable invoke routed to the owner");
    calogValueFree(&result);
    calogValueFree(&arg);
    calogFnRelease(callback);

    calogContextClose(ctx);
}


static void testScriptError(void) {
    CalogContextT *ctx;
    int32_t        before;

    ctx    = calogContextOpen(calog, &calogJanetEngine);
    before = atomic_load(&errorCount);
    atomic_store(&scriptDone, false);
    calogContextEval(ctx, "(error \"intentional test error\")");
    pumpUntilDone();

    CHECK(atomic_load(&errorCount) == before + 1, "a fire-and-forget script error reached the error handler");
    CHECK(atomic_load(&errorCtxId) == calogContextId(ctx), "the error names the failing context");

    calogContextClose(ctx);
}


static void testConcurrentContexts(void) {
    CalogContextT  *ctxs[3];
    struct timespec ts = { 0, 500000 };
    int32_t         i;

    atomic_store(&bumpCount, 0);
    for (i = 0; i < 3; i++) {
        ctxs[i] = calogContextOpen(calog, &calogJanetEngine);
        calogContextEval(ctxs[i], "(bump) (bump) (bump)");
    }
    for (i = 0; i < PUMP_LIMIT && atomic_load(&bumpCount) < 9; i++) {
        calogPump(calog);
        nanosleep(&ts, NULL);
    }
    CHECK(atomic_load(&bumpCount) == 9, "three concurrent Janet VMs (thread-local janet_vm) all dispatched to the host");
    for (i = 0; i < 3; i++) {
        calogContextClose(ctxs[i]);
    }
}


int main(void) {
    calog = calogCreate();
    if (calog == NULL) {
        printf("calog create failed\n");
        return 1;
    }
    calogSetErrorHandler(calog, onError, NULL);
    calogRegister(calog, "report", nativeReport, NULL);
    calogRegister(calog, "setCb", nativeSetCb, NULL);
    calogRegister(calog, "done", nativeDone, NULL);
    calogRegister(calog, "bump", nativeBump, NULL);
    calogRegister(calog, "makeUser", nativeMakeUser, NULL);
    calogRegister(calog, "reportName", nativeReportName, NULL);
    calogRegister(calog, "getAdder", nativeGetAdder, NULL);
    calogRegister(calog, "mapAge", nativeMapAge, NULL);
    calogRegisterInline(calog, "reportInline", nativeReportInline, NULL);

    testHostAndInlineNatives();
    testMaterializedRecord();
    testMapIngress();
    testForeignFunction();
    testCrossThreadCallback();
    testScriptError();
    testConcurrentContexts();

    calogDestroy(calog);

    printf("\n%d checks, %d failed\n", testsRun, testsFailed);
    fflush(stdout);
    if (testsFailed != 0) {
        return 1;
    }
    return 0;
}