#include <string.h>
#include <stdlib.h> // malloc
#include <assert.h> // assert
#include <stdio.h>  // printf
#include <sstream> // stringstream
#include <deque> // deque
#include <boost/algorithm/string.hpp> // trim

//#define SCXML_VERBOSE

#include "uscxml/config.h"

#ifdef APPLE
#include <mach/mach.h>
#include <mach/mach_time.h>
#include <pthread.h>
#endif

#ifndef AUTOINCLUDE_TEST
#include "test-c-machine.machine.c"
#endif

#include "uscxml/Convenience.h"
#include "uscxml/concurrency/Timer.h"
//#include "uscxml/DOMUtils.h"
#include "uscxml/Factory.h"
#include "uscxml/InterpreterInfo.h"
#include "uscxml/UUID.h"

#include "uscxml/concurrency/DelayedEventQueue.h"
#include "uscxml/concurrency/tinythread.h"

#ifdef BUILD_PROFILING
#   include "uscxml/plugins/DataModel.h"
# endif

#define USER_DATA(ctx) ((GenCInterpreterInfo*)(((scxml_ctx*)ctx)->user_data))

using namespace uscxml;

typedef struct scxml_foreach_info scxml_foreach_info;
struct scxml_foreach_info {
    size_t iterations;
    size_t currIteration;
};

class GenCInterpreterInfo : public InterpreterInfo {
public:
    NameSpaceInfo getNameSpaceInfo() const {
        return nsInfo;
    }
    const std::string& getName() {
        return name;
    }
    const std::string& getSessionId() {
        return sessionId;
    }
    const std::map<std::string, IOProcessor>& getIOProcessors() {
        return ioProcs;
    }
    bool isInState(const std::string& stateId) {
        for (int i = 0 ; i < SCXML_NUMBER_STATES; i++) {
            if (scxml_states[i].name != NULL && IS_SET(i, ctx->config) && stateId == scxml_states[i].name)
                return true;
        }
        return false;
    }
    Arabica::DOM::Document<std::string> getDocument() const {
        return document;
    }
    const std::map<std::string, Invoker>& getInvokers() {
        return invokers;
    }
    
    NameSpaceInfo nsInfo;
    std::string name;
    std::string sessionId;
    std::map<std::string, IOProcessor> ioProcs;
    std::map<std::string, Invoker> invokers;
    Arabica::DOM::Document<std::string> document;
    scxml_ctx* ctx;
    DataModel datamodel;
    
    std::map<const scxml_elem_foreach*, scxml_foreach_info*> foreachInfo;
    std::deque<Event*> iq;
    std::deque<Event*> eq;
    
    DelayedEventQueue delayQueue;
    std::map<std::string, SendRequest*> sendIds;

    tthread::condition_variable monitor;
    tthread::mutex mutex;
};

int matches(const char* desc, const char* event) {
    const char* dPtr = desc;
    const char* ePtr = event;
    while(*dPtr != 0) {

        if (*dPtr == '*' && *ePtr != 0) // something following
            return true;
        
        // descriptor differs from event name
        if (*dPtr != *ePtr) {
            // move to next descriptor
            while(*dPtr != ' ' && *dPtr != 0) {
                dPtr++;
            }
            if (*dPtr == 0)
                return false;
            dPtr++;
            ePtr = event;
        } else {
            // move both pointers one character
            dPtr++;
            ePtr++;

        }
        
        // descriptor is done, return match
        if (((*dPtr == 0 || *dPtr == ' ') && (*ePtr == 0 || *ePtr == ' ')) || // exact match, end of string
            (*dPtr == ' ' && *ePtr == '.') || (*dPtr == 0 && *ePtr == '.')) // prefix match
            return true;
    }
    return false;
}

int exec_content_raise(const scxml_ctx* ctx, const char* event) {
    Event* e = new Event();
    e->name = strdup(event);
    
    if (boost::starts_with(e->name, "error.")) {
        e->eventType = Event::PLATFORM;
    } else {
        e->eventType = Event::INTERNAL;
    }
    
#ifdef SCXML_VERBOSE
    printf("Raising Internal Event: %s\n", e->name.c_str());
#endif
    USER_DATA(ctx)->iq.push_back(e);
    return SCXML_ERR_OK;
}

int is_true(const scxml_ctx* ctx, const char* expr) {
    try {
        return USER_DATA(ctx)->datamodel.evalAsBool(expr);
    } catch (Event e) {
        exec_content_raise(ctx, e.name.c_str());
    }
    return false;
}

int is_enabled(const scxml_ctx* ctx, const scxml_transition* t, const void* e) {
    Event* event = (Event*)e;
    if (event == NULL) {
        if (t->event == NULL) {
            // spontaneous transition, null event
            if (t->condition != NULL)
                return is_true(ctx, t->condition);
            return true;
        } else {
            // spontaneous transition, but real event
            return false;
        }
    }

    // real transition, real event
    if (matches(t->event, event->name.c_str())) {
        if (t->condition != NULL)
            return is_true(ctx, t->condition);
        return true;
    }
    return false;
}

int raise_done_event(const scxml_ctx* ctx, const scxml_state* state, const scxml_elem_donedata* donedata) {
    Event* e = new Event();
    e->name = std::string("done.state.") + state->name;
    
    if (donedata) {
        if (donedata->content != NULL) {
            e->data = Data(donedata->content, Data::VERBATIM);
        } else if (donedata->contentexpr != NULL) {
            try {
                e->data = USER_DATA(ctx)->datamodel.getStringAsData(donedata->contentexpr);
            } catch (Event e) {
                exec_content_raise(ctx, e.name.c_str());
            }
        } else {
            try {
                const scxml_elem_param* param = donedata->params;
                while (param && ELEM_PARAM_IS_SET(param)) {
                    Data paramValue;
                    if (param->expr != NULL) {
                        paramValue = USER_DATA(ctx)->datamodel.getStringAsData(param->expr);
                    } else if(param->location) {
                        paramValue = USER_DATA(ctx)->datamodel.getStringAsData(param->location);
                    }
                    e->params.insert(std::make_pair(param->name, paramValue));
                    param++;
                }
            } catch (Event e) {
                exec_content_raise(ctx, e.name.c_str());
            }
        }
    }

#ifdef SCXML_VERBOSE
    printf("Raising Done Event: %s\n", e->name.c_str());
#endif
    USER_DATA(ctx)->iq.push_back(e);
    return SCXML_ERR_OK;
}

void delayedSend(void* ctx, std::string eventName) {
    tthread::lock_guard<tthread::mutex> lock(USER_DATA(ctx)->mutex);

    SendRequest* e = USER_DATA(ctx)->sendIds[eventName];
    if (e->target == "#_internal") {
        e->eventType = Event::INTERNAL;
#ifdef SCXML_VERBOSE
        printf("Pushing Internal Event: %s\n", e->name.c_str());
#endif
        USER_DATA(ctx)->iq.push_back(e);
    } else {
        e->eventType = Event::EXTERNAL;
#ifdef SCXML_VERBOSE
        printf("Pushing External Event: %s\n", e->name.c_str());
#endif
        USER_DATA(ctx)->eq.push_back(e);
    }
    USER_DATA(ctx)->monitor.notify_all();
}

int exec_content_cancel(const scxml_ctx* ctx, const char* sendid, const char* sendidexpr) {
    std::string eventId;
    if (sendid != NULL) {
        eventId = sendid;
    } else if (sendidexpr != NULL) {
        eventId = USER_DATA(ctx)->datamodel.evalAsString(sendidexpr);
    }
    
    if (eventId.length() > 0) {
        USER_DATA(ctx)->delayQueue.cancelEvent(eventId);
    } else {
        exec_content_raise(ctx, "error.execution");
        return SCXML_ERR_EXEC_CONTENT;
    }
    return SCXML_ERR_OK;
}

std::string spaceNormalize(const std::string& text) {
    std::stringstream content;
    std::string seperator;
    
    size_t start = 0;
    for (int i = 0; i < text.size(); i++) {
        if (isspace(text[i])) {
            if (i > 0 && start < i) {
                content << seperator << text.substr(start, i - start);
                seperator = " ";
            }
            while(isspace(text[++i])); // skip whitespaces
            start = i;
        } else if (i + 1 == text.size()) {
            content << seperator << text.substr(start, i + 1 - start);
        }
    }
    return content.str();
}


int exec_content_send(const scxml_ctx* ctx, const scxml_elem_send* send) {
    SendRequest* e = new SendRequest();
    
    std::string target;
    if (send->target != NULL) {
        e->target = send->target;
    } else if (send->targetexpr != NULL) {
        e->target = USER_DATA(ctx)->datamodel.evalAsString(send->targetexpr);
    } else {
        e->target = "#_external";
    }
    
    if (e->target.size() > 0 && (e->target[0] != '#' || e->target[1] != '_')) {
        delete e;
        exec_content_raise(ctx, "error.execution");
        return SCXML_ERR_INVALID_TARGET;
    }
    
    e->origintype = "http://www.w3.org/TR/scxml/#SCXMLEventProcessor";
    e->origin = e->target;

    try {
        if (send->type != NULL) {
            e->type = send->type;
        } else if (send->typeexpr != NULL) {
            e->type = USER_DATA(ctx)->datamodel.evalAsString(send->typeexpr);
        } else {
            e->type = "http://www.w3.org/TR/scxml/#SCXMLEventProcessor";
        }
    } catch (Event e) {
        exec_content_raise(ctx, e.name.c_str());
        return SCXML_ERR_EXEC_CONTENT;
    }
    
    // only one somewhat supported
    if (e->type != "http://www.w3.org/TR/scxml/#SCXMLEventProcessor") {
        delete e;
        exec_content_raise(ctx, "error.execution");
        return SCXML_ERR_INVALID_TARGET;
    }
    
    e->origintype = e->type;
    
    if (send->eventexpr != NULL) {
        e->name = USER_DATA(ctx)->datamodel.evalAsString(send->eventexpr);
    } else {
        e->name = strdup(send->event);
    }
    
    try {
        const scxml_elem_param* param = send->params;
        while (param && ELEM_PARAM_IS_SET(param)) {
            Data paramValue;
            if (param->expr != NULL) {
                paramValue = USER_DATA(ctx)->datamodel.getStringAsData(param->expr);
            } else if(param->location) {
                paramValue = USER_DATA(ctx)->datamodel.getStringAsData(param->location);
            }
            e->params.insert(std::make_pair(param->name, paramValue));
            param++;
        }
    } catch (Event e) {
        exec_content_raise(ctx, e.name.c_str());
        return SCXML_ERR_EXEC_CONTENT;
    }

    try {
        if (send->namelist != NULL) {
            const char* bPtr = &send->namelist[0];
            const char* ePtr = bPtr;
            while(*ePtr != '\0') {
                ePtr++;
                if (*ePtr == ' ' || *ePtr == '\0') {
                    std::string key(bPtr, ePtr - bPtr);
                    e->params.insert(std::make_pair(key, USER_DATA(ctx)->datamodel.getStringAsData(key)));
                    if (*ePtr == '\0')
                        break;
                    bPtr = ++ePtr;
                }
            }
        }
    } catch (Event e) {
        exec_content_raise(ctx, e.name.c_str());
        return SCXML_ERR_EXEC_CONTENT;
    }

    if (send->content != NULL) {
        // will it parse as json?
        Data d = Data::fromJSON(send->content);
        if (!d.empty()) {
            e->data = d;
        } else {
            e->data = Data(spaceNormalize(send->content), Data::VERBATIM);
        }
    }
    
    const char* sendid = NULL;
    if (send->id != NULL) {
        sendid = send->id;
        e->sendid = sendid;
    } else {
        sendid = strdup(UUID::getUUID().c_str());
        if (send->idlocation != NULL) {
            USER_DATA(ctx)->datamodel.assign(send->idlocation, Data(sendid, Data::VERBATIM));
        } else {
            e->hideSendId = true;
        }
    }
    
    
    size_t delayMs = 0;
    std::string delay;
    if (send->delayexpr != NULL) {
        delay = USER_DATA(ctx)->datamodel.evalAsString(send->delayexpr);
    } else if (send->delay != NULL) {
        delay = send->delay;
    }
    if (delay.size() > 0) {
        boost::trim(delay);
        
        NumAttr delayAttr(delay);
        if (iequals(delayAttr.unit, "ms")) {
            delayMs = strTo<uint32_t>(delayAttr.value);
        } else if (iequals(delayAttr.unit, "s")) {
            delayMs = strTo<double>(delayAttr.value) * 1000;
        } else if (delayAttr.unit.length() == 0) { // unit less delay is interpreted as milliseconds
            delayMs = strTo<uint32_t>(delayAttr.value);
        } else {
            std::cerr << "Cannot make sense of delay value " << delay << ": does not end in 's' or 'ms'";
        }
    }
    
    USER_DATA(ctx)->sendIds[sendid] = e;
    if (delayMs > 0) {
        USER_DATA(ctx)->delayQueue.addEvent(sendid, delayedSend, delayMs, (void*)ctx);
    } else {
        delayedSend((void*)ctx, sendid);
    }
    
    return SCXML_ERR_OK;
}

int exec_content_init(const scxml_ctx* ctx, const scxml_elem_data* data) {
    while(ELEM_DATA_IS_SET(data)) {
        Data d;
        if (data->expr != NULL) {
            d = Data(data->expr, Data::INTERPRETED);
        } else if (data->content != NULL) {
            d = Data(data->content, Data::INTERPRETED);
        } else {
            d = Data("undefined", Data::INTERPRETED);
        }
        try {
            USER_DATA(ctx)->datamodel.init(data->id, d);
        } catch (Event e) {
            exec_content_raise(ctx, e.name.c_str());
        }
        data++;
    }
    return SCXML_ERR_OK;
}

int exec_content_assign(const scxml_ctx* ctx, const char* location, const char* expr) {
    std::string key = location;
    if (key == "_sessionid" || key == "_name" || key == "_ioprocessors" || key == "_invokers" || key == "_event") {
        exec_content_raise(ctx, "error.execution");
        return SCXML_ERR_EXEC_CONTENT;
    }

    try {
        Data d(expr, Data::INTERPRETED);
        USER_DATA(ctx)->datamodel.assign(key, d);
    } catch (Event e) {
        exec_content_raise(ctx, e.name.c_str());
        return SCXML_ERR_EXEC_CONTENT;
    }
    return SCXML_ERR_OK;
}

int exec_content_foreach_init(const scxml_ctx* ctx, const scxml_elem_foreach* foreach) {
    try {
        scxml_foreach_info* feInfo = (scxml_foreach_info*)malloc(sizeof(scxml_foreach_info));
        USER_DATA(ctx)->foreachInfo[foreach] = feInfo;
        
        feInfo->iterations = USER_DATA(ctx)->datamodel.getLength(foreach->array);
        feInfo->currIteration = 0;
    } catch (Event e) {
        exec_content_raise(ctx, e.name.c_str());
        return SCXML_ERR_EXEC_CONTENT;
    }
    return SCXML_ERR_OK;
}

int exec_content_foreach_next(const scxml_ctx* ctx, const scxml_elem_foreach* foreach) {
    try {
        scxml_foreach_info* feInfo = USER_DATA(ctx)->foreachInfo[foreach];
        if (feInfo->currIteration < feInfo->iterations) {
            USER_DATA(ctx)->datamodel.setForeach((foreach->item != NULL ? foreach->item : ""),
                                                  (foreach->array != NULL ? foreach->array : ""),
                                                  (foreach->index != NULL ? foreach->index : ""),
                                                  feInfo->currIteration);
            feInfo->currIteration++;
            return SCXML_ERR_OK;
        }
    } catch (Event e) {
        exec_content_raise(ctx, e.name.c_str());
        free(USER_DATA(ctx)->foreachInfo[foreach]);
        USER_DATA(ctx)->foreachInfo.erase(foreach);
        return SCXML_ERR_EXEC_CONTENT;
    }
    return SCXML_ERR_FOREACH_DONE;
}

int exec_content_foreach_done(const scxml_ctx* ctx, const scxml_elem_foreach* foreach) {
    free(USER_DATA(ctx)->foreachInfo[foreach]);
    USER_DATA(ctx)->foreachInfo.erase(foreach);
    return SCXML_ERR_OK;
}

int exec_content_log(const scxml_ctx* ctx, const char* label, const char* expr) {
    try {
        if (label != 0) {
//            printf("%s: %s\n", label, USER_DATA(ctx)->datamodel.evalAsString(expr).c_str());
        } else {
//            printf("%s\n", USER_DATA(ctx)->datamodel.evalAsString(expr).c_str());
        }
    } catch (Event e) {
        exec_content_raise(ctx, e.name.c_str());
        return SCXML_ERR_EXEC_CONTENT;
    }
    
    return SCXML_ERR_OK;
}

int exec_content_script(const scxml_ctx* ctx, const char* src, const char* content) {
    if (content != NULL) {
        USER_DATA(ctx)->datamodel.eval(Arabica::DOM::Element<std::string>(), content);
    } else if (src != NULL) {
        return SCXML_ERR_UNSUPPORTED;
    }
    return SCXML_ERR_OK;
}

void* dequeue_external(const scxml_ctx* ctx) {
    tthread::lock_guard<tthread::mutex> lock(USER_DATA(ctx)->mutex);
    while (USER_DATA(ctx)->eq.size() == 0) {
        USER_DATA(ctx)->monitor.wait(USER_DATA(ctx)->mutex);
    }
    Event* e = USER_DATA(ctx)->eq.front();
    USER_DATA(ctx)->eq.pop_front();
    USER_DATA(ctx)->datamodel.setEvent(*e);
#ifdef SCXML_VERBOSE
    printf("Popping External Event: %s\n", e->name.c_str());
#endif
    return e;
}

void* dequeue_internal(const scxml_ctx* ctx) {
    if (USER_DATA(ctx)->iq.size() == 0)
        return NULL;
    Event* e = USER_DATA(ctx)->iq.front();
    USER_DATA(ctx)->iq.pop_front();
    USER_DATA(ctx)->datamodel.setEvent(*e);
#ifdef SCXML_VERBOSE
    printf("Popping Internal Event: %s\n", e->name.c_str());
#endif
    return e;
}

int main(int argc, char** argv) {
    
#ifdef APPLE
    mach_timebase_info_data_t timebase_info;
    mach_timebase_info(&timebase_info);

    const uint64_t NANOS_PER_MSEC = 1000000ULL;
    double clock2abs = ((double)timebase_info.denom / (double)timebase_info.numer) * NANOS_PER_MSEC;

    thread_time_constraint_policy_data_t policy;
    policy.period      = 0;
    policy.computation = (uint32_t)(5 * clock2abs); // 5 ms of work
    policy.constraint  = (uint32_t)(10 * clock2abs);
    policy.preemptible = FALSE;

    int kr = thread_policy_set(pthread_mach_thread_np(pthread_self()),
                               THREAD_TIME_CONSTRAINT_POLICY,
                               (thread_policy_t)&policy,
                               THREAD_TIME_CONSTRAINT_POLICY_COUNT);
    if (kr != KERN_SUCCESS) {
        mach_error("thread_policy_set:", kr);
        exit(1);
    }
#endif
    
    int err;
    size_t benchmarkRuns = 1;
    const char* envBenchmarkRuns = getenv("USCXML_BENCHMARK_ITERATIONS");
    if (envBenchmarkRuns != NULL) {
        benchmarkRuns = strTo<size_t>(envBenchmarkRuns);
    }

    
    size_t remainingRuns = benchmarkRuns;

    // setup info object required for datamodel
    GenCInterpreterInfo interpreterInfo;
    interpreterInfo.name = SCXML_MACHINE_NAME;
    interpreterInfo.sessionId = "rfwef";
    interpreterInfo.delayQueue.start();
    
    scxml_ctx ctx;
    interpreterInfo.ctx = &ctx;

    double avg = 0;
    size_t microSteps = 0;
#ifdef BUILD_PROFILING
    double avgDm = 0;
#endif

    while(remainingRuns-- > 0) {
        memset(&ctx, 0, sizeof(scxml_ctx));

        // fresh dm (expensive :( )
        interpreterInfo.datamodel = Factory::getInstance()->createDataModel("ecmascript", &interpreterInfo);

        // set info object as user data
        ctx.user_data = (void*)&interpreterInfo;
        
        // register callbacks with scxml context
        ctx.is_enabled = &is_enabled;
        ctx.is_true = &is_true;
        ctx.raise_done_event = &raise_done_event;
        
        ctx.exec_content_send = &exec_content_send;
        ctx.exec_content_raise = &exec_content_raise;
        ctx.exec_content_cancel = &exec_content_cancel;
        ctx.exec_content_log = &exec_content_log;
        ctx.exec_content_assign = &exec_content_assign;
        ctx.exec_content_foreach_init = &exec_content_foreach_init;
        ctx.exec_content_foreach_next = &exec_content_foreach_next;
        ctx.exec_content_foreach_done = &exec_content_foreach_done;
        ctx.dequeue_external = &dequeue_external;
        ctx.dequeue_internal = &dequeue_internal;
        ctx.exec_content_init = &exec_content_init;
        ctx.exec_content_script = &exec_content_script;
        
        Timer t;
        t.start();

        microSteps = 0;
        while((err = scxml_step(&ctx)) == SCXML_ERR_OK) { microSteps++; }
        assert(ctx.flags & SCXML_CTX_TOP_LEVEL_FINAL);
        
        t.stop();
        avg += t.elapsed;
#ifdef BUILD_PROFILING
        avgDm += interpreterInfo.datamodel.timer.elapsed;
        interpreterInfo.datamodel.timer.elapsed = 0;
#endif
        size_t passIdx = 0;
        for (int i = 0; i < SCXML_NUMBER_STATES; i++) {
            if (scxml_states[i].name && strcmp(scxml_states[i].name, "pass") == 0) {
                passIdx = i;
                break;
            }
        }

        assert(IS_SET(passIdx, ctx.config));
        interpreterInfo.delayQueue.cancelAllEvents();
        interpreterInfo.eq.clear();
        interpreterInfo.iq.clear();
    }
    
    // 14.25311111 us per microstep
    // 1.923466667 us
    std::cout << (avg * 1000.0) / (double)benchmarkRuns << " ms on average" << std::endl;
    std::cout << microSteps << " microsteps per iteration (" << (avg * 1000.0) / ((double)benchmarkRuns * (double)microSteps) << " ms per microstep)" << std::endl;
#ifdef BUILD_PROFILING
    std::cout << (avgDm * 1000.0) / (double)benchmarkRuns << " ms in datamodel" << std::endl;
    std::cout << ((avg - avgDm) * 1000.0) / ((double)benchmarkRuns * (double)microSteps) << " ms per microstep \\wo datamodel" << std::endl;
#endif
    interpreterInfo.delayQueue.stop();
    tthread::this_thread::sleep_for(tthread::chrono::milliseconds(100));
    return EXIT_SUCCESS;
}