/*
 * Copyright (C) 2010 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

//#define LOG_NDEBUG 0
#define LOG_TAG "AmlMpEventLooperRoster"
#include <utils/AmlMpLog.h>
#include <string>
#include <unistd.h>

#include "AmlMpEventLooperRoster.h"

#include "AmlMpEventHandler.h"
#include "AmlMpMessage.h"

static const char* mName = LOG_TAG;

namespace aml_mp {

static bool verboseStats = false;

AmlMpEventLooperRoster::AmlMpEventLooperRoster()
    : mNextHandlerID(1) {
}

AmlMpEventLooper::handler_id AmlMpEventLooperRoster::registerHandler(
        const sptr<AmlMpEventLooper> &looper, const sptr<AmlMpEventHandler> &handler) {
    std::lock_guard<std::mutex> autoLock(mLock);

    if (handler->id() != 0) {
        MLOGE("A handler must only be registered once.");
        return -EINVAL;
    }

    HandlerInfo info;
    //coverity[var_deref_model]
    info.mLooper = looper;
    //coverity[var_deref_model]
    info.mHandler = handler;
    AmlMpEventLooper::handler_id handlerID = mNextHandlerID++;
    mHandlers.emplace(handlerID, info);

    handler->setID(handlerID, looper);

    return handlerID;
}

void AmlMpEventLooperRoster::unregisterHandler(AmlMpEventLooper::handler_id handlerID) {
    std::lock_guard<std::mutex> autoLock(mLock);

    auto index = mHandlers.find(handlerID);

    if (index == mHandlers.end()) {
        return;
    }

    const HandlerInfo &info = index->second;

    sptr<AmlMpEventHandler> handler = info.mHandler.promote();

    if (handler != NULL) {
        handler->setID(0, NULL);
    }

    mHandlers.erase(index);
}

void AmlMpEventLooperRoster::unregisterStaleHandlers() {

    std::vector<sptr<AmlMpEventLooper> > activeLoopers;
    {
        std::lock_guard<std::mutex> autoLock(mLock);

        for (auto it = mHandlers.begin(); it != mHandlers.end();) {
            const HandlerInfo &info = it->second;

            sptr<AmlMpEventLooper> looper = info.mLooper.promote();
            if (looper == NULL) {
                MLOGI("Unregistering stale handler:%d", it->first);
                it = mHandlers.erase(it);
            } else {
                // At this point 'looper' might be the only sp<> keeping
                // the object alive. To prevent it from going out of scope
                // and having ~ALooper call this method again recursively
                // and then deadlocking because of the Autolock above, add
                // it to a Vector which will go out of scope after the lock
                // has been released.
                activeLoopers.push_back(looper);
                ++it;
            }
        }
    }
}

#if 0
static void makeFourCC(uint32_t fourcc, char *s, size_t bufsz) {
    s[0] = (fourcc >> 24) & 0xff;
    if (s[0]) {
        s[1] = (fourcc >> 16) & 0xff;
        s[2] = (fourcc >> 8) & 0xff;
        s[3] = fourcc & 0xff;
        s[4] = 0;
    } else {
        snprintf(s, bufsz, "%u", fourcc);
    }
}
#endif

void AmlMpEventLooperRoster::dump(int fd, const std::vector<std::string>& args) {
    bool clear = false;
    bool oldVerbose = verboseStats;
    for (size_t i = 0; i < args.size(); i++) {
        if (args[i] == std::string("-c")) {
            clear = true;
        } else if (args[i] == std::string("-von")) {
            verboseStats = true;
        } else if (args[i] == std::string("-voff")) {
            verboseStats = false;
        }
    }
    std::string s;
    if (verboseStats && !oldVerbose) {
        s.append("(verbose stats collection enabled, stats will be cleared)\n");
    }

    std::lock_guard<std::mutex> autoLock(mLock);
    size_t n = mHandlers.size();
    //s.appendFormat(" %zu registered handlers:\n", n);

    for (size_t i = 0; i < n; i++) {
        //s.appendFormat("  %d: ", mHandlers.keyAt(i));
        HandlerInfo &info = mHandlers.at(i);
        sptr<AmlMpEventLooper> looper = info.mLooper.promote();
        if (looper != NULL) {
            s.append(looper->getName());
            sptr<AmlMpEventHandler> handler = info.mHandler.promote();
            if (handler != NULL) {
                handler->mVerboseStats = verboseStats;
                //s.appendFormat(": %u messages processed", handler->mMessageCounter);
                if (verboseStats) {
                    for (size_t j = 0; j < handler->mMessages.size(); j++) {
                        //char fourcc[15];
                        //makeFourCC(handler->mMessages.keyAt(j), fourcc, sizeof(fourcc));
                        //s.appendFormat("\n    %s: %u",
                                //fourcc,
                                //handler->mMessages.valueAt(j));
                    }
                } else {
                    handler->mMessages.clear();
                }
                if (clear || (verboseStats && !oldVerbose)) {
                    handler->mMessageCounter = 0;
                    handler->mMessages.clear();
                }
            } else {
                s.append(": <stale handler>");
            }
        } else {
            s.append("<stale>");
        }
        s.append("\n");
    }
    write(fd, s.c_str(), s.size());
}

}  // namespace aml_mp