/*
 * Copyright (C) 2015 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.
 */

#include <utils/Log.h>

#include <string>
#include <utils/compiler.h>

#ifdef ANDROID
#   include <android/log.h>
#   ifndef UTILS_LOG_TAG
#       define UTILS_LOG_TAG "Filament"
#   endif
#endif

#if (!UTILS_TINY_IO)
#   include <iostream>
#endif

namespace utils {

#if (UTILS_TINY_IO)
namespace io {

UTILS_DEFINE_TLS(ostream::Buffer) ostream::mData;

UTILS_NOINLINE
void ostream::Buffer::advance(ssize_t n) noexcept {
    if (n > 0) {
        size_t written = n < size ? size_t(n) : size;
        curr += written;
        size -= written;
    }
}

UTILS_NOINLINE
void ostream::Buffer::reset() noexcept {
    curr = mStorage;
    size = sizeof(mStorage);
}


const char* ostream::getFormat(ostream::type t) const noexcept {
    // TODO: handle oct and hex
    switch (t) {
        case type::SHORT:       return "%hd";
        case type::USHORT:      return "%hu";
        case type::INT:         return "%d";
        case type::UINT:        return "%u";
        case type::LONG:        return "%ld";
        case type::ULONG:       return "%lu";
        case type::LONG_LONG:   return "%lld";
        case type::ULONG_LONG:  return "%llu";
        case type::DOUBLE:      return "%f";
        case type::LONG_DOUBLE: return "%Lf";
    }
}

ostream& ostream::operator<<(short value) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, getFormat(type::SHORT), value));
    return *this;
}

ostream& ostream::operator<<(unsigned short value) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, getFormat(type::USHORT), value));
    return *this;
}

ostream& ostream::operator<<(int value) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, getFormat(type::INT), value));
    return *this;
}

ostream& ostream::operator<<(unsigned int value) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, getFormat(type::UINT), value));
    return *this;
}

ostream& ostream::operator<<(long value) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, getFormat(type::LONG), value));
    return *this;
}

ostream& ostream::operator<<(unsigned long value) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, getFormat(type::ULONG), value));
    return *this;
}

ostream& ostream::operator<<(long long value) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, getFormat(type::LONG_LONG), value));
    return *this;
}

ostream& ostream::operator<<(unsigned long long value) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, getFormat(type::ULONG_LONG), value));
    return *this;
}

ostream& ostream::operator<<(float value) noexcept {
    return operator<<((double)value);
}

ostream& ostream::operator<<(double value) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, getFormat(type::DOUBLE), value));
    return *this;
}

ostream& ostream::operator<<(long double value) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, getFormat(type::LONG_DOUBLE), value));
    return *this;
}

ostream& ostream::operator<<(bool value) noexcept {
    return operator<<((int)value);
}

ostream& ostream::operator<<(const char* string) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, "%s", string));
    return *this;
}

ostream& ostream::operator<<(const void* value) noexcept {
    Buffer& buf = getBuffer();
    buf.advance(snprintf(buf.curr, buf.size, "%p", value));
    return *this;
}

ostream& ostream::flush() noexcept {
    Buffer& buf = getBuffer();
#if ANDROID
    switch (mPriority) {
        case DEBUG:
            __android_log_write(ANDROID_LOG_DEBUG, UTILS_LOG_TAG, buf.get());
            break;
        case ERROR:
            __android_log_write(ANDROID_LOG_ERROR, UTILS_LOG_TAG, buf.get());
            break;
        case WARNING:
            __android_log_write(ANDROID_LOG_WARN, UTILS_LOG_TAG, buf.get());
            break;
        case INFO:
            __android_log_write(ANDROID_LOG_INFO, UTILS_LOG_TAG, buf.get());
            break;
    }
#else
    switch (mPriority) {
        case DEBUG:
        case WARNING:
        case INFO:
            fprintf(stdout, "%s", buf.get());
            break;
        case ERROR:
            fprintf(stderr, "%s", buf.get());
            break;
    }
#endif
    buf.reset();
    return *this;
}

ostream& ostream::hex() noexcept {
    return *this;
}

ostream& ostream::dec() noexcept {
    return *this;
}

static ostream cout(ostream::Priority::DEBUG);
static ostream cerr(ostream::Priority::ERROR);
static ostream cwarn(ostream::Priority::WARNING);
static ostream cinfo(ostream::Priority::INFO);

} // namespace io


Loggers slog = {
        io::cout,   // debug
        io::cerr,   // error
        io::cwarn,  // warning
        io::cinfo   // info
};

#else // UTILS_TINY_IO

#if ANDROID
static constexpr const size_t LOG_BUFFER_SIZE = 1024;

class AndroidStreamBuffer : public std::streambuf {
public:
    explicit AndroidStreamBuffer(android_LogPriority priority) {
        mPriority = priority;
        setp(mBuffer, mBuffer + LOG_BUFFER_SIZE - 1);
    }

private:
    int overflow(int c) {
        if (c != traits_type::eof()) {
            *pptr() = traits_type::to_char_type(c);
            pbump(1);
            if (sync() >= 0) {
                return c;
            }
        }

        return traits_type::eof();
    }

    int sync() {
        if (pbase() != pptr()) {
            char buffer[LOG_BUFFER_SIZE + 1];
            std::ptrdiff_t length = pptr() - pbase();
            memcpy(buffer, pbase(), length);
            buffer[length] = '\0';
            pbump(-length);

            __android_log_write(mPriority, UTILS_LOG_TAG, buffer);
        }
        return 0;
    }

    android_LogPriority mPriority;
    char mBuffer[LOG_BUFFER_SIZE];
};

static std::ostream android_cout(new AndroidStreamBuffer(ANDROID_LOG_DEBUG));
static std::ostream android_cerr(new AndroidStreamBuffer(ANDROID_LOG_ERROR));
static std::ostream android_cwarn(new AndroidStreamBuffer(ANDROID_LOG_WARN));
static std::ostream android_cinfo(new AndroidStreamBuffer(ANDROID_LOG_INFO));

Loggers slog = {
    android_cout,   // debug
    android_cerr,   // error
    android_cwarn,  // warning
    android_cinfo   // info
};

#else // ANDROID

Loggers slog = {
    std::cout,  // debug
    std::cerr,  // error
    std::cout,  // warning
    std::cout   // info
};

#endif

#endif // UTILS_TINY_IO

} // namespace utils