#include "Buffer.h"
#include "MemoryPool.h"
#include "LoopBuffer.h"
#include "Log.h"

using namespace base;

CBuffer::CBuffer(std::shared_ptr<CMemoryPool>& pool) :
    _buff_count(0),
    _buffer_read(nullptr),
    _buffer_write(nullptr),
    _buffer_end(nullptr),
    _pool(pool){

}

CBuffer::~CBuffer() {
    CLoopBuffer* temp = _buffer_read;
    while (temp) {
        _buffer_read = _buffer_read->GetNext();
        _pool->PoolDelete<CLoopBuffer>(temp);
        temp = _buffer_read;
    }
}

int CBuffer::ReadNotClear(char* res, int len) {
    if (!_buffer_read) {
        return 0;
    }

    std::unique_lock<std::mutex> lock(_mutex);
    CLoopBuffer* temp = _buffer_read;
    int cur_len = 0;
    while (temp && cur_len < len) {
        cur_len += temp->ReadNotClear(res, len - cur_len);
        if (temp == _buffer_write) {
            break;
        }
        temp = temp->GetNext();
    }
    return cur_len;
}

int CBuffer::Read(char* res, int len) {
    if (!_buffer_read) {
        return 0;
    }

    std::unique_lock<std::mutex> lock(_mutex);
    CLoopBuffer* temp = _buffer_read;
    CLoopBuffer* del_temp = nullptr;;
    int cur_len = 0;
    while (temp) {
        cur_len += temp->Read(res, len - cur_len);
        if (cur_len >= len) {
            break;
        }
        if (temp == _buffer_write) {
            if (_buffer_write->GetNext()) {
                _buffer_write = _buffer_write->GetNext();

            } else {
                _Reset();
            }
        }
        del_temp = temp;
        temp = temp->GetNext();
        _pool->PoolDelete<CLoopBuffer>(del_temp);
        _buff_count--;
    }
    _buffer_read = temp;
    return cur_len;
}

int CBuffer::Write(const char* str, int len) {
    std::unique_lock<std::mutex> lock(_mutex);
    CLoopBuffer* prv_temp = nullptr;
    CLoopBuffer* temp = _buffer_write;
    int cur_len = 0;
    while (1) {
        if (temp == nullptr) {
            temp = _pool->PoolNew<CLoopBuffer>(_pool);
            _buff_count++;
            // set buffer end to next node
            _buffer_end = temp;
        }
        if (prv_temp != nullptr) {
            prv_temp->SetNext(temp);
        }

        cur_len += temp->Write(str + cur_len, len - cur_len);

        // set buffer read to first
        if (_buffer_read == nullptr) {
            _buffer_read = temp;
        }

        prv_temp = temp;
        if (cur_len >= len) {
            break;
        }
        temp = temp->GetNext();
    }
    _buffer_write = temp;
    return cur_len;
}

void CBuffer::Clear(int len) {
    if (len == 0) {
        std::unique_lock<std::mutex> lock(_mutex);
        CLoopBuffer* temp = _buffer_read;
        CLoopBuffer* cur = nullptr;
        while (temp) {
            cur = temp;
            temp = temp->GetNext();
            _pool->PoolDelete<CLoopBuffer>(cur);
            _buff_count--;
        }
        _Reset();
        return;
    }
    
    std::unique_lock<std::mutex> lock(_mutex);
    CLoopBuffer* temp = _buffer_read;
    CLoopBuffer* del_temp = nullptr;
    int cur_len = 0;
    while (temp) {
        cur_len += temp->Clear(len - cur_len);
        if (cur_len >= len) {
            break;
        }
        if (temp == _buffer_write) {
            if (_buffer_write->GetNext()) {
                _buffer_write = _buffer_write->GetNext();

            } else {
                _Reset();
            }
        }
        del_temp = temp;
        temp = temp->GetNext();
        _pool->PoolDelete<CLoopBuffer>(del_temp);
        _buff_count--;
    }
    _buffer_read = temp;
}

int CBuffer::MoveWritePt(int len) {
    std::unique_lock<std::mutex> lock(_mutex);
    CLoopBuffer* temp = _buffer_write;
    int cur_len = 0;
    while (temp) {
        cur_len += temp->MoveWritePt(len - cur_len);
        if (temp == _buffer_end || len <= cur_len) {
            break;
        }
        temp = temp->GetNext();
    }
    _buffer_write = temp;
    return cur_len;
}

int CBuffer::ReadUntil(char* res, int len) {
    if (GetCanReadLength() < len) {
        return 0;

    } else {
        return Read(res, len);
    }
}

int CBuffer::ReadUntil(char* res, int len, const char* find, int find_len, int& need_len) {
    int size = FindStr(find, find_len);
    if (size) {
        if (size <= len) {
            return Read(res, size);

        } else {
            need_len = size;
            return 0;
        }
    }
    return 0;
}

int CBuffer::GetFreeLength() {
    if (!_buffer_write) {
        return 0;
    }
    
    std::unique_lock<std::mutex> lock(_mutex);
    CLoopBuffer* temp = _buffer_write;
    int cur_len = 0;
    while (temp) {
        cur_len += temp->GetFreeLength();
        if (temp == _buffer_end) {
            break;
        }
        temp = temp->GetNext();
    }
    return cur_len;
}

int CBuffer::GetCanReadLength() {
    if (!_buffer_read) {
        return 0;
    }

    std::unique_lock<std::mutex> lock(_mutex);
    CLoopBuffer* temp = _buffer_read;
    int cur_len = 0;
    while (temp) {
        cur_len += temp->GetCanReadLength();
        if (temp == _buffer_write) {
            break;
        }
        temp = temp->GetNext();
    }
    return cur_len;
}

int CBuffer::GetFreeMemoryBlock(std::vector<iovec>& block_vec, int size) {
    void* mem_1 = nullptr;
    void* mem_2 = nullptr;
    int mem_len_1 = 0;
    int mem_len_2 = 0;

    CLoopBuffer* temp = _buffer_write;
    CLoopBuffer* prv_temp = nullptr;
    int cur_len = 0;
    if (size > 0) {
        std::unique_lock<std::mutex> lock(_mutex);
        while (cur_len < size) {
            if (temp == nullptr) {
                temp = _pool->PoolNew<CLoopBuffer>(_pool);
                _buff_count++;
            }
            if (prv_temp != nullptr) {
                prv_temp->SetNext(temp);
            }
        
            temp->GetFreeMemoryBlock(mem_1, mem_len_1, mem_2, mem_len_2);
            if (mem_len_1 > 0) {
                block_vec.push_back(iovec(mem_1, mem_len_1));
                cur_len += mem_len_1;
            }
            if (mem_len_2 > 0) {
                block_vec.push_back(iovec(mem_2, mem_len_2));
                cur_len += mem_len_2;
            }
            // set buffer read to first
            if (_buffer_read == nullptr) {
                _buffer_read = temp;
            }
            // set buffer write to first
            if (_buffer_write == nullptr) {
                _buffer_write = temp;
            }
            prv_temp = temp;
            temp = temp->GetNext();
        }
        _buffer_end = prv_temp;

    } else {
        std::unique_lock<std::mutex> lock(_mutex);
        while (temp) {
            temp->GetFreeMemoryBlock(mem_1, mem_len_1, mem_2, mem_len_2);
            if (mem_len_1 > 0) {
                block_vec.push_back(iovec(mem_1, mem_len_1));
                cur_len += mem_len_1;
            }
            if (mem_len_2 > 0) {
                block_vec.push_back(iovec(mem_2, mem_len_2));
                cur_len += mem_len_2;
            }
            if (temp == _buffer_end) {
                break;
            }
            temp = temp->GetNext();
        }
    }
    return cur_len;
}

int CBuffer::GetUseMemoryBlock(std::vector<iovec>& block_vec, int max_size) {
    void* mem_1 = nullptr;
    void* mem_2 = nullptr;
    int mem_len_1 = 0;
    int mem_len_2 = 0;

    std::unique_lock<std::mutex> lock(_mutex);
    CLoopBuffer* temp = _buffer_read;
    int cur_len = 0;
    while (temp) {
        temp->GetUseMemoryBlock(mem_1, mem_len_1, mem_2, mem_len_2);
        if (mem_len_1 > 0) {
            block_vec.push_back(iovec(mem_1, mem_len_1));
            cur_len += mem_len_1;
        }
        if (mem_len_2 > 0) {
            block_vec.push_back(iovec(mem_2, mem_len_2));
            cur_len += mem_len_2;
        }
        if (temp == _buffer_write) {
            break;
        }
        if (cur_len >= max_size) {
            break;
        }
        temp = temp->GetNext();
    }
    return cur_len;
}

int CBuffer::FindStr(const char* s, int s_len) const {
    if (!_buffer_read) {
        return 0;
    }

    CLoopBuffer* temp = _buffer_read;
    int cur_len = 0;
    int can_read_bytes = 0;
    while (temp) {
        can_read_bytes = temp->FindStr(s, s_len);
        if (can_read_bytes > 0) {
            cur_len += can_read_bytes;
            break;
        }
        if (temp == _buffer_write) {
            break;
        }
        cur_len += temp->GetCanReadLength();
        temp = temp->GetNext();
    }
    return cur_len;
}

void CBuffer::_Reset() {
    _buffer_end = nullptr;
    _buffer_read = nullptr;
    _buffer_write = nullptr; 
}

std::ostream& base::operator<< (std::ostream &out, const CBuffer &obj) {
    if (!obj._buffer_read) {
        return out;
    }
    CLoopBuffer* temp = obj._buffer_read;
    while (temp) {
        out << *temp;
        if (temp == obj._buffer_write) {
            break;
        }
        temp = temp->GetNext();
    }
    return out;
}