// This file is under GNU Affero General Public License 3.0
// see LICENSE.txt

// System
#include <cstdlib>
#include <cstring>
#include <stdexcept>
#include <sstream>
#include <vector>
#include <Python.h>

// Engine
#include <pEp/mime.h>
#include <pEp/keymanagement.h>
#include <pEp/message_api.h>

// local
#include "message.hh"
#include "message_api.hh"

namespace pEp {
namespace PythonAdapter {
using namespace std;
using namespace boost::python;

Message::Blob::Blob(bloblist_t *bl, bool chained) :
    _bl(bl), part_of_chain(chained)
{
    if (!_bl)
        throw bad_alloc();
}

Message::Blob::Blob(object data, string mime_type, string filename) :
    _bl(new_bloblist(NULL, 0, NULL, NULL)), part_of_chain(false)
{
    if (!_bl)
        throw bad_alloc();

    Py_buffer src;
    int result = PyObject_GetBuffer(data.ptr(), &src, PyBUF_CONTIG_RO);
    if (result)
        throw invalid_argument("need a contiguous buffer to read");

    char *mem = (char *)malloc(src.len);
    if (!mem) {
        PyBuffer_Release(&src);
        throw bad_alloc();
    }

    memcpy(mem, src.buf, src.len);
    free(_bl->value);
    _bl->size = src.len;
    _bl->value = mem;

    PyBuffer_Release(&src);

    this->mime_type(mime_type);
    this->filename(filename);
}

Message::Blob::Blob(const Message::Blob& second) :
    _bl(second._bl), part_of_chain(true)
{

}

Message::Blob::~Blob()
{
    if (!part_of_chain) {
        free(_bl->value);
        free(_bl);
    }
}

string Message::Blob::_repr()
{
    stringstream build;
    build << "Blob(";
    if (!_bl) {
        build << "b'', '', ''";
    }
    else {
        build << "bytes(" << _bl->size << "), ";
        string mime_type;
        if (_bl->mime_type)
            mime_type = string(_bl->mime_type);
        string filename;
        if (_bl->filename)
            filename = string(_bl->filename);
        build << repr(mime_type) << ", ";
        build << repr(filename);
    }
    build << ")";
    return build.str();
}

int Message::Blob::getbuffer(PyObject *self, Py_buffer *view, int flags) {
    bloblist_t *bl = NULL;

    try {
        Message::Blob& blob = extract< Message::Blob& >(self);
        bl = blob._bl;
    }
    catch (exception& e) {
        PyErr_SetString(PyExc_RuntimeError, "extract not possible");
        view->obj = NULL;
        return -1;
    }

    if (!(bl && bl->value)) {
        PyErr_SetString(PyExc_RuntimeError, "no data available");
        view->obj = NULL;
        return -1;
    }

    return PyBuffer_FillInfo(view, self, bl->value, bl->size, 0, flags);
}

string Message::Blob::decode(string encoding)
{
    if (encoding == "") {
        string _mime_type = _bl->mime_type ? _bl->mime_type : "";
        encoding = "ascii";

        if (_mime_type == "application/pEp.sync")
            encoding = "pep.sync";

        if (_mime_type == "application/pEp.keyreset")
            encoding = "pep.distribution";

    }
    object codecs = import("codecs");
    object _decode = codecs.attr("decode");
    return call< string >(_decode.ptr(), this, encoding);
}

PyBufferProcs Message::Blob::bp = { getbuffer, NULL };

Message::Message(int dir, Identity *from)
    : _msg(new_message((PEP_msg_direction) dir), &free_message)
{
    if (!_msg)
        throw bad_alloc();

    if (from) {
        _msg->from = ::identity_dup(*from);
        if (!_msg->from)
            throw bad_alloc();
        _msg->dir = (PEP_msg_direction) dir;
    }
}

Message::Message(string mimetext)
    : _msg(NULL, &free_message)
{
    message *_cpy;
    PEP_STATUS status = mime_decode_message(mimetext.c_str(),
            mimetext.size(), &_cpy, NULL);
    switch (status) {
        case PEP_STATUS_OK:
            if (_cpy)
                _cpy->dir = PEP_dir_outgoing;
            else
                _cpy = new_message(PEP_dir_outgoing);

            if (!_cpy)
                throw bad_alloc();

            _msg = shared_ptr< message >(_cpy);
            break;

        case PEP_BUFFER_TOO_SMALL:
            throw runtime_error("mime_decode_message: buffer too small");

        case PEP_CANNOT_CREATE_TEMP_FILE:
            throw runtime_error("mime_decode_message: cannot create temp file");

        case PEP_OUT_OF_MEMORY:
            throw bad_alloc();

        default:
            stringstream build;
            build << "mime_decode_message: unknown error (" << (int) status << ")";
            throw runtime_error(build.str());
    }
}

Message::Message(const Message& second)
    : _msg(second._msg)
{
    if (!_msg.get())
        throw bad_alloc();
}

Message::Message(message *msg)
    : _msg(::message_dup(msg), &free_message)
{

}

Message::~Message()
{

}

Message::operator message *()
{
    return _msg.get();
}

Message::operator const message *() const
{
    return _msg.get();
}

string Message::_str()
{
    if (!(_msg->from && _msg->from->address && _msg->from->address[0]))
        throw out_of_range(".from_.address missing");

    char *mimetext;
    string result;

    PEP_STATUS status = mime_encode_message(*this, false, &mimetext, false);
    switch (status) {
        case PEP_STATUS_OK:
            result = mimetext;
            free(mimetext);
            break;

        case PEP_BUFFER_TOO_SMALL:
            throw runtime_error("mime_encode_message: buffer too small");

        case PEP_CANNOT_CREATE_TEMP_FILE:
            throw runtime_error("mime_encode_message: cannot create temp file");

        case PEP_OUT_OF_MEMORY:
            throw bad_alloc();

        default:
            stringstream build;
            build << "mime_encode_message: unknown error (" << (int) status << ")";
            throw runtime_error(build.str());
    }

    return result;
}

string Message::_repr()
{
    stringstream build;
    build << "Message(" << repr(_str()) << ")";
    return build.str();
}

boost::python::tuple Message::attachments()
{
    boost::python::list l;

    for (bloblist_t *bl = _msg->attachments; bl && bl->value; bl =
            bl->next) {
        l.append(Blob(bl, true));
    }

    return boost::python::tuple(l);
}

void Message::attachments(boost::python::list value)
{
    bloblist_t *bl = new_bloblist(NULL, 0, NULL, NULL);
    if (!bl)
        throw bad_alloc();

    bloblist_t *_l = bl;
    for (int i=0; i<len(value); i++) {
        Message::Blob& blob = extract< Message::Blob& >(value[i]);
        _l = bloblist_add(_l, blob._bl->value, blob._bl->size,
                blob._bl->mime_type, blob._bl->filename);
        if (!_l) {
            for (_l = bl; _l && _l->value; ) {
                free(_l->mime_type);
                free(_l->filename);
                bloblist_t *_ll = _l;
                _l = _l->next;
                free(_ll);
            }
            throw bad_alloc();
        }
    }

    for (int i=0; i<len(value); i++) {
        Message::Blob& blob = extract< Message::Blob& >(value[i]);
        blob._bl->value = NULL;
        blob._bl->size = 0;
        free(blob._bl->mime_type);
        blob._bl->mime_type = NULL;
        free(blob._bl->filename);
        blob._bl->filename = NULL;
    }

    free_bloblist(_msg->attachments);
    _msg->attachments = bl;
}

Message Message::encrypt()
{
    boost::python::list extra;
    return encrypt_message(*this, extra, PEP_enc_PGP_MIME, 0);
}

Message Message::_encrypt(boost::python::list extra, int enc_format, int flags)
{
    if (!enc_format)
        enc_format = PEP_enc_PGP_MIME;
    return encrypt_message(*this, extra, enc_format, flags);
}

boost::python::tuple Message::decrypt(int flags) {
    return pEp::PythonAdapter::decrypt_message(*this, flags);
}

PEP_rating Message::outgoing_rating()
{
    if (_msg->dir != PEP_dir_outgoing)
        throw invalid_argument("Message.dir must be outgoing");

    if (from().address() == "")
        throw invalid_argument("from.address needed");
    if (from().username() == "")
        throw invalid_argument("from.username needed");

    if (len(to()) + len(cc()) == 0)
        throw invalid_argument("either to or cc needed");

    PEP_STATUS status = myself(Adapter::session(), _msg->from);
    _throw_status(status);

    PEP_rating rating = PEP_rating_undefined;
    status = outgoing_message_rating(Adapter::session(), *this, &rating);
    _throw_status(status);

    return rating;
}

PEP_color Message::outgoing_color()
{
    return _color(outgoing_rating());
}

Message Message::copy()
{
    message *dup = message_dup(*this);
    if (!dup)
        throw bad_alloc();
    return Message(dup);
}

Message Message::deepcopy(dict&)
{
    return copy();
}

Message outgoing_message(Identity me)
{
    if (me.address().empty() || me.user_id().empty())
        throw runtime_error("at least address and user_id of own user needed");

    ::myself(Adapter::session(), me);
    auto m = Message(PEP_dir_outgoing, &me);
    return m;
}

static object update(Identity ident)
{
    if (ident.address().empty())
        throw runtime_error("at least address needed");
    update_identity(Adapter::session(), ident);
    return object(ident);
}

static boost::python::list update(boost::python::list il)
{
    for (int i=0; i<len(il); i++) {
        update(extract< Identity >(il[i]));
    }

    return il;
}

Message incoming_message(string mime_text)
{
    auto m = Message(mime_text);
    m.dir(PEP_dir_incoming);

    try {
        m.from(update(m.from()));
    }
    catch (out_of_range&) { }

    try {
        m.recv_by(update(m.recv_by()));
    }
    catch (out_of_range&) { }

    m.to(update(m.to()));
    m.cc(update(m.cc()));
    m.reply_to(update(m.reply_to()));

    return m;
}

} // namespace PythonAdapter
} // namespace pEp {