// 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;
namespace bp = boost::python;

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

Message::Blob::Blob(bp::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 = bp::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";
        }

    }
    bp::object codecs = bp::import("codecs");
    bp::object _decode = codecs.attr("decode");
    return bp::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();
}

bp::tuple Message::attachments() {
    bp::list l;

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

    return bp::tuple(l);
}

void Message::attachments(bp::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 = bp::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 = bp::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() {
    bp::list extra;
    return encrypt_message(*this, extra, ::PEP_enc_PGP_MIME, 0);
}

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

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

static bp::list update(bp::list il) {
    for (int i = 0; i < len(il); i++) {
        update(bp::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