#include <pybind11/pybind11.h>
#include <pybind11/stl.h>  // 支持 std::vector, std::map 等
#include <nlohmann/json.hpp>
#include <cstring>
#include <cstdint>
#include <vector>
#include <string>
#include <fstream>
#include <array>
#include <algorithm>
#include <openssl/evp.h>
#include "native_logger.hpp"

namespace py = pybind11;
using json = nlohmann::json;

namespace {
    // 配置项
    const std::string _cfg_server_ip = "www.shelingxingqiu.com";
    const int _cfg_server_port = 50005;

    // OTA AEAD format: MAGIC(7) | nonce(12) | ciphertext(N) | tag(16)
    constexpr const char* kOtaMagic = "AROTAE1";
    constexpr size_t kOtaMagicLen = 7;
    constexpr size_t kGcmNonceLen = 12;
    constexpr size_t kGcmTagLen = 16;

    // 固定 32-byte AES-256-GCM key（提高被直接查看的成本；不是绝对安全）
    // 注意：需要与打包端传入的 --aead-key-hex 保持一致。
    static std::array<uint8_t, 32> ota_key_bytes() {
        // 简单拆分混淆：key = a XOR b
        static const std::array<uint8_t, 32> a = {
            0x92,0x99,0x4d,0x06,0x6f,0xb6,0xa6,0x3d,0x85,0x08,0xbe,0x73,0x5e,0x73,0x4d,0x8a,
            0x53,0x88,0xe6,0x99,0xfc,0x10,0x29,0xb9,0x16,0x9b,0xe7,0x0c,0x65,0x21,0x1c,0xce
        };
        static const std::array<uint8_t, 32> b = {
            0xcf,0x60,0xa2,0xc2,0x32,0x7a,0x61,0xb0,0x4c,0x8e,0x8a,0x62,0x31,0xc7,0x82,0xff,
            0xec,0xac,0xa1,0x04,0x2a,0x4d,0xaa,0xf2,0xb0,0x5b,0x39,0x2b,0xf4,0xb3,0xad,0xad
        };
        std::array<uint8_t, 32> k{};
        for (size_t i = 0; i < k.size(); i++) k[i] = static_cast<uint8_t>(a[i] ^ b[i]);
        return k;
    }
}

// 定义获取配置的函数
py::dict get_config() {
    py::dict config;
    config["SERVER_IP"] = _cfg_server_ip;
    config["SERVER_PORT"] = _cfg_server_port;
    return config;
}


// 辅助函数：将 py::dict 转为 nlohmann::json
json py_dict_to_json(py::dict d) {
    json j;
    for (auto item : d) {
        std::string key = py::str(item.first);
        py::object val = py::reinterpret_borrow<py::object>(item.second);
        
        if (py::isinstance<py::dict>(val)) {
            j[key] = py_dict_to_json(py::cast<py::dict>(val));
        } else if (py::isinstance<py::list>(val)) {
            py::list py_list = py::cast<py::list>(val);
            json arr = json::array();
            for (auto elem : py_list) {
                py::object elem_obj = py::reinterpret_borrow<py::object>(elem);
                if (py::isinstance<py::dict>(elem_obj)) {
                    arr.push_back(py_dict_to_json(py::cast<py::dict>(elem_obj)));
                } else if (py::isinstance<py::int_>(elem_obj)) {
                    arr.push_back(py::cast<int64_t>(elem_obj));
                } else if (py::isinstance<py::float_>(elem_obj)) {
                    arr.push_back(py::cast<double>(elem_obj));
                } else {
                    arr.push_back(py::str(elem_obj));
                }
            }
            j[key] = arr;
        } else if (py::isinstance<py::int_>(val)) {
            j[key] = py::cast<int64_t>(val);
        } else if (py::isinstance<py::float_>(val)) {
            j[key] = py::cast<double>(val);
        } else if (py::isinstance<py::bool_>(val)) {
            j[key] = py::cast<bool>(val);
        } else if (val.is_none()) {
            j[key] = nullptr;
        } else {
            j[key] = py::str(val);
        }
    }
    return j;
}

// 辅助函数：将 nlohmann::json 转为 py::dict
py::dict json_to_py_dict(const json& j) {
    py::dict d;
    if (j.is_object()) {
        for (auto& item : j.items()) {
            std::string key = item.key();
            json val = item.value();
            
            if (val.is_object()) {
                d[py::str(key)] = json_to_py_dict(val);
            } else if (val.is_array()) {
                py::list py_list;
                for (auto& elem : val) {
                    if (elem.is_object()) {
                        py_list.append(json_to_py_dict(elem));
                    } else if (elem.is_number_integer()) {
                        py_list.append(py::int_(elem.get<int64_t>()));
                    } else if (elem.is_number_float()) {
                        py_list.append(py::float_(elem.get<double>()));
                    } else if (elem.is_boolean()) {
                        py_list.append(py::bool_(elem.get<bool>()));
                    } else if (elem.is_null()) {
                        py_list.append(py::none());
                    } else {
                        py_list.append(py::str(elem.get<std::string>()));
                    }
                }
                d[py::str(key)] = py_list;
            } else if (val.is_number_integer()) {
                d[py::str(key)] = py::int_(val.get<int64_t>());
            } else if (val.is_number_float()) {
                d[py::str(key)] = py::float_(val.get<double>());
            } else if (val.is_boolean()) {
                d[py::str(key)] = py::bool_(val.get<bool>());
            } else if (val.is_null()) {
                d[py::str(key)] = py::none();
            } else {
                d[py::str(key)] = py::str(val.get<std::string>());
            }
        }
    }
    return d;
}

static bool read_file_all(const std::string& path, std::vector<uint8_t>& out) {
    std::ifstream ifs(path, std::ios::binary);
    if (!ifs) return false;
    ifs.seekg(0, std::ios::end);
    std::streampos size = ifs.tellg();
    if (size <= 0) return false;
    ifs.seekg(0, std::ios::beg);
    out.resize(static_cast<size_t>(size));
    if (!ifs.read(reinterpret_cast<char*>(out.data()), size)) return false;
    return true;
}

static bool write_file_all(const std::string& path, const uint8_t* data, size_t len) {
    std::ofstream ofs(path, std::ios::binary | std::ios::trunc);
    if (!ofs) return false;
    ofs.write(reinterpret_cast<const char*>(data), static_cast<std::streamsize>(len));
    return static_cast<bool>(ofs);
}

static bool decrypt_ota_file_impl(const std::string& input_path, const std::string& output_zip_path) {
    std::vector<uint8_t> in;
    if (!read_file_all(input_path, in)) {
        netcore::log_error(std::string("decrypt_ota_file: read failed: ") + input_path);
        return false;
    }

    const size_t min_len = kOtaMagicLen + kGcmNonceLen + kGcmTagLen + 1;
    if (in.size() < min_len) {
        netcore::log_error("decrypt_ota_file: too short");
        return false;
    }
    if (!std::equal(in.begin(), in.begin() + kOtaMagicLen, reinterpret_cast<const uint8_t*>(kOtaMagic))) {
        netcore::log_error("decrypt_ota_file: bad magic");
        return false;
    }

    const uint8_t* nonce = in.data() + kOtaMagicLen;
    const uint8_t* ct_and_tag = in.data() + kOtaMagicLen + kGcmNonceLen;
    const size_t ct_and_tag_len = in.size() - (kOtaMagicLen + kGcmNonceLen);
    if (ct_and_tag_len <= kGcmTagLen) {
        netcore::log_error("decrypt_ota_file: no ciphertext");
        return false;
    }
    const size_t ciphertext_len = ct_and_tag_len - kGcmTagLen;
    const uint8_t* ciphertext = ct_and_tag;
    const uint8_t* tag = ct_and_tag + ciphertext_len;

    std::vector<uint8_t> plain(ciphertext_len);
    int out_len1 = 0;
    int out_len2 = 0;

    EVP_CIPHER_CTX* ctx = EVP_CIPHER_CTX_new();
    if (!ctx) {
        netcore::log_error("decrypt_ota_file: EVP_CIPHER_CTX_new failed");
        return false;
    }

    bool ok = false;
    auto key = ota_key_bytes();

    do {
        if (1 != EVP_DecryptInit_ex(ctx, EVP_aes_256_gcm(), nullptr, nullptr, nullptr)) {
            netcore::log_error("decrypt_ota_file: DecryptInit failed");
            break;
        }
        if (1 != EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, static_cast<int>(kGcmNonceLen), nullptr)) {
            netcore::log_error("decrypt_ota_file: set ivlen failed");
            break;
        }
        if (1 != EVP_DecryptInit_ex(ctx, nullptr, nullptr, key.data(), nonce)) {
            netcore::log_error("decrypt_ota_file: set key/iv failed");
            break;
        }
        if (1 != EVP_DecryptUpdate(ctx, plain.data(), &out_len1, ciphertext, static_cast<int>(ciphertext_len))) {
            netcore::log_error("decrypt_ota_file: update failed");
            break;
        }
        if (1 != EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_TAG, static_cast<int>(kGcmTagLen), const_cast<uint8_t*>(tag))) {
            netcore::log_error("decrypt_ota_file: set tag failed");
            break;
        }
        if (1 != EVP_DecryptFinal_ex(ctx, plain.data() + out_len1, &out_len2)) {
            netcore::log_error("decrypt_ota_file: final failed (auth tag mismatch?)");
            break;
        }
        const size_t plain_len = static_cast<size_t>(out_len1 + out_len2);
        if (!write_file_all(output_zip_path, plain.data(), plain_len)) {
            netcore::log_error(std::string("decrypt_ota_file: write failed: ") + output_zip_path);
            break;
        }
        ok = true;
    } while (false);

    EVP_CIPHER_CTX_free(ctx);
    return ok;
}

// 打包 TCP 数据包
py::bytes make_packet(int msg_type, py::dict body_dict) {
    netcore::log_debug(std::string("make_packet msg_type=") + std::to_string(msg_type));
    // 1) 将 py::dict 转为 JSON 字符串
    json j = py_dict_to_json(body_dict);
    std::string body_str = j.dump();
    
    // 2) 计算 body_len 和 checksum
    uint32_t body_len = body_str.size();
    uint32_t checksum = body_len + msg_type;
    
    // 3) 打包头部（大端序）
    std::vector<uint8_t> packet;
    packet.reserve(12 + body_len);
    
    // body_len (big-endian, 4 bytes)
    packet.push_back((body_len >> 24) & 0xFF);
    packet.push_back((body_len >> 16) & 0xFF);
    packet.push_back((body_len >> 8) & 0xFF);
    packet.push_back(body_len & 0xFF);
    
    // msg_type (big-endian, 4 bytes)
    packet.push_back((msg_type >> 24) & 0xFF);
    packet.push_back((msg_type >> 16) & 0xFF);
    packet.push_back((msg_type >> 8) & 0xFF);
    packet.push_back(msg_type & 0xFF);
    
    // checksum (big-endian, 4 bytes)
    packet.push_back((checksum >> 24) & 0xFF);
    packet.push_back((checksum >> 16) & 0xFF);
    packet.push_back((checksum >> 8) & 0xFF);
    packet.push_back(checksum & 0xFF);
    
    // 4) 追加 body
    packet.insert(packet.end(), body_str.begin(), body_str.end());
    
    netcore::log_debug(std::string("make_packet done bytes=") + std::to_string(packet.size()));
    return py::bytes(reinterpret_cast<const char*>(packet.data()), packet.size());
}

// 解析 TCP 数据包
py::tuple parse_packet(py::bytes data) {
    // 1) 转换为 bytes view
    py::buffer_info buf = py::buffer(data).request();
    if (buf.size < 12) {
        netcore::log_error(std::string("parse_packet too_short len=") + std::to_string(buf.size));
        return py::make_tuple(py::none(), py::none());
    }
    
    const uint8_t* ptr = static_cast<const uint8_t*>(buf.ptr);
    
    // 2) 解析头部（大端序）
    uint32_t body_len = (ptr[0] << 24) | (ptr[1] << 16) | (ptr[2] << 8) | ptr[3];
    uint32_t msg_type = (ptr[4] << 24) | (ptr[5] << 16) | (ptr[6] << 8) | ptr[7];
    uint32_t checksum = (ptr[8] << 24) | (ptr[9] << 16) | (ptr[10] << 8) | ptr[11];
    
    // 3) 校验 checksum（可选，你现有代码不强制校验）
    // if (checksum != (body_len + msg_type)) {
    //     return py::make_tuple(py::none(), py::none());
    // }
    
    // 4) 检查长度
    uint32_t expected_len = 12 + body_len;
    if (buf.size < expected_len) {
        // 半包
        netcore::log_warn(std::string("parse_packet incomplete got=") + std::to_string(buf.size) +
                          " expected=" + std::to_string(expected_len));
        return py::make_tuple(py::none(), py::none());
    }
    
    // 5) 防御性检查：如果 data 比预期长，说明可能有粘包
    // （只解析第一个包，忽略多余数据）
    if (buf.size > expected_len) {
        netcore::log_warn(std::string("parse_packet concat got=") + std::to_string(buf.size) +
                          " expected=" + std::to_string(expected_len) +
                          " body_len=" + std::to_string(body_len) +
                          " msg_type=" + std::to_string(msg_type));
    }
    
    // 6) 提取 body 并解析 JSON
    std::string body_str(reinterpret_cast<const char*>(ptr + 12), body_len);
    
    try {
        json j = json::parse(body_str);
        py::dict body_dict = json_to_py_dict(j);
        return py::make_tuple(py::int_(msg_type), body_dict);
    } catch (const json::parse_error& e) {
        // JSON 解析失败，返回 raw（兼容你现有的逻辑）
        netcore::log_error(std::string("parse_packet json_parse_error: ") + e.what());
        py::dict raw_dict;
        raw_dict["raw"] = body_str;
        return py::make_tuple(py::int_(msg_type), raw_dict);
    } catch (const std::exception& e) {
        netcore::log_error(std::string("parse_packet json_parse_error: ") + e.what());
        py::dict raw_dict;
        raw_dict["raw"] = body_str;
        return py::make_tuple(py::int_(msg_type), raw_dict);
    }
}

PYBIND11_MODULE(archery_netcore, m) {
    m.doc() = "Archery net core (native, pybind11).";

    // Optional: configure native logger from Python.
    // Default log file: /maixapp/apps/t11/netcore.log
    m.def("set_log_file", [](const std::string& path) { netcore::set_log_file(path); }, py::arg("path"));
    m.def("set_log_level", [](int level) {
        if (level < 0) level = 0;
        if (level > 3) level = 3;
        netcore::set_log_level(static_cast<netcore::LogLevel>(level));
    }, py::arg("level"));
    m.def("log_test", [](const std::string& msg) {
        netcore::log_info(std::string("log_test: ") + msg);
    }, py::arg("msg"));

    m.def("make_packet", &make_packet,
          "Pack TCP packet: header (len+type+checksum) + JSON body",
          py::arg("msg_type"), py::arg("body_dict"));
    
    m.def("parse_packet", &parse_packet,
          "Parse TCP packet, return (msg_type, body_dict)");

    m.def("get_config", &get_config, "Get system configuration");

    m.def(
        "decrypt_ota_file",
        [](const std::string& input_path, const std::string& output_zip_path) {
            netcore::log_info(std::string("decrypt_ota_file in=") + input_path + " out=" + output_zip_path);
            return decrypt_ota_file_impl(input_path, output_zip_path);
        },
        py::arg("input_path"),
        py::arg("output_zip_path"),
        "Decrypt OTA encrypted file (MAGIC|nonce|ciphertext|tag) to plaintext zip."
    );

    // Minimal demo: return actions for inner_cmd=41 (manual trigger + ack)
    m.def("actions_for_inner_cmd", [](int inner_cmd) {
        py::list actions;

        if (inner_cmd == 41) {
            // 1) set manual trigger flag
            {
                py::dict a;
                a["type"] = "SET_FLAG";
                py::dict args;
                args["name"] = "manual_trigger_flag";
                args["value"] = true;
                a["args"] = args;
                actions.append(a);
            }

            // 2) enqueue trigger_ack
            {
                py::dict a;
                a["type"] = "ENQUEUE";
                py::dict args;
                args["msg_type"] = 2;
                args["high"] = false;
                py::dict body;
                body["result"] = "trigger_ack";
                args["body"] = body;
                a["args"] = args;
                actions.append(a);
            }
        }

        return actions;
    });
}