#include "views/view_hashes.hpp"

#include "providers/provider.hpp"

#include "crypto.hpp"

#include <vector>

#include "utils.hpp"

namespace hex {

    ViewHashes::ViewHashes(prv::Provider* &dataProvider) : View(), m_dataProvider(dataProvider) {
        View::subscribeEvent(Events::DataChanged, [this](const void*){
            this->m_shouldInvalidate = true;
        });
    }

    ViewHashes::~ViewHashes() {
        View::unsubscribeEvent(Events::DataChanged);
    }


    static void formatBigHexInt(auto dataArray, char *buffer, size_t bufferSize) {
        for (int i = 0; i < dataArray.size(); i++)
            snprintf(buffer + 8 * i, bufferSize - 8 * i, "%08X", hex::changeEndianess(dataArray[i], std::endian::big));
    }

    void ViewHashes::createView() {
        if (!this->m_windowOpen)
            return;

        if (ImGui::Begin("Hashing", &this->m_windowOpen, ImGuiWindowFlags_NoCollapse)) {
            ImGui::BeginChild("##scrolling", ImVec2(0, 0), false, ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoNav);
            ImGui::NewLine();

            if (this->m_dataProvider != nullptr && this->m_dataProvider->isAvailable()) {

                if (ImGui::Combo("Hash Function", &this->m_currHashFunction, HashFunctionNames,sizeof(HashFunctionNames) / sizeof(const char *)))
                    this->m_shouldInvalidate = true;

                ImGui::NewLine();
                ImGui::Separator();
                ImGui::NewLine();

                ImGui::InputInt("Begin", &this->m_hashStart, 0, 0, ImGuiInputTextFlags_CharsHexadecimal);
                if (ImGui::IsItemEdited()) this->m_shouldInvalidate = true;

                ImGui::InputInt("End", &this->m_hashEnd, 0, 0, ImGuiInputTextFlags_CharsHexadecimal);
                if (ImGui::IsItemEdited()) this->m_shouldInvalidate = true;

                size_t dataSize = this->m_dataProvider->getSize();
                if (this->m_hashEnd >= dataSize)
                    this->m_hashEnd = dataSize - 1;

                ImGui::NewLine();
                ImGui::Separator();
                ImGui::NewLine();

                if (this->m_hashEnd >= this->m_hashStart) {

                    switch (this->m_currHashFunction) {
                        case 0: // CRC16
                        {
                            int polynomial = 0, init = 0;

                            ImGui::InputInt("Initial Value", &init, 0, 0, ImGuiInputTextFlags_CharsHexadecimal);
                            if (ImGui::IsItemEdited()) this->m_shouldInvalidate = true;

                            ImGui::InputInt("Polynomial", &polynomial, 0, 0, ImGuiInputTextFlags_CharsHexadecimal);
                            if (ImGui::IsItemEdited()) this->m_shouldInvalidate = true;

                            ImGui::NewLine();
                            ImGui::Separator();
                            ImGui::NewLine();

                            static u16 result = 0;

                            if (this->m_shouldInvalidate)
                                result = crc16(this->m_dataProvider, this->m_hashStart, this->m_hashEnd - this->m_hashStart + 1, polynomial, init);

                            char buffer[sizeof(result) * 2 + 1];
                            snprintf(buffer, sizeof(buffer), "%04X", result);
                            ImGui::InputText("Hash value", buffer, ImGuiInputTextFlags_ReadOnly);
                        }
                            break;
                        case 1: // CRC32
                        {
                            int polynomial = 0, init = 0;

                            ImGui::InputInt("Initial Value", &init, 0, 0, ImGuiInputTextFlags_CharsHexadecimal);
                            if (ImGui::IsItemEdited()) this->m_shouldInvalidate = true;

                            ImGui::InputInt("Polynomial", &polynomial, 0, 0, ImGuiInputTextFlags_CharsHexadecimal);
                            if (ImGui::IsItemEdited()) this->m_shouldInvalidate = true;

                            ImGui::NewLine();
                            ImGui::Separator();
                            ImGui::NewLine();

                            static u32 result = 0;

                            if (this->m_shouldInvalidate)
                                result = crc32(this->m_dataProvider, this->m_hashStart, this->m_hashEnd - this->m_hashStart + 1, polynomial, init);

                            char buffer[sizeof(result) * 2 + 1];
                            snprintf(buffer, sizeof(buffer), "%08X", result);
                            ImGui::InputText("Hash value", buffer, ImGuiInputTextFlags_ReadOnly);
                        }
                            break;
                        case 2: // MD4
                        {
                            static std::array<u32, 4> result;

                            if (this->m_shouldInvalidate)
                                result = md4(this->m_dataProvider, this->m_hashStart, this->m_hashEnd - this->m_hashStart + 1);

                            char buffer[sizeof(result) * 2 + 1];
                            formatBigHexInt(result, buffer, sizeof(buffer));
                            ImGui::InputText("Hash value", buffer, ImGuiInputTextFlags_ReadOnly);
                        }
                            break;
                        case 3: // MD5
                        {
                            static std::array<u32, 4> result = { 0 };

                            if (this->m_shouldInvalidate)
                                result = md5(this->m_dataProvider, this->m_hashStart, this->m_hashEnd - this->m_hashStart + 1);

                            char buffer[sizeof(result) * 2 + 1];
                            formatBigHexInt(result, buffer, sizeof(buffer));
                            ImGui::InputText("Hash value", buffer, ImGuiInputTextFlags_ReadOnly);
                        }
                            break;
                        case 4: // SHA-1
                        {
                            static std::array<u32, 5> result = { 0 };

                            if (this->m_shouldInvalidate)
                                result = sha1(this->m_dataProvider, this->m_hashStart, this->m_hashEnd - this->m_hashStart + 1);

                            char buffer[sizeof(result) * 2 + 1];
                            formatBigHexInt(result, buffer, sizeof(buffer));
                            ImGui::InputText("Hash value", buffer, ImGuiInputTextFlags_ReadOnly);
                        }
                            break;
                        case 5: // SHA-224
                        {
                            static std::array<u32, 7> result = { 0 };

                            if (this->m_shouldInvalidate)
                                result = sha224(this->m_dataProvider, this->m_hashStart, this->m_hashEnd - this->m_hashStart + 1);

                            char buffer[sizeof(result) * 2 + 1];
                            formatBigHexInt(result, buffer, sizeof(buffer));
                            ImGui::InputText("Hash value", buffer, ImGuiInputTextFlags_ReadOnly);
                        }
                            break;
                        case 6: // SHA-256
                        {
                            static std::array<u32, 8> result;

                            if (this->m_shouldInvalidate)
                                result = sha256(this->m_dataProvider, this->m_hashStart, this->m_hashEnd - this->m_hashStart + 1);

                            char buffer[sizeof(result) * 2 + 1];
                            formatBigHexInt(result, buffer, sizeof(buffer));
                            ImGui::InputText("Hash value", buffer, ImGuiInputTextFlags_ReadOnly);
                        }
                            break;
                        case 7: // SHA-384
                        {
                            static std::array<u32, 12> result;

                            if (this->m_shouldInvalidate)
                                result = sha384(this->m_dataProvider, this->m_hashStart, this->m_hashEnd - this->m_hashStart + 1);

                            char buffer[sizeof(result) * 2 + 1];
                            formatBigHexInt(result, buffer, sizeof(buffer));
                            ImGui::InputText("Hash value", buffer, ImGuiInputTextFlags_ReadOnly);
                        }
                            break;
                        case 8: // SHA-512
                        {
                            static std::array<u32, 16> result;

                            if (this->m_shouldInvalidate)
                                result = sha512(this->m_dataProvider, this->m_hashStart, this->m_hashEnd - this->m_hashStart + 1);

                            char buffer[sizeof(result) * 2 + 1];
                            formatBigHexInt(result, buffer, sizeof(buffer));
                            ImGui::InputText("Hash value", buffer, ImGuiInputTextFlags_ReadOnly);
                        }
                            break;
                    }

                }

                this->m_shouldInvalidate = false;
            }
            ImGui::EndChild();
        }
        ImGui::End();
    }

    void ViewHashes::createMenu() {
        if (ImGui::BeginMenu("View")) {
            ImGui::MenuItem("Hash View", "", &this->m_windowOpen);
            ImGui::EndMenu();
        }
    }

}