#include "Ires.hpp"

#include "AppConfig.hpp"
#include "EditorCore.hpp"
#include "EditorUtils.hpp"
#include "Material.hpp"
#include "Shader.hpp"
#include "Sprite.hpp"
#include "Texture.hpp"

#include <Macros.hpp>
#include <Metadata.hpp>
#include <RapidJsonHelper.hpp>
#include <ScopeGuard.hpp>
#include <Utils.hpp>

#include <imgui.h>
#include <misc/cpp/imgui_stdlib.h>
#include <rapidjson/document.h>
#include <rapidjson/filereadstream.h>
#include <rapidjson/filewritestream.h>
#include <rapidjson/prettywriter.h>
#include <rapidjson/writer.h>
#include <algorithm>
#include <cassert>

namespace fs = std::filesystem;
using namespace std::literals;

IresObject::IresObject(Kind kind)
	: mKind{ kind } {
}

std::unique_ptr<IresObject> IresObject::Create(Kind kind) {
	switch (kind) {
		case KD_Texture: return std::make_unique<IresTexture>();
		case KD_Shader: return std::make_unique<IresShader>();
		case KD_Material: return std::make_unique<IresMaterial>();
		case KD_SpriteFiles: return std::make_unique<IresSpriteFiles>();
		case KD_Spritesheet: return std::make_unique<IresSpritesheet>();
		case KD_COUNT: break;
	}
	return nullptr;
}

bool IresObject::IsAnnoymous() const {
	return mName.empty();
}

void IresObject::SetName(std::string name) {
	if (mMan) {
		mMan->Rename(this, std::move(name));
	} else {
		mName = std::move(name);
	}
}

void IresObject::ShowNameSafe(IresObject* ires) {
	if (ires) {
		ires->ShowName();
	} else {
		ShowNameNull();
	}
}

void IresObject::ShowNameNull() {
	ImGui::Text("<null>");
}

void IresObject::ShowName() const {
	if (IsAnnoymous()) {
		ImGui::Text("<annoymous %p>", (void*)this);
	} else {
		ImGui::Text("%s", mName.c_str());
	}
}

void IresObject::ShowReferenceSafe(IEditor& editor, IresObject* ires) {
	if (ires) {
		ires->ShowReference(editor);
	} else {
		ShowReferenceNull(editor);
	}
}

void IresObject::ShowReferenceNull(IEditor& editor) {
	ImGui::PushStyleColor(ImGuiCol_Text, ImGui::GetStyle().Colors[ImGuiCol_ButtonHovered]);
	ImGui::Text("<null>");
	ImGui::PopStyleColor();
	ImGui::AddUnderLine(ImGui::GetStyle().Colors[ImGuiCol_Button]);
}

void IresObject::ShowReference(IEditor& editor) {
	ImGui::PushStyleColor(ImGuiCol_Text, ImGui::GetStyle().Colors[ImGuiCol_ButtonHovered]);
	if (IsAnnoymous()) {
		ImGui::Text("<annoymous %p>", (void*)this);
	} else {
		ImGui::Text("%s", mName.c_str());
	}
	ImGui::PopStyleColor();
	if (ImGui::IsItemHovered()) {
		if (ImGui::IsMouseClicked(ImGuiMouseButton_Left)) {
			editor.GetInspector().SelectTarget(IEditorInspector::ITT_Ires, this);
		}
		ImGui::AddUnderLine(ImGui::GetStyle().Colors[ImGuiCol_ButtonHovered]);
	} else {
		ImGui::AddUnderLine(ImGui::GetStyle().Colors[ImGuiCol_Button]);
	}
}

void IresObject::ShowEditor(IEditor& editor) {
	ImGui::Text("%.*s", PRINTF_STRING_VIEW(Metadata::EnumToString(mKind)));

	bool isAnnoymous = mName.empty();
	if (isAnnoymous) {
		ImGui::Text("Name: <annoymous: %p>", (void*)this);
	} else {
		ImGui::Text("Name: %s", mName.c_str());
	}

	if (mUid.IsNull()) {
		ImGui::TextUnformatted("Uid: <none>");
	} else {
		ImGui::Text("Uid: %lx-%lx", mUid.upper, mUid.lower);
	}
}

void IresObject::WriteFull(IresWritingContext& ctx, IresObject* ires, rapidjson::Value& value, rapidjson::Document& root) {
	rapidjson::Value rvIres(rapidjson::kObjectType);
	ires->Write(ctx, rvIres, root);

	value.AddMember("Type", rapidjson::StringRef(Metadata::EnumToString(ires->GetKind())), root.GetAllocator());
	value.AddMember("Uid", ires->mUid.Write(root), root.GetAllocator());
	value.AddMember("Value", rvIres, root.GetAllocator());
}

std::unique_ptr<IresObject> IresObject::ReadFull(IresLoadingContext& ctx, const rapidjson::Value& value) {
	auto ires = ReadBasic(value);
	if (!ires) {
		return nullptr;
	}

	if (!ReadPartial(ctx, ires.get(), value)) {
		return nullptr;
	}

	return ires;
}

std::unique_ptr<IresObject> IresObject::ReadBasic(const rapidjson::Value& value) {
	auto rvType = rapidjson::GetProperty(value, rapidjson::kStringType, "Type"sv);
	if (!rvType) return nullptr;
	auto kind = Metadata::EnumFromString<Kind>(rapidjson::AsStringView(*rvType));
	assert(kind.has_value());
	auto ires = Create(kind.value());
	if (!ires) return nullptr;

	auto rvUid = rapidjson::GetProperty(value, rapidjson::kArrayType, "Uid"sv);
	if (!rvUid) return nullptr;
	ires->mUid.Read(*rvUid);

	return ires;
}

bool IresObject::ReadPartial(IresLoadingContext& ctx, IresObject* ires, const rapidjson::Value& value) {
	auto rvValue = rapidjson::GetProperty(value, "Value"sv);
	if (!rvValue) return false;
	ires->Read(ctx, *rvValue);
	return true;
}

void IresObject::Write(IresWritingContext& ctx, rapidjson::Value& value, rapidjson::Document& root) const {
}

void IresObject::Read(IresLoadingContext& ctx, const rapidjson::Value& value) {
}

void IresManager::DiscoverFilesDesignatedLocation() {
	auto path = AppConfig::assetDirPath / "Ires";
	DiscoverFiles(path);
}

void IresManager::DiscoverFiles(const fs::path& dir) {
	struct LoadCandidate {
		fs::path path;
		rapidjson::Document data;
		RcPtr<IresObject> ires;
	};

	class IresLoadTimeContext final : public IresLoadingContext {
	public:
		// NOTE: pointer stability required
		robin_hood::unordered_node_map<Uid, LoadCandidate> candidates;
		std::vector<std::vector<LoadCandidate*>> candidatesByKind;

		IresLoadTimeContext() {
			candidatesByKind.resize((int)IresObject::KD_COUNT);
		}

		std::vector<LoadCandidate*>& GetByKind(IresObject::Kind kind) {
			int i = static_cast<int>(kind);
			return candidatesByKind[i];
		}

		virtual IresObject* FindIres(const Uid& uid) const override {
			auto iter = candidates.find(uid);
			if (iter != candidates.end()) {
				auto& cand = iter->second;
				return cand.ires.Get();
			} else {
				return nullptr;
			}
		}
	} ctx;

	for (auto& item : fs::directory_iterator(dir)) {
		if (!item.is_regular_file()) {
			continue;
		}
		if (item.path().extension() != ".json") {
			continue;
		}

		auto file = Utils::OpenCstdioFile(item.path(), Utils::Read);
		if (!file) {
			fprintf(stderr, "Ires file [" PLATFORM_PATH_STR "] Failed to open file.", item.path().c_str());
			continue;
		}
		DEFER { fclose(file); };

		char readerBuffer[65536];
		rapidjson::FileReadStream stream(file, readerBuffer, sizeof(readerBuffer));

		rapidjson::Document root;
		root.ParseStream(stream);

		auto ires = IresObject::ReadBasic(root);
		if (!ires) {
			fprintf(stderr, "Ires file: [" PLATFORM_PATH_STR "] Failed to parse header.", item.path().c_str());
			continue;
		}

		// Load name from filename
		ires->mName = item.path().filename().replace_extension().string();
		auto& iresName = ires->mName;

		// Load uid should be handled by IresObject::ReadBasic
		assert(!ires->mUid.IsNull());
		auto iresUid = ires->GetUid();

		auto iresKind = ires->GetKind();

		auto&& [iter, DISCARD] = ctx.candidates.try_emplace(
			iresUid,
			LoadCandidate{
				.path = item.path(),
				.data = std::move(root),
				.ires = RcPtr(ires.release()),
			});
		auto& cand = iter->second;

		ctx.GetByKind(iresKind).push_back(&cand);
	}

	// Load Ires in order by type, there are dependencies between them
	// TODO full arbitary dependency between Ires
	for (int i = 0; i < (int)IresObject::KD_COUNT; ++i) {
		auto kind = static_cast<IresObject::Kind>(i);
		auto& list = ctx.GetByKind(kind);
		for (auto cand : list) {
			auto& ires = cand->ires;

			if (!IresObject::ReadPartial(ctx, ires.Get(), cand->data)) {
				fprintf(stderr, "Ires file: [" PLATFORM_PATH_STR "] Failed to parse object data.", cand->path.c_str());
				continue;
			}

			ires->mMan = this;
			mObjByUid.try_emplace(ires->GetUid(), ires);
		}
	}
}

std::pair<IresObject*, bool> IresManager::Add(IresObject* ires) {
	auto& name = ires->mName;
	if (name.empty()) {
		name = Utils::MakeRandomNumberedName(Metadata::EnumToString(ires->GetKind()).data());
	}

	auto& uid = ires->mUid;
	if (uid.IsNull()) {
		uid = Uid::Create();
	}

	auto [iter, inserted] = mObjByUid.try_emplace(uid, ires);
	if (inserted) {
		ires->mMan = this;
		// TODO handle full path
		return { ires, true };
	} else {
		return { iter->second.Get(), false };
	}
}

IresObject* IresManager::Load(const fs::path& filePath) {
	auto file = Utils::OpenCstdioFile(filePath, Utils::Read);
	if (!file) return nullptr;
	DEFER { fclose(file); };

	char readerBuffer[65536];
	rapidjson::FileReadStream stream(file, readerBuffer, sizeof(readerBuffer));

	rapidjson::Document root;
	root.ParseStream(stream);

	auto ires = IresObject::ReadFull(*this, root);
	if (!ires) {
		return nullptr;
	}

	// Load uid should be handled by IresObject::ReadFull
	assert(!ires->mUid.IsNull());
	// Load name from filename
	ires->mName = filePath.filename().replace_extension().string();
	Add(ires.get());

	return ires.release();
}

static fs::path GetDesignatedPath(IresObject* ires) {
	return AppConfig::assetDirPath / "Ires" / fs::path(ires->GetName()).replace_extension(".json");
}

void IresManager::Delete(IresObject* ires) {
	// TODO
}

bool IresManager::Rename(IresObject* ires, std::string newName) {
	auto oldPath = GetDesignatedPath(ires);
	ires->mName = std::move(newName);
	auto newPath = GetDesignatedPath(ires);
	if (fs::exists(oldPath)) {
		fs::rename(oldPath, newPath);
	}

	// TODO validate no name duplication
#if 0
	if (mObjByPath.contains(newName)) {
		return false;
	}

	// Keep the material from being deleted, in case the old entry in map is the only one existing
	RcPtr rc(ires);

	// Remove old entry (must do before replacing Material::mName, because the std::string_view in the map is a reference to it)
	mObjByPath.erase(ires->GetName());

	// Add new entry
	ires->mName = std::move(newName);
	// TODO handle full path
	mObjByPath.try_emplace(ires->GetName(), ires);
#endif
	return true;
}

void IresManager::Reload(IresObject* ires) {
	auto file = Utils::OpenCstdioFile(GetDesignatedPath(ires), Utils::Read);
	if (!file) return;
	DEFER { fclose(file); };

	char readerBuffer[65536];
	rapidjson::FileReadStream stream(file, readerBuffer, sizeof(readerBuffer));

	rapidjson::Document root;
	root.ParseStream(stream);

	IresObject::ReadPartial(*this, ires, root);
}

void IresManager::Save(IresObject* ires) {
	Save(ires, GetDesignatedPath(ires));
}

void IresManager::Save(IresObject* ires, const fs::path& filePath) {
	rapidjson::Document root(rapidjson::kObjectType);

	IresObject::WriteFull(*this, ires, root, root);

	auto file = Utils::OpenCstdioFile(filePath, Utils::WriteTruncate);
	if (!file) return;
	DEFER { fclose(file); };

	char writerBuffer[65536];
	rapidjson::FileWriteStream stream(file, writerBuffer, sizeof(writerBuffer));
	rapidjson::PrettyWriter<rapidjson::FileWriteStream> writer(stream);
	writer.SetFormatOptions(rapidjson::PrettyFormatOptions::kFormatSingleLineArray);
	root.Accept(writer);
}

IresObject* IresManager::FindIres(const Uid& uid) const {
	auto iter = mObjByUid.find(uid);
	if (iter != mObjByUid.end()) {
		return iter->second.Get();
	} else {
		return nullptr;
	}
}

#include <generated/Ires.gs.inl>