#include "Ires.hpp"

#include "AppConfig.hpp"
#include "EditorUtils.hpp"
#include "RapidJsonHelper.hpp"
#include "ScopeGuard.hpp"
#include "Sprite.hpp"
#include "Texture.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/writer.h>
#include <algorithm>

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

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

std::string_view IresObject::ToString(Kind kind) {
	switch (kind) {
		case KD_Texture: return BRUSSEL_TAG_PREFIX_Ires "Texture"sv;
		case KD_SpriteFiles: return BRUSSEL_TAG_PREFIX_Ires "SpriteFiles"sv;
		case KD_Spritesheet: return BRUSSEL_TAG_PREFIX_Ires "Spritesheet"sv;
		case KD_COUNT: break;
	}
	return std::string_view();
}

IresObject::Kind IresObject::FromString(std::string_view name) {
	if (name == BRUSSEL_TAG_PREFIX_Ires "Texture"sv) return KD_Texture;
	if (name == BRUSSEL_TAG_PREFIX_Ires "SpriteFiles"sv) return KD_SpriteFiles;
	if (name == BRUSSEL_TAG_PREFIX_Ires "Spritesheet"sv) return KD_Spritesheet;
	return KD_COUNT;
}

std::unique_ptr<IresObject> IresObject::Create(Kind kind) {
	switch (kind) {
		case KD_Texture: return std::make_unique<IresTexture>();
		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::ShowEditor(EditorInstance& editor) {
	bool isAnnoymous = mName.empty();
	if (isAnnoymous) {
		ImGui::Text("<Annoymous Ires at %p>", (void*)this);
	} else {
		ImGui::Text("%s", mName.c_str());
	}
}

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

	value.AddMember("Type", rapidjson::StringRef(ToString(ires->GetKind())), root.GetAllocator());
	value.AddMember("Value", rvIres, root.GetAllocator());
}

std::unique_ptr<IresObject> IresObject::ReadFull(const rapidjson::Value& value) {
	auto rvType = rapidjson::GetProperty(value, rapidjson::kStringType, "Type"sv);
	if (!rvType) return nullptr;
	auto kind = FromString(rapidjson::AsStringView(*rvType));
	auto ires = Create(kind);
	if (!ires) return nullptr;

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

	return ires;
}

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

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

void IresManager::DiscoverFiles(const fs::path& dir) {
	// NOTE: by default does not follow symlinks
	// for (auto& item : fs::recursive_directory_iterator(dir)) {
	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) continue;
		DEFER { fclose(file); };

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

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

		auto ires = IresObject::ReadFull(root);
		if (!ires) {
			continue;
		}

		auto iden = fs::path(item.path()).replace_extension().lexically_relative(dir).string();
		std::replace(iden.begin(), iden.end(), '\\', '/');

#if 0
		std::string_view idenView(iden);

		// Trim heading slashes
		while (idenView.front() == '/') {
			idenView = std::string_view(idenView.data() + 1, idenView.size());
		}
		// Trim trailing slashes
		while (idenView.back() == '/') {
			idenView = std::string_view(idenView.data(), idenView.size() - 1);
		}
#endif
		ires->mName = std::move(iden);
		std::string_view key(ires->mName);
		mObjects.try_emplace(key, ires.release());
	}
}

std::pair<IresObject*, bool> IresManager::Add(IresObject* ires) {
	auto& name = ires->mName;
	if (name.empty()) {
		int n = std::rand();
		// NOTE: does not include null-terminator
		int size = snprintf(nullptr, 0, "Unnamed %s #%d", IresObject::ToString(ires->GetKind()).data(), n);
		name.resize(size); // std::string::resize handles storage for null-terminator alreaedy
		snprintf(name.data(), size, "Unnamed %s #%d", IresObject::ToString(ires->GetKind()).data(), n);
	}

	auto [iter, inserted] = mObjects.try_emplace(name, ires);
	if (inserted) {
		ires->mMan = this;
		return { ires, true };
	} else {
		return { iter->second.Get(), false };
	}
}

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

bool IresManager::Rename(IresObject* ires, std::string newName) {
	if (mObjects.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)
	mObjects.erase(ires->GetName());

	// Add new entry
	ires->mName = std::move(newName);
	mObjects.try_emplace(ires->GetName(), ires);

	return true;
}

IresObject* IresManager::Load(const fs::path& path) {
	// TODO
	return nullptr;
}

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

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(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(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::Writer<rapidjson::FileWriteStream> writer(stream);
	root.Accept(writer);
}

IresObject* IresManager::FindIres(std::string_view path) {
	auto iter = mObjects.find(path);
	if (iter != mObjects.end()) {
		return iter->second.Get();
	} else {
		return nullptr;
	}
}