#include "UI.hpp"

#include <Cplt/Model/GlobalStates.hpp>
#include <Cplt/Model/Project.hpp>
#include <Cplt/Utils/I18n.hpp>

#include <IconsFontAwesome.h>
#include <imgui.h>
#include <imgui_stdlib.h>

namespace CPLT_UNITY_ID {

enum class ActionResult {
	Confirmed,
	Canceled,
	Pending,
};

/// \param list Item list that the item is in.
/// \param item A non-null pointer to the currently being edited item. It should not change until this function returns a non-\c ActionResult::Pending value.
template <class T>
ActionResult ItemEditor(ItemList<T>& list, T* item) {
	constexpr bool kHasDescription = requires(T t) {
		t.GetDescription();
	};
	constexpr bool kHasEmail = requires(T t) {
		t.GetEmail();
	};

	static bool duplicateName = false;

	static std::string name;
	static std::string description;
	static std::string email;
	if (name.empty()) {
		name = item->GetName();
		if constexpr (kHasDescription) description = item->GetDescription();
		if constexpr (kHasEmail) email = item->GetEmail();
	}

	auto ClearStates = [&]() {
		duplicateName = false;
		name = {};
		description = {};
	};

	if (ImGui::InputText(I18N_TEXT("Name", L10N_ITEM_COLUMN_NAME), &name)) {
		duplicateName = name != item->GetName() && list.Find(name) != nullptr;
	}
	if constexpr (kHasDescription) ImGui::InputText(I18N_TEXT("Description", L10N_ITEM_COLUMN_DESCRIPTION), &description);
	if constexpr (kHasEmail) ImGui::InputText(I18N_TEXT("Email", L10N_ITEM_COLUMN_EMAIL), &email);

	if (name.empty()) {
		ImGui::ErrorMessage(I18N_TEXT("Name cannot be empty", L10N_EMPTY_NAME_ERROR));
	}
	if (duplicateName) {
		ImGui::ErrorMessage(I18N_TEXT("Duplicate name", L10N_DUPLICATE_NAME_ERROR));
	}

	// Return Value
	auto rv = ActionResult::Pending;

	if (ImGui::Button(I18N_TEXT("Confirm", L10N_CONFIRM), name.empty() || duplicateName)) {
		if (item->GetName() != name) {
			item->SetName(std::move(name));
		}
		if constexpr (kHasDescription)
			if (item->GetDescription() != description) {
				item->SetDescription(std::move(description));
			}
		if constexpr (kHasEmail)
			if (item->GetEmail() != email) {
				item->SetEmail(std::move(email));
			}

		ImGui::CloseCurrentPopup();
		ClearStates();
		rv = ActionResult::Confirmed;
	}

	ImGui::SameLine();
	if (ImGui::Button(I18N_TEXT("Cancel", L10N_CANCEL))) {
		ImGui::CloseCurrentPopup();
		ClearStates();
		rv = ActionResult::Canceled;
	}

	return rv;
}

template <class T>
void ItemListEntries(ItemList<T>& list, int& selectedIdx) {
	constexpr bool kHasDescription = requires(T t) {
		t.GetDescription();
	};
	constexpr bool kHasEmail = requires(T t) {
		t.GetEmail();
	};
	constexpr bool kHasStock = requires(T t) {
		t.GetPrice();
	};
	constexpr bool kHasPrice = requires(T t) {
		t.GetPrice();
	};
	constexpr int kColumns = 1 /* Name column */ + kHasDescription + kHasEmail + kHasStock + kHasPrice;

	if (ImGui::BeginTable("", kColumns, ImGuiTableFlags_Borders)) {

		ImGui::TableSetupColumn(I18N_TEXT("Name", L10N_ITEM_COLUMN_NAME));
		if constexpr (kHasDescription) ImGui::TableSetupColumn(I18N_TEXT("Description", L10N_ITEM_COLUMN_DESCRIPTION));
		if constexpr (kHasEmail) ImGui::TableSetupColumn(I18N_TEXT("Email", L10N_ITEM_COLUMN_EMAIL));
		if constexpr (kHasStock) ImGui::TableSetupColumn(I18N_TEXT("Stock", L10N_ITEM_COLUMN_STOCK));
		if constexpr (kHasPrice) ImGui::TableSetupColumn(I18N_TEXT("Price", L10N_ITEM_COLUMN_PRICE));
		ImGui::TableHeadersRow();

		size_t idx = 0;
		for (auto& entry : list) {
			if (entry.IsInvalid()) {
				continue;
			}

			ImGui::TableNextRow();

			ImGui::TableNextColumn();
			if (ImGui::Selectable(entry.GetName().c_str(), selectedIdx == idx, ImGuiSelectableFlags_SpanAllColumns)) {
				selectedIdx = idx;
			}

			if constexpr (kHasDescription) {
				ImGui::TableNextColumn();
				ImGui::TextUnformatted(entry.GetDescription().c_str());
			}

			if constexpr (kHasEmail) {
				ImGui::TableNextColumn();
				ImGui::TextUnformatted(entry.GetEmail().c_str());
			}

			if constexpr (kHasStock) {
				ImGui::TableNextColumn();
				ImGui::Text("%d", entry.GetStock());
			}

			if constexpr (kHasPrice) {
				ImGui::TableNextColumn();
				// TODO format in dollars
				ImGui::Text("%d", entry.GetPrice());
			}

			idx++;
		}
		ImGui::EndTable();
	}
}

template <class T>
void ItemListEditor(ItemList<T>& list) {
	bool opened = true;
	static int selectedIdx = -1;
	static T* editingItem = nullptr;

	if (ImGui::Button(ICON_FA_PLUS " " I18N_TEXT("Add", L10N_ADD))) {
		ImGui::SetNextWindowCentered();
		ImGui::OpenPopup(I18N_TEXT("Add item", L10N_ITEM_ADD_DIALOG_TITLE));

		editingItem = &list.Insert("");
	}
	if (ImGui::BeginPopupModal(I18N_TEXT("Add item", L10N_ITEM_ADD_DIALOG_TITLE), &opened, ImGuiWindowFlags_AlwaysAutoResize)) {
		switch (ItemEditor(list, editingItem)) {
			case ActionResult::Confirmed:
				editingItem = nullptr;
				break;
			case ActionResult::Canceled:
				list.Remove(editingItem->GetId());
				editingItem = nullptr;
				break;
			default:
				break;
		}
		ImGui::EndPopup();
	}

	ImGui::SameLine();
	if (ImGui::Button(ICON_FA_EDIT " " I18N_TEXT("Edit", L10N_EDIT), selectedIdx == -1)) {
		ImGui::SetNextWindowCentered();
		ImGui::OpenPopup(I18N_TEXT("Edit item", L10N_ITEM_EDIT_DIALOG_TITLE));

		editingItem = list.Find(selectedIdx);
	}
	if (ImGui::BeginPopupModal(I18N_TEXT("Edit item", L10N_ITEM_EDIT_DIALOG_TITLE), &opened, ImGuiWindowFlags_AlwaysAutoResize)) {
		if (ItemEditor(list, editingItem) != ActionResult::Pending) {
			editingItem = nullptr;
		}
		ImGui::EndPopup();
	}

	ImGui::SameLine();
	if (ImGui::Button(ICON_FA_TRASH " " I18N_TEXT("Delete", L10N_DELETE), selectedIdx == -1)) {
		ImGui::SetNextWindowCentered();
		ImGui::OpenPopup(I18N_TEXT("Delete item", L10N_ITEM_DELETE_DIALOG_TITLE));

		list.Remove(selectedIdx);
	}
	if (ImGui::BeginPopupModal(I18N_TEXT("Delete item", L10N_ITEM_DELETE_DIALOG_TITLE), &opened, ImGuiWindowFlags_AlwaysAutoResize)) {
		ImGui::TextUnformatted(I18N_TEXT("Are you sure you want to delete this item?", L10N_ITEM_DELETE_DIALOG_MESSAGE));

		if (ImGui::Button(I18N_TEXT("Confirm", L10N_CONFIRM))) {
			ImGui::CloseCurrentPopup();
		}

		ImGui::SameLine();
		if (ImGui::Button(I18N_TEXT("Cancel", L10N_CANCEL))) {
			ImGui::CloseCurrentPopup();
		}

		ImGui::EndPopup();
	}

	ItemListEntries<T>(list, selectedIdx);
}
} // namespace CPLT_UNITY_ID

void UI::ItemsTab() {
	auto& gs = GlobalStates::GetInstance();

	if (ImGui::BeginTabBar("ItemViewTabs")) {
		if (ImGui::BeginTabItem(I18N_TEXT("Products", L10N_ITEM_CATEGORY_PRODUCT))) {
			CPLT_UNITY_ID::ItemListEditor(gs.GetCurrentProject()->Products);
			ImGui::EndTabItem();
		}
		if (ImGui::BeginTabItem(I18N_TEXT("Factories", L10N_ITEM_CATEGORY_FACTORY))) {
			CPLT_UNITY_ID::ItemListEditor(gs.GetCurrentProject()->Factories);
			ImGui::EndTabItem();
		}
		if (ImGui::BeginTabItem(I18N_TEXT("Customers", L10N_ITEM_CATEGORY_CUSTOMER))) {
			CPLT_UNITY_ID::ItemListEditor(gs.GetCurrentProject()->Customers);
			ImGui::EndTabItem();
		}
		ImGui::EndTabBar();
	}
}