class UsersViewController extends TimeCardsViewController {
	constructor(element) {
		super(element);

		this.userCells = { };

		//We store the project association rows in here for further management.
		//The association rows are the same for all users.
		this.projectRows = { };
		this.tariffFields = { };
		this.associationCheckboxes = { };

		TimeCards.dataManager.addDataListener("project", null, this.onProjectUpdate.bind(this));
		TimeCards.dataManager.addDataListener("user", null, this.onUserUpdate.bind(this));

		this.deleteUserDialog = new Dialog("<b>Are you sure you want to delete this employee?</b><br><br>They will no longer be able to log in. The recorded time periods will not be deleted.", this.onDeleteDialogReturned.bind(this), Dialog.BUTTONS_DESTRUCTIVE);
		this.resetPasswordDialog = new Dialog("<b>Are you sure you want to reset the password for this employee?</b><br><br>They will receive an email with a new temporary password and will be prompted to set a new password upon next login.", this.onResetPasswordDialogReturned.bind(this), {
			buttons: {
				cancel: {
					title: "Cancel"
				},
				ok: {
					title: "Reset Password",
					type: "default"
				}
			}
		});
	}

	viewDidLoad() {
		this.usersTableController.addEventListener("cellselected", this.onCellSelected.bind(this));

		this.newUserCell = new TableViewCell();
		this.newUserCell.titleLabel.innerText = "New Employee";

		//Give the report view a reference to the view controller.
		this.reportsViewController.usersViewController = this;
	}

	onUserUpdate(userId, user, sortedBefore) {
		if (!user) {
			//Handle the deleted user.
			if (!(userId in this.userCells)) {
				console.warn("A user deletion event has occurred, but the deleted user is not in the list of users of the UsersViewController.");
				return;
			}

			var userCell = this.userCells[userId];
			this.usersTableController.removeCell(userCell);
			delete this.userCells[userId];
		}
		else if (!(userId in this.userCells)) {
			//Handle the added user.
			var userCell = new UserCell();
			userCell.setData(user);

			this.usersTableController.addCell(userCell, (user.is_session_user ? 0 : 1), sortedBefore ? this.userCells[sortedBefore] : null);

			this.userCells[userId] = userCell;

			if (this.waitingForUserCreation) {
				this.waitingForUserCreation = false;

				this.usersTableController.selectCell(userCell);
			}
		}
		else {
			//Handle the changed user.
			var userCell = this.userCells[userId];
			userCell.setData(user);

			if (this.selectedUser && userId == this.selectedUser.user_id) {
				//Apply the new user data if the updated user is currently selected.
				this.setUserData(user);
			}

			//Re-add the cell to move it to the appropriate position in case the name has changed.
			this.usersTableController.addCell(userCell, (user.is_session_user ? 0 : 1), sortedBefore ? this.userCells[sortedBefore] : null);
		}

		//Store the last assigned projects of the session user.
		//We do this to detect projects that have been removed from the session user.
		//Removed projects will be reported to the data manager.
		//However, projects that the session user owns are not removed.
		if (user && user.is_session_user && user.projects) {
			if (this.lastAssignedProjectsForSessionUser) {
				//Go through the previously assigned projects and find ones that are no longer present in the new user object.
				for (var projectId in this.lastAssignedProjectsForSessionUser) {
					if (!(projectId in user.projects) && this.allProjects[projectId].id_user != user.user_id) {
						//Tell the data manager to remove this project locally.
						TimeCards.dataManager.deleteLocally("project", projectId);
					}
				}
			}

			this.lastAssignedProjectsForSessionUser = user.projects;
		}
	}

	onCellSelected(event) {
		if (!event.cell) {
			this.userSettingsSheet.style.display = "none";
			this.selectedUser = null;
		}
		else {
			//Hide the new user cell if another cell was selected.
			if (this.isNewUser && event.cell != this.newUserCell) {
				this.onDeleteButtonPressed(event);
			}

			this.setUserData(event.cell.user);

			this.userSettingsSheet.style.display = "";
		}
	}

	onFieldChanged(event) {
		event.stopPropagation();
		this.save();
	}

	onFormSubmitted(event) {
		event.preventDefault();
		event.stopPropagation();
		this.save();
	}

	save() {
		if (!this.editForm.reportValidity()) {
			return;
		}

		//Force username field to be lowercase.
		this.usernameField.value = this.usernameField.value.toLowerCase();

		var user = {
			full_name: this.fullNameField.value,
			username: this.usernameField.value,
			id_role: this.roleSelect.value,
			default_tariff: this.defaultTariffField.value,
			projects: this.gatherProjectAssociations()
		};

		if (this.isNewUser) {
			if (!this.waitingForUserCreation) {
				user.email = this.emailField.value;

				TimeCards.dataManager.store("user", user);
				this.waitingForUserCreation = true;
			}
		}
		else {
			user.email = this.emailField.value;
			TimeCards.dataManager.store("user", this.selectedUser.user_id, user);
		}

		//Update the project tariff field placeholders.
		for (var projectId in this.tariffFields) {
			this.tariffFields[projectId].placeholder = user.default_tariff;
		}
	}

	/**
	 * Returns an array of all the projects currently selected in the projects table with their tariffs (or null when none is specified).
	 */
	gatherProjectAssociations() {
		var checkboxes = this.projectsTableBody.querySelectorAll("input[type=\"checkbox\"]");

		var projects = { };
		for (var i = 0; i < checkboxes.length; i++) {
			var checkbox = checkboxes[i];

			if (checkbox.checked) {
				var tariff = this.tariffFields[checkbox.name].value;
				projects[checkbox.name] = tariff == "" ? null : tariff;
			}
		}

		return projects;
	}

	setUserData(user) {
		this.selectedUser = user;
		if (document.activeElement != this.fullNameField) {
			this.fullNameField.value = user.full_name;
		}
		if (document.activeElement != this.usernameField) {
			this.usernameField.value = user.username;
		}
		if (document.activeElement != this.emailField) {
			this.emailField.value = user.email;
		}
		if (document.activeElement != this.roleSelect) {
			this.roleSelect.value = user.id_role;
		}
		if (document.activeElement != this.defaultTariffField) {
			this.defaultTariffField.value = user.default_tariff;
		}

		//Apply the correct permission classes depending on whether this is the current user or not.
		this.fullNameField.classList.remove("available_w__user");
		this.fullNameField.classList.remove("available_w__user_samerole");
		this.fullNameField.classList.remove("available_w__user_all");
		this.usernameField.classList.remove("available_w__user");
		this.usernameField.classList.remove("available_w__user_samerole");
		this.usernameField.classList.remove("available_w__user_all");
		this.emailField.classList.remove("available_w__user");
		this.emailField.classList.remove("available_w__user_samerole");
		this.emailField.classList.remove("available_w__user_all");
		this.roleSelect.classList.remove("available_w__user");
		this.roleSelect.classList.remove("available_w__user_samerole");
		this.roleSelect.classList.remove("available_w__user_all");
		this.defaultTariffField.classList.remove("available_w__user");
		this.defaultTariffField.classList.remove("available_w__user_samerole");
		this.defaultTariffField.classList.remove("available_w__user_all");
		if (user.is_session_user) {
			this.fullNameField.classList.add("available_w__user");
			this.usernameField.classList.add("available_w__user");
			this.emailField.classList.add("available_w__user");
			this.roleSelect.classList.add("available_w__user");
			this.defaultTariffField.classList.add("available_w__user");
		}
		else if (user.id_role == Authentication.currentUser.id_role) {
			this.fullNameField.classList.add("available_w__user_samerole");
			this.usernameField.classList.add("available_w__user_samerole");
			this.emailField.classList.add("available_w__user_samerole");
			this.roleSelect.classList.add("available_w__user_samerole");
			this.defaultTariffField.classList.add("available_w__user_samerole");
		}
		else {
			this.fullNameField.classList.add("available_w__user_all");
			this.usernameField.classList.add("available_w__user_all");
			this.emailField.classList.add("available_w__user_all");
			this.roleSelect.classList.add("available_w__user_all");
			this.defaultTariffField.classList.add("available_w__user_all");
		}

		//Show or hide change and reset password buttons depending on session user or not.
		this.resetPasswordButton.parentNode.style.display = user.is_session_user ? "none" : "";
		this.changePasswordButton.parentNode.style.display = user.is_session_user ? "" : "none";

		//Set the project association checkbox and tariff field values.
		//Set all default tariff placeholders for the project associations.
		for (var projectId in this.tariffFields) {
			//The project is checked if the project is actually assigned or if the displaying user owns that project.
			var checked = (projectId in user.projects) || this.allProjects[projectId].id_user == user.user_id;
			this.setProjectAssociation(projectId, (projectId in user.projects) ? user.projects[projectId] : null, checked);
			this.tariffFields[projectId].placeholder = this.selectedUser.default_tariff;
		}

		//Hide the check all checkbox if it is the session user that is being displayed.
		this.assignAllBox.style.display = (user.is_session_user ? "none" : "");

		this.updateCheckAllCheckbox();

		//Show or hide the own user notification and prevent the editing of the own user and projects settings.
		this.ownRoleInformation.style.display = user.user_id == Authentication.currentUser.user_id ? "" : "none";
		this.deleteButton.disabled = user.user_id == Authentication.currentUser.user_id;
		this.ownUserDeletionInformation.style.display = user.user_id == Authentication.currentUser.user_id ? "" : "none";
		this.roleSelect.disabled = user.user_id == Authentication.currentUser.user_id;

		//TODO: Find out why this line exists and document it.
		this.updatePermissions();
	}

	setProjectAssociation(projectId, tariff = null, checked = false) {
		var associationRow = this.projectRows[projectId];

		//Update the tariff field value.
		var tariffField = associationRow.querySelector("#project-tariff-field__" + projectId);
		if (document.activeElement != tariffField) {
			tariffField.value = tariff;
		}
		tariffField.disabled = !checked;

		//Update the owner label.
		this.updateOwnerLabel(projectId);

		this.associationCheckboxes[projectId].checked = checked;

		//Hide the checkbox if it is the session user that is being displayed or if the project is owned by the displayed user.
		this.associationCheckboxes[projectId].style.display = ((this.selectedUser.is_session_user || this.allProjects[projectId].id_user == this.selectedUser.user_id) ? "none" : "");
	}

	/**
	 * Updates the owner label for the given project ID's association row.
	 */
	updateOwnerLabel(projectId) {
		var owner = TimeCards.dataManager.getEntity("user", this.allProjects[projectId].id_user);

		var ownerCell = this.projectRows[projectId].querySelector(".project-owner-cell");
		ownerCell.innerText = !owner ? "" : (owner.is_session_user ? "Own project" : "Owned by " + owner.full_name); //TODO: Localize this.
	}

	/**
	 * Updates the state of the check all checkbox.
	 */
	updateCheckAllCheckbox() {
		//Iterate over all rows and check the checkbox.
		var checkedCount = 0;
		var projectCount = Object.keys(this.associationCheckboxes).length;
		for (var projectId in this.associationCheckboxes) {
			checkedCount += this.associationCheckboxes[projectId].checked;
		}

		this.checkAllCheckbox.indeterminate = checkedCount > 0 && checkedCount < projectCount;
		this.checkAllCheckbox.checked = checkedCount == projectCount;
	}

	/**
	 * Called when a association checkbox has been changed.
	 */
	onAssociationCheckboxChanged(event) {
		//Forward to the general changed event and thereby save the user information.
		this.onFieldChanged(event);
	}

	/**
	 * Called when the assign all checkbox has been changed.
	 */
	onCheckAllCheckboxChanged(event) {
		//Check or uncheck all checkboxes.
		for (var projectId in this.associationCheckboxes) {
			this.associationCheckboxes[projectId].checked = this.checkAllCheckbox.checked;
		}

		//Save the changes.
		this.onFieldChanged(event);
	}

	onDeleteButtonPressed(event) {
		if (this.isNewUser) {
			this.isNewUser = false;
			this.usersTableController.removeCell(this.newUserCell);
		}
		else {
			this.deleteUserDialog.show();
		}
	}

	onDeleteDialogReturned(buttonId) {
		if (buttonId == "delete") {
			TimeCards.dataManager.store("user", this.selectedUser.user_id, null);
		}
	}

	onCreateButtonPressed(event) {
		this.isNewUser = true;

		this.newUserCell.user = {
			full_name: "",
			email: "",
			username: "",
			id_role: null,
			default_tariff: 0,
			projects: { }
		};

		this.usersTableController.addCell(this.newUserCell, 1);
		this.usersTableController.selectCell(this.newUserCell);

		this.fullNameField.focus();
	}

	onResetPasswordButtonPressed(event) {
		this.resetPasswordDialog.show();
	}

	onResetPasswordDialogReturned(buttonId) {
		if (buttonId != "ok") {
			return;
		}

		//Reset password by setting it to null.
		TimeCards.dataManager.store("user", this.selectedUser.user_id, {
			password: null
		}, function () {
			new Dialog("Password reset. An email with a temporary password has been sent to " + this.selectedUser.email + ".", null, Dialog.BUTTONS_OK_ONLY).show();
		}.bind(this));
	}

	onChangePasswordButtonPressed(event) {
		var changePasswordViewController = UIKit.getViewControllerById("change-password-view-controller");
		this.presentModalViewController(changePasswordViewController);
	}

	onProjectUpdate(projectId, project, sortedBefore) {
		if (!project) {
			//Handle the deleted project.
			if (!(projectId in this.projectRows)) {
				return;
			}

			this.projectsTableBody.removeChild(this.projectRows[projectId]);
			delete this.projectRows[projectId];
			delete this.tariffFields[projectId];
			delete this.associationCheckboxes[projectId];
		}
		else if (!(projectId in this.projectRows)) {
			//Handle the added project.

			//We store the projects in a local data object because we need the project data at several locations within this class.
			if (!this.allProjects) {
				this.allProjects = { };
			}
			this.allProjects[projectId] = project;

			//Create the new row for the association table.
			var associationRow = document.createElement("tr");
			associationRow.id = "project-association__" + projectId;

			//The checkbox cell.
			var projectCheckboxCell = document.createElement("td");
			associationRow.appendChild(projectCheckboxCell);

			//The checkbox.
			var projectCheckbox = document.createElement("input");
			projectCheckbox.type = "checkbox";
			if (this.selectedUser) {
				projectCheckbox.checked = (projectId in this.selectedUser.projects);
			}
			projectCheckbox.name = projectId;
			projectCheckbox.className = "available_w__project_user";
			projectCheckbox.addEventListener("change", this.onAssociationCheckboxChanged.bind(this));
			projectCheckboxCell.appendChild(projectCheckbox);

			this.associationCheckboxes[projectId] = projectCheckbox;

			//The left cell.
			var projectNameCell = document.createElement("td");
			projectNameCell.innerText = project.name;
			projectNameCell.style.paddingLeft = "0.25em";
			projectNameCell.className = "project-name-cell";
			associationRow.appendChild(projectNameCell);

			//The center cell.
			var centerCell = document.createElement("td");
			centerCell.className = "project-owner-cell require__multiuser";
			associationRow.appendChild(centerCell);

			//The right cell.
			var rightCell = document.createElement("td");
			rightCell.style.textAlign = "right";
			associationRow.appendChild(rightCell);

			var tariffField = document.createElement("input");
			tariffField.type = "number";
			if (this.createUser && (projectId in this.selectedUser.projects)) {
				tariffField.value = this.selectedUser.projects[projectId];
			}
			tariffField.id = "project-tariff-field__" + projectId;
			if (this.selectedUser) {
				tariffField.placeholder = this.selectedUser.default_tariff;
			}
			tariffField.className = "tariff-field available__multiuser require__project_user_tariff available_w__project_user_tariff";
			tariffField.addEventListener("change", this.onFieldChanged.bind(this));
			Validation.addAttributes(tariffField, "project_user", "tariff");
			rightCell.appendChild(tariffField);
			this.tariffFields[projectId] = tariffField;

			var perHourLabel = document.createElement("label");
			perHourLabel.setAttribute("for", "project-tariff-field__" + projectId);
			perHourLabel.innerText = "/ h";
			perHourLabel.className = "require__project_user_tariff";
			rightCell.appendChild(perHourLabel);

			this.projectsTableBody.insertBefore(associationRow, sortedBefore ? this.projectRows[sortedBefore] : null);

			this.projectRows[projectId] = associationRow;
		}
		else {
			this.allProjects[projectId] = project;

			//Handle the changed project.
			this.projectRows[projectId].querySelector(".project-name-cell").innerText = project.name;

			//Decide upon the placement of the changed association row. This is because we want the sorting to stay integer when the name changes.
			this.projectsTableBody.insertBefore(this.projectRows[projectId], sortedBefore ? this.projectRows[sortedBefore] : null);

			//Update the owner label.
			this.updateOwnerLabel(projectId);
		}
	}
}
UIKit.registerViewControllerType(UsersViewController);