$(function () {
    const contentSection = document.querySelector('.content');
    const SERVICE_STATUS_URL = contentSection.dataset.serviceStatusUrl;
    const BULK_REMOVE_URL = contentSection.dataset.bulkRemoveUrl;
    const REMOVE_USER_URL_TEMPLATE = contentSection.dataset.removeUserUrlTemplate;
    const BULK_ADD_URL = contentSection.dataset.bulkAddUrl;
    const ADD_USER_URL = contentSection.dataset.addUserUrl;
    const EDIT_USER_URL_TEMPLATE = contentSection.dataset.editUserUrlTemplate;
    const RESET_USER_URL_TEMPLATE = contentSection.dataset.resetUserUrlTemplate;
    const USER_URI_URL_TEMPLATE = contentSection.dataset.userUriUrlTemplate;
    const BULK_URI_URL = contentSection.dataset.bulkUriUrl;
    const USERS_BASE_URL = contentSection.dataset.usersBaseUrl;
    const GET_USER_URL_TEMPLATE = contentSection.dataset.getUserUrlTemplate;

    const usernameRegex = /^[a-zA-Z0-9_]+$/;
    const passwordRegex = /^[a-zA-Z0-9]+$/;
    let cachedUserData = [];

    function setCookie(name, value, days) {
        let expires = "";
        if (days) {
            const date = new Date();
            date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
            expires = "; expires=" + date.toUTCString();
        }
        document.cookie = name + "=" + (value || "") + expires + "; path=/";
    }

    function getCookie(name) {
        const nameEQ = name + "=";
        const ca = document.cookie.split(';');
        for (let i = 0; i < ca.length; i++) {
            let c = ca[i];
            while (c.charAt(0) === ' ') c = c.substring(1, c.length);
            if (c.indexOf(nameEQ) === 0) return c.substring(nameEQ.length, c.length);
        }
        return null;
    }

    function generatePassword(length = 32) {
        const chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
        let result = '';
        for (let i = 0; i < length; i++) {
            result += chars.charAt(Math.floor(Math.random() * chars.length));
        }
        return result;
    }

    function checkIpLimitServiceStatus() {
        $.getJSON(SERVICE_STATUS_URL)
            .done(data => {
                if (data.hysteria_iplimit === true) {
                    $('.requires-iplimit-service').show();
                }
            })
            .fail(() => console.error('Error fetching IP limit service status.'));
    }

    function validateUsername(inputElement, errorElement) {
        const username = $(inputElement).val();
        const isValid = usernameRegex.test(username);
        $(errorElement).text(isValid ? "" : "Usernames can only contain letters, numbers, and underscores.");
        $(inputElement).closest('form').find('button[type="submit"]').prop('disabled', !isValid);
    }
    
    function validatePassword(inputElement, errorElement) {
        const password = $(inputElement).val();
        // The password is valid if it's empty (no change) OR it matches the alphanumeric regex.
        const isValid = password === '' || passwordRegex.test(password);
        $(errorElement).text(isValid ? "" : "Password can only contain letters and numbers.");
        $('#editSubmitButton').prop('disabled', !isValid);
    }
    
    $('#editPassword').on('input', function() {
        validatePassword(this, '#editPasswordError');
    });

    $('#addUsername, #addBulkPrefix').on('input', function() {
        validateUsername(this, `#${this.id}Error`);
    });

    $(".filter-button").on("click", function (e) {
        e.preventDefault();
        const filter = $(this).data("filter");
        $("#selectAll").prop("checked", false);
        $("#userTable tbody tr.user-main-row").each(function () {
            let showRow;
            switch (filter) {
                case "on-hold":    showRow = $(this).find("td:eq(3) i").hasClass("text-warning"); break;
                case "online":     showRow = $(this).find("td:eq(3) i").hasClass("text-success"); break;
                case "enable":     showRow = $(this).find("td:eq(8) i").hasClass("text-success"); break;
                case "disable":    showRow = $(this).find("td:eq(8) i").hasClass("text-danger"); break;
                default:           showRow = true;
            }
            $(this).toggle(showRow).find(".user-checkbox").prop("checked", false);
            if (!showRow) {
                $(this).next('tr.user-details-row').hide();
            }
        });
    });

    $("#selectAll").on("change", function () {
        $("#userTable tbody tr.user-main-row:visible .user-checkbox").prop("checked", this.checked);
    });

    $("#deleteSelected").on("click", function () {
        const selectedUsers = $(".user-checkbox:checked").map((_, el) => $(el).val()).get();
        if (selectedUsers.length === 0) {
            return Swal.fire("Warning!", "Please select at least one user to delete.", "warning");
        }
        Swal.fire({
            title: "Are you sure?",
            html: `This will delete: <b>${selectedUsers.join(", ")}</b>.<br>This action cannot be undone!`,
            icon: "warning",
            showCancelButton: true,
            confirmButtonColor: "#d33",
            confirmButtonText: "Yes, delete them!",
        }).then((result) => {
            if (!result.isConfirmed) return;

            if (selectedUsers.length > 1) {
                $.ajax({
                    url: BULK_REMOVE_URL,
                    method: "POST",
                    contentType: "application/json",
                    data: JSON.stringify({ usernames: selectedUsers })
                })
                .done(() => Swal.fire("Success!", "Selected users have been deleted.", "success").then(() => location.reload()))
                .fail((err) => Swal.fire("Error!", err.responseJSON?.detail || "An error occurred while deleting users.", "error"));
            } else {
                const singleUrl = REMOVE_USER_URL_TEMPLATE.replace('U', selectedUsers[0]);
                $.ajax({
                    url: singleUrl,
                    method: "DELETE"
                })
                .done(() => Swal.fire("Success!", "The user has been deleted.", "success").then(() => location.reload()))
                .fail((err) => Swal.fire("Error!", err.responseJSON?.detail || "An error occurred while deleting the user.", "error"));
            }
        });
    });

    $("#addUserForm, #addBulkUsersForm").on("submit", function (e) {
        e.preventDefault();
        const form = $(this);
        const isBulk = form.attr('id') === 'addBulkUsersForm';
        const url = isBulk ? BULK_ADD_URL : ADD_USER_URL;
        const button = form.find('button[type="submit"]').prop('disabled', true);
        
        const formData = new FormData(this);
        const jsonData = Object.fromEntries(formData.entries());

        jsonData.unlimited = jsonData.unlimited === 'on';

        $.ajax({
            url: url,
            method: "POST",
            contentType: "application/json",
            data: JSON.stringify(jsonData),
        })
        .done(res => Swal.fire("Success!", res.detail, "success").then(() => location.reload()))
        .fail(err => Swal.fire("Error!", err.responseJSON?.detail || "An error occurred.", "error"))
        .always(() => button.prop('disabled', false));
    });

    $("#editUserModal").on("show.bs.modal", function (event) {
        const user = $(event.relatedTarget).data("user");
        const dataRow = $(event.relatedTarget).closest("tr.user-main-row");
        const url = GET_USER_URL_TEMPLATE.replace('U', user);

        const trafficText = dataRow.find("td:eq(4)").text();
        const expiryText = dataRow.find("td:eq(6)").text();
        const note = dataRow.data('note');
        
        $('#editPasswordError').text('');
        $('#editSubmitButton').prop('disabled', false);

        $("#originalUsername").val(user);
        $("#editUsername").val(user);
        $("#editTrafficLimit").val(parseFloat(trafficText.split('/')[1]) || 0);
        $("#editExpirationDays").val(parseInt(expiryText) || 0);
        $("#editNote").val(note || '');
        $("#editBlocked").prop("checked", !dataRow.find("td:eq(8) i").hasClass("text-success"));
        $("#editUnlimitedIp").prop("checked", dataRow.find(".unlimited-ip-cell i").hasClass("text-primary"));
    
        const passwordInput = $("#editPassword");
        passwordInput.val("Loading...").prop("disabled", true);
    
        $.getJSON(url)
            .done(userData => {
                passwordInput.val(userData.password || '');
                validatePassword('#editPassword', '#editPasswordError');
            })
            .fail(() => {
                passwordInput.val("").attr("placeholder", "Failed to load password");
            })
            .always(() => {
                passwordInput.prop("disabled", false);
            });
    });
    
    $('#editUserModal').on('click', '#generatePasswordBtn', function() {
        $('#editPassword').val(generatePassword()).trigger('input');
    });
    
    $("#editUserForm").on("submit", function (e) {
        e.preventDefault();
        const button = $("#editSubmitButton").prop("disabled", true);
        const originalUsername = $("#originalUsername").val();
        const url = EDIT_USER_URL_TEMPLATE.replace('U', originalUsername);

        const formData = new FormData(this);
        const jsonData = Object.fromEntries(formData.entries());
        jsonData.blocked = jsonData.blocked === 'on';
        jsonData.unlimited_ip = jsonData.unlimited_ip === 'on';

        $.ajax({
            url: url,
            method: "PATCH",
            contentType: "application/json",
            data: JSON.stringify(jsonData),
        })
        .done(res => Swal.fire("Success!", res.detail, "success").then(() => location.reload()))
        .fail(err => Swal.fire("Error!", err.responseJSON?.detail, "error"))
        .always(() => button.prop('disabled', false));
    });

    $("#userTable").on("click", ".reset-user, .delete-user", function () {
        const button = $(this);
        const username = button.data("user");
        const isDelete = button.hasClass("delete-user");
        const action = isDelete ? "delete" : "reset";
        const urlTemplate = isDelete ? REMOVE_USER_URL_TEMPLATE : RESET_USER_URL_TEMPLATE;

        Swal.fire({
            title: `Are you sure you want to ${action}?`,
            html: `This will ${action} user <b>${username}</b>.`,
            icon: "warning",
            showCancelButton: true,
            confirmButtonColor: "#d33",
            confirmButtonText: `Yes, ${action} it!`,
        }).then((result) => {
            if (!result.isConfirmed) return;
            $.ajax({
                url: urlTemplate.replace("U", encodeURIComponent(username)),
                method: isDelete ? "DELETE" : "GET",
            })
            .done(res => Swal.fire("Success!", res.detail, "success").then(() => location.reload()))
            .fail(() => Swal.fire("Error!", `Failed to ${action} user.`, "error"));
        });
    });

    $("#qrcodeModal").on("show.bs.modal", function (event) {
        const username = $(event.relatedTarget).data("username");
        const qrcodesContainer = $("#qrcodesContainer").empty();
        const url = USER_URI_URL_TEMPLATE.replace("U", encodeURIComponent(username));
        $.getJSON(url, response => {
            [
                { type: "IPv4", link: response.ipv4 },
                { type: "IPv6", link: response.ipv6 },
                { type: "Normal-SUB", link: response.normal_sub }
            ].forEach(config => {
                if (!config.link) return;
                const qrId = `qrcode-${config.type}`;
                const card = $(`<div class="card d-inline-block m-2"><div class="card-body"><div id="${qrId}" class="mx-auto" style="cursor: pointer;"></div><div class="mt-2 text-center small text-body font-weight-bold">${config.type}</div></div></div>`);
                qrcodesContainer.append(card);
                new QRCodeStyling({ width: 200, height: 200, data: config.link, margin: 2 }).append(document.getElementById(qrId));
                card.on("click", () => navigator.clipboard.writeText(config.link).then(() => Swal.fire({ icon: "success", title: `${config.type} link copied!`, showConfirmButton: false, timer: 1200 })));
            });
        }).fail(() => Swal.fire("Error!", "Failed to fetch user configuration.", "error"));
    });
    
    $("#showSelectedLinks").on("click", function () {
        const selectedUsers = $(".user-checkbox:checked").map((_, el) => $(el).val()).get();
        if (selectedUsers.length === 0) {
            return Swal.fire("Warning!", "Please select at least one user.", "warning");
        }

        Swal.fire({ title: 'Fetching links...', text: 'Please wait.', allowOutsideClick: false, didOpen: () => Swal.showLoading() });
        
        $.ajax({
            url: BULK_URI_URL,
            method: 'POST',
            contentType: 'application/json',
            data: JSON.stringify({ usernames: selectedUsers }),
        }).done(results => {
            Swal.close();
            cachedUserData = results;
            
            const fetchedCount = results.length;
            const failedCount = selectedUsers.length - fetchedCount;
            
            if (failedCount > 0) {
               Swal.fire('Warning', `Could not fetch info for ${failedCount} user(s), but others were successful.`, 'warning');
            }
            
            if (fetchedCount > 0) {
                const hasIPv4 = cachedUserData.some(user => user.ipv4);
                const hasIPv6 = cachedUserData.some(user => user.ipv6);
                const hasNormalSub = cachedUserData.some(user => user.normal_sub);
                const hasNodes = cachedUserData.some(user => user.nodes && user.nodes.length > 0);

                $("#extractIPv4").closest('.form-check-inline').toggle(hasIPv4);
                $("#extractIPv6").closest('.form-check-inline').toggle(hasIPv6);
                $("#extractNormalSub").closest('.form-check-inline').toggle(hasNormalSub);
                $("#extractNodes").closest('.form-check-inline').toggle(hasNodes);

                $("#linksTextarea").val('');
                $("#showLinksModal").modal("show");
            } else {
               Swal.fire('Error', `Could not fetch info for any of the selected users.`, 'error');
            }
        }).fail(() => Swal.fire('Error!', 'An error occurred while fetching the links.', 'error'));
    });

    $("#extractLinksButton").on("click", function () {
        const allLinks = [];
        const linkTypes = {
            ipv4: $("#extractIPv4").is(":checked"),
            ipv6: $("#extractIPv6").is(":checked"),
            normal_sub: $("#extractNormalSub").is(":checked"),
            nodes: $("#extractNodes").is(":checked")
        };

        cachedUserData.forEach(user => {
            if (linkTypes.ipv4 && user.ipv4) {
                allLinks.push(user.ipv4);
            }
            if (linkTypes.ipv6 && user.ipv6) {
                allLinks.push(user.ipv6);
            }
            if (linkTypes.normal_sub && user.normal_sub) {
                allLinks.push(user.normal_sub);
            }
            if (linkTypes.nodes && user.nodes && user.nodes.length > 0) {
                user.nodes.forEach(node => {
                    if (node.uri) {
                        allLinks.push(node.uri);
                    }
                });
            }
        });

        $("#linksTextarea").val(allLinks.join('\n'));
    });
    
    $("#copyExtractedLinksButton").on("click", () => {
        const links = $("#linksTextarea").val();
        if (!links) {
            return Swal.fire({ icon: "info", title: "Nothing to copy!", text: "Please extract some links first.", showConfirmButton: false, timer: 1500 });
        }
        navigator.clipboard.writeText(links)
            .then(() => Swal.fire({ icon: "success", title: "Links copied!", showConfirmButton: false, timer: 1200 }));
    });

    function filterUsers() {
        const searchText = $("#searchInput").val().toLowerCase();
        $("#userTable tbody tr.user-main-row").each(function () {
            const username = $(this).find("td:eq(2)").text().toLowerCase();
            const note = $(this).data("note").toLowerCase();
            const isVisible = username.includes(searchText) || note.includes(searchText);
            $(this).toggle(isVisible);
            if (!isVisible) {
                $(this).next('tr.user-details-row').hide();
            }
        });
    }

    $('#userTable').on('click', '.toggle-details-btn', function() {
        const $this = $(this);
        const icon = $this.find('i');
        const detailsRow = $this.closest('tr.user-main-row').next('tr.user-details-row');

        detailsRow.toggle();

        if (detailsRow.is(':visible')) {
            icon.removeClass('fa-plus').addClass('fa-minus');
        } else {
            icon.removeClass('fa-minus').addClass('fa-plus');
        }
    });
    
    $('#addUserModal').on('show.bs.modal', function () {
        $('#addUserForm, #addBulkUsersForm').trigger('reset');
        $('#addUsernameError, #addBulkPrefixError').text('');
        Object.assign(document.getElementById('addTrafficLimit'), {value: 30});
        Object.assign(document.getElementById('addExpirationDays'), {value: 30});
        Object.assign(document.getElementById('addBulkTrafficLimit'), {value: 30});
        Object.assign(document.getElementById('addBulkExpirationDays'), {value: 30});
        $('#addSubmitButton, #addBulkSubmitButton').prop('disabled', true);
        $('#addUserModal a[data-toggle="tab"]').first().tab('show');
    });

    $("#searchButton").on("click", filterUsers);
    $("#searchInput").on("keyup", filterUsers);

    function initializeLimitSelector() {
        const savedLimit = getCookie('limit') || '50';
        $('#limit-select').val(savedLimit);

        $('#limit-select').on('change', function() {
            const newLimit = $(this).val();
            setCookie('limit', newLimit, 365);
            window.location.href = USERS_BASE_URL;
        });
    }
    
    initializeLimitSelector();
    checkIpLimitServiceStatus();
    $('[data-toggle="tooltip"]').tooltip();
});