/**
 * script.js – BIBB-Thesaurus Normdatenverwaltung
 * Erstellt: 2021/07/01 (Roland)
 * Überarbeitet: 2026/02 – Bugfixes, Bereinigung, Fehlertoleranz
 */

// ============================================================
// HILFSFUNKTIONEN
// ============================================================

/**
 * Zeigt eine Fehlermeldung in einem Alert-Element an.
 * @param {string} elementId  ID des Alert-Divs
 * @param {string} msg        Anzuzeigende Nachricht
 * @param {string} level      Bootstrap-Level: 'danger' | 'warning' | 'success'
 */
function showAlert(elementId, msg, level) {
    const a = document.getElementById(elementId);
    if (!a) return;
    a.className = 'alert alert-' + (level || 'danger');
    a.textContent = msg;
    a.style.display = 'block';
}

function hideAlert(elementId) {
    const a = document.getElementById(elementId);
    if (!a) return;
    a.className = 'alert';
    a.textContent = '';
    a.style.display = 'none';
}

function setFieldsDisabled(fields, disabled) {
    fields.forEach(id => {
        const el = document.getElementById(id);
        if (el) el.disabled = disabled;
    });
}

// ============================================================
// SUCHE
// ============================================================

function Search() {
    const search_string = $("#search_text").val().trim();

    if (search_string === "") {
        alert('Bitte Suchkriterien eingeben!');
        return;
    }

    $.post("ajax/search.php", { search_string }, function(data) {
        $(".records_content").html(data);
        $("#search_text").val("");
    }).fail(function() {
        alert('Fehler bei der Suche. Bitte erneut versuchen.');
    });
}

// ============================================================
// NEUES SCHLAGWORT
// ============================================================

function newSubjectShow() {
    const editableFields = ["new_term", "new_type", "new_detailtype", "new_classification", "new_scopenote"];

    document.getElementById("newSubjectSave").style.display         = 'inline';
    document.getElementById("newSubjectDismiss").style.display      = 'inline';
    document.getElementById("SubjectModifySave").style.display      = 'none';
    document.getElementById("new_relation_label").style.display     = 'none';
    document.getElementById("newRelationSubjectDismiss").style.display = 'none';
    document.getElementById("relation_table").style.display         = 'none';

    setFieldsDisabled(editableFields, false);
    hideAlert("errorNewSubject");

    $("#new_term").val("");
    $("#new_classification").val("");
    $("#new_scopenote").val("");

    showRelations(0, 0, 0);
    $("#NewSubjectModal").modal("show");
}

function CreateNewEntry() {
    const term           = $("#new_term").val().trim();
    const type           = $("#new_type").val().trim();
    const detailtype     = $("#new_detailtype").val().trim();
    const classification = $("#new_classification").val().trim();
    const scopenote      = $("#new_scopenote").val().trim();

    if (term.length === 0) {
        showAlert("errorNewSubject", "Bitte Schlagwort eingeben!", "danger");
        return;
    }

    hideAlert("errorNewSubject");

    $.post("ajax/newSubject.php", { term, type, detailtype, classification, scopenote },
        function(data) {
            const dt = JSON.parse(data);
            if (dt.status === 200) {
                const editableFields = ["new_term", "new_type", "new_detailtype", "new_classification", "new_scopenote"];
                setFieldsDisabled(editableFields, true);

                document.getElementById("newSubjectSave").style.display              = 'none';
                document.getElementById("newSubjectDismiss").style.display           = 'none';
                document.getElementById("new_relation_label").style.display          = 'block';
                document.getElementById("newRelationSubjectDismiss").style.display   = 'inline';

                showAlert("errorNewSubject", "Neues Schlagwort aufgenommen", "success");
                showRelations(dt.Anchor, dt.Entry, dt.Linking);
            } else {
                showAlert("errorNewSubject", dt.message || "Unbekannter Fehler", "danger");
            }
        }
    ).fail(function() {
        showAlert("errorNewSubject", "Serverfehler beim Anlegen des Eintrags.", "danger");
    });
}

// ============================================================
// RELATIONEN
// ============================================================

function showRelations(Anchor, Entry, Linking) {
    $.get("ajax/getRelations.php", { anchorID: Anchor },
        function(data, status) {
            if (status === "success") {
                $(".new_modal_content").html(JSON.parse(data));
                document.getElementById("relation_table").style.display = 'block';
                $("#NewSubjectModal").modal("show");
            }
        }
    ).fail(function() {
        console.error("Fehler beim Laden der Relationen für AnchorID:", Anchor);
    });
}

function CreateNewRelation(AnchorID) {
    const relationType = document.getElementById("new_relationtype").value;
    const relationText = document.getElementById("search_relation").value;
    const relationID   = relationText.substring(
        relationText.lastIndexOf(":") + 2,
        relationText.lastIndexOf(")")
    ).trim();

    if (!relationID) {
        showAlert("errorNewSubject", "Kein gültiger Relationseintrag ausgewählt.", "warning");
        return;
    }

    $.post("ajax/writeNewRelation.php", { AnchorID, relationType, relationID },
        function(data, status) {
            if (status === "success") {
                showAlert("errorNewSubject", "Neue Relation aufgenommen", "success");
                showRelations(AnchorID, 0, 0);
            }
        }
    ).fail(function() {
        showAlert("errorNewSubject", "Fehler beim Speichern der Relation.", "danger");
    });
}

function DeleteRelation(AnchorID, LinkingID) {
    $.post("ajax/deleteRelation.php", { AnchorID, LinkingID },
        function(data, status) {
            if (status === "success") {
                showAlert("errorNewSubject", "Relation gelöscht", "success");
                showRelations(AnchorID, 0, 0);
            }
        }
    ).fail(function() {
        showAlert("errorNewSubject", "Fehler beim Löschen der Relation.", "danger");
    });
}

// ============================================================
// EINTRAG BEARBEITEN / LÖSCHEN
// ============================================================

function DeleteTerm(AnchorID) {
    $.post("ajax/deleteTerm.php", { AnchorID: AnchorID[0] },
        function(data, status) {
            if (status !== "success") {
                alert(JSON.parse(data));
            }
        }
    ).fail(function() {
        alert("Fehler beim Löschen des Eintrags.");
    });
}

function ModifyTerm(AnchorID) {
    $("#ID").val(AnchorID[0]);

    $.get("ajax/getAuthorityDataRaw.php", { id: AnchorID[0] },
        function(data, status) {
            if (status === "success") {
                const dt = JSON.parse(data).rows[0];
                if (!dt) return;
                $("#new_term").val(dt.Text);
                $("#new_id").val(dt.ID);
                $("#new_detailtype").val(dt.DetailType);
                $("#new_classification").val(dt.Classification);
                $("#new_descriptor").val(dt.Descriptor);
                $("#new_type").val(dt.Type);
                $("#new_scopenote").val(dt.Scopenote);
            }
        }
    );

    $.get("ajax/getRelations.php", { anchorID: AnchorID[0] },
        function(data, status) {
            if (status === "success") {
                $(".new_modal_content").html(JSON.parse(data));
                document.getElementById("relation_table").style.display         = 'block';
                document.getElementById("newSubjectSave").style.display         = 'none';
                document.getElementById("newSubjectDismiss").style.display      = 'inline';
                document.getElementById("SubjectModifySave").style.display      = 'inline';
                document.getElementById("newRelationSubjectDismiss").style.display = 'none';
                $("#NewSubjectModalHeadline").val("Schlagwort ändern");
                $("#NewSubjectModal").modal("show");
            }
        }
    );
}

function UpdateEntry(authType) {
    const AnchorID       = $("#ID").val();
    const term           = $("#new_term").val().trim();
    const type           = $("#new_type").val().trim();
    const detailtype     = $("#new_detailtype").val().trim();
    const classification = $("#new_classification").val().trim();
    const scopenote      = $("#new_scopenote").val().trim();

    if (term.length === 0) {
        showAlert("errorNewSubject", "Bitte Schlagwort eingeben!", "danger");
        return;
    }

    hideAlert("errorNewSubject");

    $.post("ajax/UpdateTerm.php", { AnchorID, authType, term, type, detailtype, classification, scopenote },
        function(data, status) {
            if (status === "success") {
                document.getElementById("relation_table").style.display         = 'block';
                document.getElementById("newSubjectSave").style.display         = 'none';
                document.getElementById("newSubjectDismiss").style.display      = 'inline';
                document.getElementById("SubjectModifySave").style.display      = 'none';
                document.getElementById("newRelationSubjectDismiss").style.display = 'none';
                showAlert("errorNewSubject", "Schlagwort geändert", "success");
                $("#NewSubjectModalHeadline").val("Schlagwort ändern");
                $("#NewSubjectModal").modal("show");
            }
        }
    ).fail(function() {
        showAlert("errorNewSubject", "Fehler beim Speichern des Eintrags.", "danger");
    });
}

// ============================================================
// STATISTIK
// ============================================================

function generateStatistics() {
    const startVal = document.getElementById("startPeriod").value;
    const endVal   = document.getElementById("endPeriod").value;

    if (!startVal || !endVal) {
        showAlert("errorStatistics", "Bitte Start- und Endtermin angeben.", "warning");
        return;
    }
    if (startVal > endVal) {
        showAlert("errorStatistics", "Starttermin darf nicht nach dem Endtermin liegen.", "warning");
        return;
    }

    hideAlert("errorStatistics");

    const content = $("#records_content");

    // Spinner oberhalb des Ergebnisbereichs anzeigen, records_content NICHT anfassen
    $("#statisticsSpinner").remove();
    $("#records_content").before(
        '<div id="statisticsSpinner" class="text-center my-3">'
        + '<div class="spinner-border text-primary" role="status">'
        + '<span class="visually-hidden">Lädt...</span></div></div>'
    );
    $("#records_content").hide();

    $.ajax({
        url:      "ajax/getStatistics.php",
        method:   "GET",
        dataType: "json",
        data: {
            dateStart: (startVal + " 00:00:00").trim(),
            dateEnd:   (endVal   + " 23:59:59").trim()
        },
        success: function(data) {
            $("#statisticsSpinner").remove();
            if (data.status === 200) {
                document.getElementById("statisticsBody").innerHTML       = data.rows;
                document.getElementById("statisticsFoot").innerHTML       = data.foot;
                document.getElementById("statisticsZeitraum").textContent = data.zeitraum;
                content.show();
            } else {
                showAlert("errorStatistics", data.message || "Unbekannter Fehler.", "warning");
            }
        },
        error: function(xhr, status, error) {
            $("#statisticsSpinner").remove();
            showAlert("errorStatistics", "Serverfehler: " + (error || status), "danger");
        }
    });
}

// ============================================================
// HILFSFUNKTIONEN UI
// ============================================================

function RecordContentHide() {
    const el = document.getElementById("records_content");
    el.style.display = 'none';
    el.textContent   = '';
}

function DisplayEnterDateSelection() {
    document.getElementById("QueryStatistics").style.display = 'block';
}