async function handleResponse(response) {
    const raw = await response.text();

    // Try to parse JSON safely
    try {
        return JSON.parse(raw);
    } catch (e) {
        throw new Error("Invalid JSON response:\n" + raw);
    }
}


// ======================
// NER
// ======================
async function runNER() {
    try {
        const text = document.getElementById("text").value.trim();

        if (!text) {
            document.getElementById("output").textContent = "Please enter text.";
            return;
        }

        const response = await fetch("/predict", {
            method: "POST",
            headers: { "Content-Type": "application/json" },
            body: JSON.stringify({ text: text, mode: "1" })
        });

        const data = await handleResponse(response);

        if (data.error) {
            document.getElementById("output").textContent =
                "NER Backend Error:\n" + data.error;
            return;
        }

        if (!data.resp || data.resp.length === 0) {
            document.getElementById("output").textContent =
                "No NER results.";
            return;
        }

        // pretty print
        document.getElementById("output").textContent =
            JSON.stringify(data.resp, null, 2);

    } catch (err) {
        document.getElementById("output").textContent =
            "NER Error: " + err.message;
    }
}


// ======================
// Relation Extraction
// ======================
async function runRE() {
    try {
        const text = document.getElementById("text").value.trim();

        if (!text) {
            document.getElementById("output").textContent = "Please enter text.";
            return;
        }

        const response = await fetch("/predict_re", {
            method: "POST",
            headers: { "Content-Type": "application/json" },
            body: JSON.stringify({ text: text })
        });

        const data = await handleResponse(response);

        if (data.error) {
            document.getElementById("output").textContent =
                "RE Backend Error:\n" + data.error;
            return;
        }

        if (!data.resp || data.resp.length === 0) {
            document.getElementById("output").textContent =
                "No relations found.";
            return;
        }

        // =========================
        // CLEAN JSON OUTPUT FORMAT
        // =========================
        const formattedList = data.resp.map(r => ({
            Subject: {
                Type: r.Subject.Type,
                Label: r.Subject.Label
            },
            Relation: r.Relation,
            Object: {
                Type: r.Object.Type,
                Label: r.Object.Label
            },
            Confidence: r.Confidence
        }));

        document.getElementById("output").textContent =
            JSON.stringify(formattedList, null, 2);

    } catch (err) {
        document.getElementById("output").textContent =
            "RE Error: " + err.message;
    }
}