let currentUser = null;
let currentPrescriptions = [];

document.addEventListener('DOMContentLoaded', () => {
    console.log('DOM fully loaded, initializing event listeners');

    document.getElementById('showSignupLink').addEventListener('click', (e) => {
        e.preventDefault();
        console.log('Show signup link clicked');
        showSignup();
    });

    document.getElementById('showLoginLink').addEventListener('click', (e) => {
        e.preventDefault();
        console.log('Show login link clicked');
        showLogin();
    });

    document.getElementById('signupRole').addEventListener('change', function() {
        console.log('Signup role changed to:', this.value);
        const isPatient = this.value === 'Patient';
        document.getElementById('signupAllergies').disabled = !isPatient;
        document.getElementById('signupSymptoms').disabled = !isPatient;
    });

    document.getElementById('loginButton').addEventListener('click', (e) => {
        e.preventDefault();
        console.log('Login button clicked');
        login();
    });

    document.getElementById('doctorLogout').addEventListener('click', logout);
    document.getElementById('patientLogout').addEventListener('click', logout);
    document.getElementById('pharmacyLogout').addEventListener('click', logout);

    document.getElementById('mostPrescribedButton').addEventListener('click', fetchMostPrescribed);
    document.getElementById('viewPrescriptionsButton').addEventListener('click', fetchPrescriptions);
    document.getElementById('findPharmaciesButton').addEventListener('click', findPharmacies);
    document.getElementById('checkRemindersButton').addEventListener('click', fetchRefillReminders);
    document.getElementById('viewOrdersButton').addEventListener('click', fetchOrders);
    document.getElementById('checkLowStockButton').addEventListener('click', fetchLowStock);
    document.getElementById('medicineIdStock').addEventListener('change', toggleNewTabletFields);
    document.getElementById('prescriptionId').addEventListener('change', displayPrescriptionPrice);
    document.getElementById('paymentMethod').addEventListener('change', updateButtonStates);
    document.getElementById('upiApp').addEventListener('change', updateButtonStates);
    document.getElementById('prescriptionId').addEventListener('change', updateButtonStates);
    document.getElementById('pharmacyId').addEventListener('change', updateButtonStates);
    document.getElementById('orderForm').addEventListener('submit', (e) => {
        e.preventDefault();
        placeOrder();
    });

    // Delegated event listener for confirmPayment
    document.addEventListener('click', (e) => {
        if (e.target.id === 'confirmPayment') {
            console.log('Confirm Payment button clicked (delegated)');
            confirmPayment();
        }
    });
});

function showSignup() {
    document.getElementById('loginSection').classList.add('d-none');
    document.getElementById('signupSection').classList.remove('d-none');
}

function showLogin() {
    document.getElementById('signupSection').classList.add('d-none');
    document.getElementById('loginSection').classList.remove('d-none');
    hideDashboards();
    document.getElementById('loginSection').querySelector('form')?.reset();
    console.log('Login form reset and displayed');
}

function hideDashboards() {
    document.getElementById('doctorDashboard').classList.add('d-none');
    document.getElementById('patientDashboard').classList.add('d-none');
    document.getElementById('pharmacyDashboard').classList.add('d-none');
}

function logout() {
    console.log('Logout triggered');
    currentUser = null;
    currentPrescriptions = [];
    document.getElementById('loginSection').querySelector('form')?.reset();
    document.getElementById('signupForm').reset();
    document.getElementById('prescribeForm').reset();
    document.getElementById('symptomsForm').reset();
    document.getElementById('orderForm').reset();
    document.getElementById('stockForm').reset();
    document.getElementById('prescriptions').innerHTML = '';
    document.getElementById('prescriptionPrice').innerHTML = '';
    document.getElementById('qrCode').innerHTML = '';
    document.getElementById('patientMedicalRecords').innerHTML = '';
    document.getElementById('analytics').innerHTML = '';
    document.getElementById('pendingOrders').innerHTML = '';
    document.getElementById('lowStock').innerHTML = '';
    document.getElementById('nearbyPharmacies').innerHTML = '';
    document.getElementById('refillReminders').innerHTML = '';
    document.getElementById('patientId').innerHTML = '<option value="" disabled selected>Select a Patient</option>';
    document.getElementById('medicineId').innerHTML = '<option value="" disabled selected>Select a Medicine</option>';
    document.getElementById('prescriptionId').innerHTML = '<option value="" disabled selected>Select a Prescription</option>';
    document.getElementById('pharmacyId').innerHTML = '<option value="" disabled selected>Select a Pharmacy</option>';
    document.getElementById('zipCode').innerHTML = '<option value="" disabled selected>Select Zip Code</option>';
    document.getElementById('medicineIdPharmacy').innerHTML = '<option value="" disabled selected>Select Medicine</option>';
    document.getElementById('medicineIdStock').innerHTML = '<option value="" disabled selected>Select a Medicine</option>';
    showLogin();
    showToast('Logged out successfully!', 'success');
    console.log('Login section displayed after logout');
}

function signup() {
    const signupButton = document.querySelector('#signupForm button[type="submit"]');
    setLoading(signupButton, true);

    const data = {
        role: document.getElementById('signupRole').value,
        username: document.getElementById('signupUsername').value,
        password: document.getElementById('signupPassword').value,
        name: document.getElementById('signupName').value,
        email: document.getElementById('signupEmail').value,
        zip_code: document.getElementById('signupZipCode').value,
        allergies: document.getElementById('signupAllergies').value,
        symptoms: document.getElementById('signupSymptoms').value
    };

    if (!data.role || !data.username || !data.password || !data.name) {
        showToast('Please fill in all required fields.', 'warning');
        setLoading(signupButton, false);
        return;
    }

    console.log('Signup request data:', JSON.stringify(data, null, 2));

    fetch('/signup', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(data)
    })
    .then(response => {
        console.log('Signup response status:', response.status);
        if (!response.ok) {
            return response.json().then(err => { throw new Error(err.message || `HTTP error! status: ${response.status}`); });
        }
        return response.json();
    })
    .then(data => {
        console.log('Signup response data:', JSON.stringify(data, null, 2));
        if (data.status === 'success') {
            showToast('Registration successful! Please login.', 'success');
            showLogin();
            document.getElementById('signupForm').reset();
        } else {
            showToast(data.message || 'Signup failed.', 'danger');
        }
    })
    .catch(error => {
        console.error('Signup error:', error);
        showToast(error.message || 'Error connecting to the server.', 'danger');
    })
    .finally(() => {
        setLoading(signupButton, false);
    });
}

function login() {
    const loginButton = document.getElementById('loginButton');
    setLoading(loginButton, true);

    const role = document.getElementById('loginRole').value;
    const username = document.getElementById('loginUsername').value;
    const password = document.getElementById('loginPassword').value;

    if (!role || !username || !password) {
        showToast('Please fill in all required fields.', 'warning');
        setLoading(loginButton, false);
        return;
    }

    const data = { username, password, role };
    console.log('Login request data:', JSON.stringify(data, null, 2));

    fetch('/login', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(data)
    })
    .then(response => {
        console.log('Login response status:', response.status, 'OK:', response.ok);
        if (!response.ok) {
            return response.json().then(err => {
                console.error('Login error response:', err);
                throw new Error(err.message || `HTTP error! status: ${response.status}`);
            });
        }
        return response.json();
    })
    .then(data => {
        console.log('Login response data:', JSON.stringify(data, null, 2));
        if (data.status === 'success') {
            currentUser = { id: data.user_id, role: data.role, name: data.name };
            hideDashboards();
            if (role === 'Doctor') {
                document.getElementById('doctorDashboard').classList.remove('d-none');
                document.getElementById('doctorName').textContent = data.name;
                fetchPatients();
                fetchMedicines();
            } else if (role === 'Patient') {
                document.getElementById('patientDashboard').classList.remove('d-none');
                document.getElementById('patientName').textContent = data.name;
                fetchPrescriptions();
                fetchPharmacies();
                fetchZipCodes();
                fetchMedicinesForPharmacy();
                fetchCurrentSymptoms();
                document.getElementById('orderForm').reset();
                updateButtonStates();
            } else if (role === 'Pharmacy') {
                document.getElementById('pharmacyDashboard').classList.remove('d-none');
                document.getElementById('pharmacyName').textContent = data.name;
                fetchMedicinesForStock();
            }
            showToast('Login successful!', 'success');
        } else {
            showToast(data.message || 'Invalid credentials.', 'danger');
        }
    })
    .catch(error => {
        console.error('Login fetch error:', error);
        showToast(error.message || 'Error connecting to the server.', 'danger');
    })
    .finally(() => {
        setLoading(loginButton, false);
        console.log('Login request completed');
    });
}

function updateSymptoms() {
    const symptomsButton = document.querySelector('#symptomsForm button[type="submit"]');
    setLoading(symptomsButton, true);

    const symptoms = document.getElementById('patientSymptoms').value;
    if (!symptoms) {
        showToast('Please enter symptoms.', 'warning');
        setLoading(symptomsButton, false);
        return;
    }

    const data = {
        patient_id: currentUser.id,
        symptoms: symptoms
    };

    fetch('/update_symptoms', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(data)
    })
    .then(response => response.json())
    .then(data => {
        if (data.status === 'success') {
            showToast('Symptoms updated successfully!', 'success');
            document.getElementById('symptomsForm').reset();
            fetchCurrentSymptoms();
        } else {
            showToast(data.message || 'Error updating symptoms.', 'danger');
        }
    })
    .catch(error => {
        console.error('Error updating symptoms:', error);
        showToast('Error connecting to server.', 'danger');
    })
    .finally(() => {
        setLoading(symptomsButton, false);
    });
}

function fetchCurrentSymptoms() {
    fetch(`/medical_records/${currentUser.id}`)
    .then(response => response.json())
    .then(data => {
        if (data.status === 'success') {
            document.getElementById('patientSymptoms').value = data.symptoms !== 'None' ? data.symptoms : '';
        }
    })
    .catch(error => console.error('Error fetching symptoms:', error));
}

function fetchPatientMedicalRecords() {
    const patientId = document.getElementById('patientId').value;
    if (!patientId) return;

    fetch(`/medical_records/${patientId}`)
    .then(response => response.json())
    .then(data => {
        const recordsDiv = document.getElementById('patientMedicalRecords');
        if (data.status === 'success') {
            recordsDiv.innerHTML = `
                <p><strong>Allergies:</strong> ${data.allergies}</p>
                <p><strong>Symptoms:</strong> ${data.symptoms}</p>
            `;
        } else {
            recordsDiv.innerHTML = '<p>No medical records found.</p>';
        }
    })
    .catch(error => {
        console.error('Error fetching medical records:', error);
        document.getElementById('patientMedicalRecords').innerHTML = '<p>Error loading records.</p>';
    });
}

function fetchPatients() {
    fetch('/patients')
    .then(response => response.json())
    .then(data => {
        const patientSelect = document.getElementById('patientId');
        patientSelect.innerHTML = '<option value="" disabled selected>Select a Patient</option>';
        if (data.length === 0) {
            patientSelect.innerHTML += '<option value="" disabled>No patients available</option>';
            return;
        }
        data.forEach(patient => {
            patientSelect.innerHTML += `<option value="${patient.id}">${patient.name} (ID: ${patient.id})</option>`;
        });
    })
    .catch(error => console.error('Error fetching patients:', error));
}

function fetchMedicines() {
    fetch('/medicines')
    .then(response => response.json())
    .then(data => {
        const medicineSelect = document.getElementById('medicineId');
        medicineSelect.innerHTML = '<option value="" disabled selected>Select a Medicine</option>';
        if (data.length === 0) {
            medicineSelect.innerHTML += '<option value="" disabled>No medicines available</option>';
            return;
        }
        data.forEach(medicine => {
            medicineSelect.innerHTML += `<option value="${medicine.id}">${medicine.name} ($${medicine.price.toFixed(2)})</option>`;
        });
    })
    .catch(error => console.error('Error fetching medicines:', error));
}

function fetchMedicinesForPharmacy() {
    fetch('/medicines')
    .then(response => response.json())
    .then(data => {
        const medicineSelect = document.getElementById('medicineIdPharmacy');
        medicineSelect.innerHTML = '<option value="" disabled selected>Select Medicine</option>';
        if (data.length === 0) {
            medicineSelect.innerHTML += '<option value="" disabled>No medicines available</option>';
            return;
        }
        data.forEach(medicine => {
            medicineSelect.innerHTML += `<option value="${medicine.id}">${medicine.name} ($${medicine.price.toFixed(2)})</option>`;
        });
    })
    .catch(error => console.error('Error fetching medicines for pharmacy:', error));
}

function fetchMedicinesForStock() {
    fetch('/medicines')
    .then(response => response.json())
    .then(data => {
        const medicineSelect = document.getElementById('medicineIdStock');
        medicineSelect.innerHTML = '<option value="" disabled selected>Select a Medicine</option>';
        medicineSelect.innerHTML += '<option value="new">Add New Tablet</option>';
        if (data.length === 0) {
            return;
        }
        data.forEach(medicine => {
            medicineSelect.innerHTML += `<option value="${medicine.id}">${medicine.name} ($${medicine.price.toFixed(2)})</option>`;
        });
    })
    .catch(error => console.error('Error fetching medicines for stock:', error));
}

function fetchPharmacies() {
    fetch('/pharmacies')
    .then(response => response.json())
    .then(data => {
        const pharmacySelect = document.getElementById('pharmacyId');
        pharmacySelect.innerHTML = '<option value="" disabled selected>Select a Pharmacy</option>';
        if (data.length === 0) {
            pharmacySelect.innerHTML += '<option value="" disabled>No pharmacies available</option>';
            return;
        }
        data.forEach(pharmacy => {
            pharmacySelect.innerHTML += `<option value="${pharmacy.id}">${pharmacy.name} (ID: ${pharmacy.id})</option>`;
        });
    })
    .catch(error => console.error('Error fetching pharmacies:', error));
}

function fetchZipCodes() {
    fetch('/zip_codes')
    .then(response => response.json())
    .then(data => {
        const zipSelect = document.getElementById('zipCode');
        zipSelect.innerHTML = '<option value="" disabled selected>Select Zip Code</option>';
        if (data.length === 0) {
            zipSelect.innerHTML += '<option value="" disabled>No zip codes available</option>';
            return;
        }
        data.forEach(zip => {
            zipSelect.innerHTML += `<option value="${zip}">${zip}</option>`;
        });
    })
    .catch(error => console.error('Error fetching zip codes:', error));
}

function prescribe() {
    const prescribeButton = document.querySelector('#prescribeForm button[type="submit"]');
    setLoading(prescribeButton, true);

    const data = {
        doctor_id: currentUser.id,
        patient_id: document.getElementById('patientId').value,
        medicine_id: document.getElementById('medicineId').value,
        symptoms: document.getElementById('symptoms').value,
        dosage: document.getElementById('dosage').value,
        duration: document.getElementById('duration').value
    };

    fetch('/prescribe', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(data)
    })
    .then(response => response.json())
    .then(data => {
        if (data.status === 'success') {
            showToast('Prescription created successfully', 'success');
            document.getElementById('prescribeForm').reset();
            document.getElementById('patientMedicalRecords').innerHTML = '';
            fetchPatients();
        } else {
            showToast(data.message || 'Error creating prescription', 'danger');
        }
    })
    .catch(error => {
        console.error('Error:', error);
        showToast('Error connecting to server', 'danger');
    })
    .finally(() => {
        setLoading(prescribeButton, false);
    });
}

function displayPrescriptionPrice() {
    const prescriptionId = document.getElementById('prescriptionId').value;
    const priceDiv = document.getElementById('prescriptionPrice');
    if (!prescriptionId) {
        priceDiv.innerHTML = '';
        return;
    }

    const prescription = currentPrescriptions.find(p => p.id === parseInt(prescriptionId));
    if (prescription) {
        priceDiv.innerHTML = `<p><strong>Price:</strong> $${prescription.price.toFixed(2)}</p>`;
    } else {
        priceDiv.innerHTML = '<p>Price not available.</p>';
    }
    updateButtonStates();
}

function updateButtonStates() {
    const prescriptionId = document.getElementById('prescriptionId').value;
    const pharmacyId = document.getElementById('pharmacyId').value;
    const paymentMethod = document.getElementById('paymentMethod').value;
    const upiApp = document.getElementById('upiApp').value;
    const orderId = document.getElementById('orderId').value;
    const placeOrderBtn = document.getElementById('placeOrderButton');
    const confirmButton = document.getElementById('confirmPayment');
    const upiForm = document.getElementById('upiForm');
    const upiSelect = document.getElementById('upiApp');

    console.log('Updating button states:', JSON.stringify({ prescriptionId, pharmacyId, paymentMethod, upiApp, orderId }, null, 2));

    placeOrderBtn.disabled = !(prescriptionId && pharmacyId && paymentMethod);

    if (paymentMethod === 'upi') {
        upiForm.classList.remove('d-none');
        upiSelect.disabled = false;
        confirmButton.disabled = !(orderId && upiApp);
        console.log('Confirm button state:', JSON.stringify({ orderId, upiApp, disabled: confirmButton.disabled }, null, 2));
    } else {
        upiForm.classList.add('d-none');
        upiSelect.disabled = true;
        upiSelect.value = '';
        confirmButton.disabled = true;
        document.getElementById('qrCode').innerHTML = '';
        console.log('UPI form hidden, confirm button disabled');
    }
}

function generateQRCode(orderId, amount) {
    const upiApp = document.getElementById('upiApp').value;
    if (!upiApp) {
        showToast('Please select a UPI app before generating QR code.', 'warning');
        return;
    }
    const pharmacyUpiId = 'pharmacy@upi';
    const pharmacyName = 'City Pharmacy';
    const upiUri = `upi://pay?pa=${encodeURIComponent(pharmacyUpiId)}&pn=${encodeURIComponent(pharmacyName)}&am=${encodeURIComponent(amount)}&cu=INR&tn=Order${orderId}`;

    console.log('Generated UPI URI:', upiUri);

    const qrCodeDiv = document.getElementById('qrCode');
    qrCodeDiv.innerHTML = '';
    if (typeof QRCode === 'undefined') {
        console.error('QRCode library not loaded');
        showToast('QR code generation failed: Library not loaded.', 'danger');
        return;
    }
    try {
        new QRCode(qrCodeDiv, {
            text: upiUri,
            width: 200,
            height: 200
        });
        console.log('QR code generated successfully for order:', orderId);
    } catch (error) {
        console.error('Error generating QR code:', error);
        showToast('Failed to generate QR code.', 'danger');
    }
}

function confirmPayment() {
    console.log('Confirm Payment button clicked');
    const orderId = document.getElementById('orderId').value;
    const paymentMethod = document.getElementById('paymentMethod').value;
    const upiApp = document.getElementById('upiApp').value;

    console.log('Confirm payment attempt:', JSON.stringify({ orderId, paymentMethod, upiApp }, null, 2));

    if (!orderId || !paymentMethod) {
        showToast('Order ID or payment method missing.', 'warning');
        console.log('Confirm payment validation failed:', { orderId, paymentMethod, upiApp });
        return;
    }

    if (paymentMethod === 'upi' && !upiApp) {
        showToast('Please select a UPI app.', 'warning');
        console.log('UPI app not selected:', { upiApp });
        return;
    }

    const data = { order_id: orderId, payment_method: paymentMethod };
    console.log('Confirm payment request data:', JSON.stringify(data, null, 2));

    fetch('/generate_payment', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(data)
    })
    .then(response => {
        console.log('Generate payment response status:', response.status, 'OK:', response.ok);
        if (!response.ok) {
            return response.json().then(err => {
                console.error('Generate payment error response:', err);
                throw new Error(err.message || `HTTP error! status: ${response.status}`);
            });
        }
        return response.json();
    })
    .then(data => {
        console.log('Generate payment response data:', JSON.stringify(data, null, 2));
        if (data.status === 'success') {
            showToast('Payment confirmed successfully!', 'success');
            document.getElementById('prescriptionId').value = '';
            document.getElementById('pharmacyId').value = '';
            document.getElementById('paymentMethod').value = '';
            document.getElementById('upiApp').value = '';
            document.getElementById('orderId').value = '';
            document.getElementById('qrCode').innerHTML = '';
            document.getElementById('placeOrderButton').disabled = true;
            document.getElementById('upiForm').classList.add('d-none');
            document.getElementById('confirmPayment').disabled = true;
            fetchPrescriptions();
        } else {
            showToast(data.message || 'Error confirming payment.', 'danger');
            console.log('Payment confirmation failed:', data);
        }
    })
    .catch(error => {
        console.error('Confirm payment fetch error:', error);
        showToast(error.message || 'Error connecting to server.', 'danger');
    });
}

function fetchPrescriptions() {
    fetch(`/prescriptions/${currentUser.id}`)
    .then(response => response.json())
    .then(data => {
        currentPrescriptions = data;
        const prescriptionsDiv = document.getElementById('prescriptions');
        prescriptionsDiv.innerHTML = '<h4 class="h4 fw-semibold">Prescriptions</h4>';
        if (data.length === 0) {
            prescriptionsDiv.innerHTML += '<p>No prescriptions found.</p>';
        } else {
            data.forEach(p => {
                prescriptionsDiv.innerHTML += `
                    <div class="border p-3 mb-2 rounded bg-light">
                        <p><strong>Prescription ID:</strong> ${p.id}</p>
                        <p><strong>Medicine:</strong> ${p.medicine}</p>
                        <p><strong>Price:</strong> $${p.price.toFixed(2)}</p>
                        <p><strong>Symptoms:</strong> ${p.symptoms || 'N/A'}</p>
                        <p><strong>Dosage:</strong> ${p.dosage}</p>
                        <p><strong>Duration:</strong> ${p.duration} days</p>
                        <p><strong>Date:</strong> ${p.date}</p>
                        <p><strong>Side Effects:</strong> ${p.side_effects || 'None'}</p>
                    </div>
                `;
            });
        }

        const prescriptionSelect = document.getElementById('prescriptionId');
        prescriptionSelect.innerHTML = '<option value="" disabled selected>Select a Prescription</option>';
        if (data.length === 0) {
            prescriptionSelect.innerHTML += '<option value="" disabled>No prescriptions available</option>';
        } else {
            data.forEach(p => {
                prescriptionSelect.innerHTML += `<option value="${p.id}">${p.medicine} ($${p.price.toFixed(2)}, Date: ${p.date})</option>`;
            });
        }
        displayPrescriptionPrice();
        updateButtonStates();
    })
    .catch(error => console.error('Error fetching prescriptions:', error));
}

function placeOrder() {
    const orderButton = document.querySelector('#placeOrderButton');
    setLoading(orderButton, true);

    const prescriptionId = document.getElementById('prescriptionId').value;
    const pharmacyId = document.getElementById('pharmacyId').value;
    const paymentMethod = document.getElementById('paymentMethod').value;
    const upiApp = document.getElementById('upiApp').value;

    if (!prescriptionId || !pharmacyId || !paymentMethod) {
        showToast('Please fill in all required fields.', 'warning');
        setLoading(orderButton, false);
        return;
    }

    const data = {
        prescription_id: prescriptionId,
        pharmacy_id: pharmacyId,
        patient_id: currentUser.id
    };

    console.log('Place order request data:', JSON.stringify(data, null, 2));

    fetch('/order', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(data)
    })
    .then(response => {
        console.log('Place order response status:', response.status, 'OK:', response.ok);
        if (!response.ok) {
            return response.json().then(err => {
                console.error('Place order error response:', err);
                throw new Error(err.message || `HTTP error! status: ${response.status}`);
            });
        }
        return response.json();
    })
    .then(data => {
        console.log('Place order response data:', JSON.stringify(data, null, 2));
        if (data.status === 'success') {
            showToast('Order placed successfully', 'success');
            if (!data.order_id) {
                console.error('Order ID not returned from server');
                showToast('Error: Order ID not received.', 'danger');
                setLoading(orderButton, false);
                return;
            }
            document.getElementById('orderId').value = data.order_id;
            console.log('Order ID set to:', data.order_id);
            if (paymentMethod === 'upi') {
                if (upiApp) {
                    generateQRCode(data.order_id, data.price);
                } else {
                    showToast('Please select a UPI app to proceed with payment.', 'warning');
                }
                updateButtonStates();
            } else {
                confirmPayment();
            }
        } else {
            if (data.alternatives) {
                showToast(`Out of stock. Try these pharmacies: ${data.alternatives.map(a => a.name).join(', ')}`, 'warning');
            } else {
                showToast(data.message || 'Error placing order', 'danger');
            }
        }
    })
    .catch(error => {
        console.error('Place order fetch error:', error);
        showToast(error.message || 'Error connecting to server', 'danger');
    })
    .finally(() => {
        setLoading(orderButton, false);
    });
}

function fetchOrders() {
    fetch(`/orders/${currentUser.id}`)
    .then(response => response.json())
    .then(data => {
        const ordersDiv = document.getElementById('pendingOrders');
        ordersDiv.innerHTML = '<h4 class="h4 fw-semibold">Orders</h4>';
        if (data.length === 0) {
            ordersDiv.innerHTML += '<p>No orders found.</p>';
            return;
        }
        data.forEach(o => {
            ordersDiv.innerHTML += `
                <div class="border p-3 mb-2 rounded bg-light">
                    <p><strong>Order ID:</strong> ${o.order_id}</p>
                    <p><strong>Prescription ID:</strong> ${o.prescription_id}</p>
                    <p><strong>Medicine:</strong> ${o.medicine}</p>
                    <p><strong>Price:</strong> $${o.price.toFixed(2)}</p>
                    <p><strong>Status:</strong> ${o.status}</p>
                    <button class="btn btn-success btn-sm me-2" data-order-id="${o.order_id}" data-status="Fulfilled">Mark Fulfilled</button>
                    <button class="btn btn-danger btn-sm" data-order-id="${o.order_id}" data-status="Cancelled">Cancel</button>
                </div>
            `;
        });

        document.querySelectorAll('#pendingOrders button').forEach(button => {
            button.addEventListener('click', (e) => {
                const orderId = e.target.getAttribute('data-order-id');
                const status = e.target.getAttribute('data-status');
                updateOrderStatus(orderId, status);
            });
        });
    })
    .catch(error => console.error('Error:', error));
}

function updateOrderStatus(orderId, status) {
    fetch('/update_order', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ order_id: orderId, status })
    })
    .then(response => response.json())
    .then(data => {
        if (data.status === 'success') {
            showToast(`Order ${status} successfully`, 'success');
            fetchOrders();
        } else {
            showToast('Error updating order', 'danger');
        }
    })
    .catch(error => {
        console.error('Error:', error);
        showToast('Error connecting to server', 'danger');
    });
}

function fetchMostPrescribed() {
    fetch('/most_prescribed')
    .then(response => response.json())
    .then(data => {
        const analyticsDiv = document.getElementById('analytics');
        analyticsDiv.innerHTML = '<h4 class="h4 fw-semibold">Most Prescribed Medicines</h4>';
        if (data.length === 0) {
            analyticsDiv.innerHTML += '<p>No data available.</p>';
            return;
        }
        data.forEach(d => {
            analyticsDiv.innerHTML += `<p>${d.medicine}: ${d.count} prescriptions</p>`;
        });
    })
    .catch(error => console.error('Error:', error));
}

function fetchLowStock() {
    fetch(`/low_stock/${currentUser.id}`)
    .then(response => response.json())
    .then(data => {
        const lowStockDiv = document.getElementById('lowStock');
        lowStockDiv.innerHTML = '<h4 class="h4 fw-semibold">Low Stock Alerts</h4>';
        if (data.length === 0) {
            lowStockDiv.innerHTML += '<p>No low stock items.</p>';
            return;
        }
        data.forEach(d => {
            lowStockDiv.innerHTML += `<p>${d.medicine}: ${d.quantity} units</p>`;
        });
    })
    .catch(error => console.error('Error:', error));
}

function findPharmacies() {
    const findButton = document.getElementById('findPharmaciesButton');
    setLoading(findButton, true);

    const zipCode = document.getElementById('zipCode').value;
    const medicineId = document.getElementById('medicineIdPharmacy').value;
    if (!zipCode || !medicineId) {
        showToast('Please select both a zip code and a medicine.', 'warning');
        setLoading(findButton, false);
        return;
    }
    fetch(`/nearby_pharmacies/${zipCode}/${medicineId}`)
    .then(response => response.json())
    .then(data => {
        const pharmaciesDiv = document.getElementById('nearbyPharmacies');
        pharmaciesDiv.innerHTML = '<h4 class="h4 fw-semibold">Nearby Pharmacies</h4>';
        if (data.length === 0) {
            pharmaciesDiv.innerHTML += '<p>No pharmacies found with stock.</p>';
            return;
        }
        data.forEach(p => {
            pharmaciesDiv.innerHTML += `<p>ID: ${p.id}, Name: ${p.name}</p>`;
        });
    })
    .catch(error => {
        console.error('Error:', error);
        showToast('Error connecting to server', 'danger');
    })
    .finally(() => {
        setLoading(findButton, false);
    });
}

function fetchRefillReminders() {
    fetch(`/refill_reminders/${currentUser.id}`)
    .then(response => response.json())
    .then(data => {
        const remindersDiv = document.getElementById('refillReminders');
        remindersDiv.innerHTML = '<h4 class="h4 fw-semibold">Refill Reminders</h4>';
        if (data.length === 0) {
            remindersDiv.innerHTML += '<p>No refills due.</p>';
            return;
        }
        data.forEach(r => {
            remindersDiv.innerHTML += `<p>Prescription ID: ${r.prescription_id}, Medicine: ${r.medicine}</p>`;
        });
    })
    .catch(error => console.error('Error:', error));
}

function toggleNewTabletFields() {
    const medicineSelect = document.getElementById('medicineIdStock');
    const newTabletFields = document.getElementById('newTabletFields');
    const inputs = [
        document.getElementById('newTabletName'),
        document.getElementById('newTabletStrength'),
        document.getElementById('newTabletManufacturer'),
        document.getElementById('newTabletPrice')
    ];
    if (medicineSelect.value === 'new') {
        newTabletFields.classList.remove('d-none');
        inputs.forEach(input => input.disabled = false);
    } else {
        newTabletFields.classList.add('d-none');
        inputs.forEach(input => {
            input.disabled = true;
            input.value = '';
        });
    }
}

function updateStock() {
    const stockButton = document.querySelector('#stockForm button[type="submit"]');
    setLoading(stockButton, true);

    const medicineId = document.getElementById('medicineIdStock').value;
    const quantity = document.getElementById('quantity').value;
    const data = {
        pharmacy_id: currentUser.id,
        medicine_id: medicineId,
        quantity: parseInt(quantity)
    };

    if (medicineId === 'new') {
        data.new_tablet = {
            name: document.getElementById('newTabletName').value,
            strength: document.getElementById('newTabletStrength').value,
            manufacturer: document.getElementById('newTabletManufacturer').value,
            price: parseFloat(document.getElementById('newTabletPrice').value) || 0.0
        };
    }

    if (!quantity || (medicineId === 'new' && (!data.new_tablet.name || !data.new_tablet.strength || !data.new_tablet.manufacturer))) {
        showToast('Please fill in all required fields.', 'warning');
        setLoading(stockButton, false);
        return;
    }

    fetch('/update_stock', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(data)
    })
    .then(response => response.json())
    .then(data => {
        if (data.status === 'success') {
            showToast('Stock updated successfully', 'success');
            document.getElementById('stockForm').reset();
            toggleNewTabletFields();
            fetchMedicinesForStock();
        } else {
            showToast(data.message || 'Error updating stock', 'danger');
        }
    })
    .catch(error => {
        console.error('Error:', error);
        showToast('Error connecting to server', 'danger');
    })
    .finally(() => {
        setLoading(stockButton, false);
    });
}

function setLoading(button, isLoading) {
    if (isLoading) {
        button.disabled = true;
        button.innerHTML = '<span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span> Loading...';
    } else {
        button.disabled = false;
        button.innerHTML = button.id === 'loginButton' ? 'Login' : 
                          button.id === 'placeOrderButton' ? 'Place Order' : 
                          button.id === 'findPharmaciesButton' ? 'Find Pharmacies' : 
                          button.id === 'checkLowStockButton' ? 'Check Low Stock' : 
                          'Submit';
    }
}

function showToast(message, type) {
    const toastContainer = document.createElement('div');
    toastContainer.className = `toast align-items-center text-white bg-${type} border-0 position-fixed bottom-0 end-0 m-3`;
    toastContainer.setAttribute('role', 'alert');
    toastContainer.setAttribute('aria-live', 'assertive');
    toastContainer.setAttribute('aria-atomic', 'true');
    toastContainer.innerHTML = `
        <div class="d-flex">
            <div class="toast-body">${message}</div>
            <button type="button" class="btn-close btn-close-white me-2 m-auto" data-bs-dismiss="toast" aria-label="Close"></button>
        </div>
    `;
    document.body.appendChild(toastContainer);
    const toast = new bootstrap.Toast(toastContainer);
    toast.show();
    setTimeout(() => toastContainer.remove(), 3000);
}