import { useState, useEffect } from 'react';
import { FontAwesomeIcon } from '@fortawesome/react-fontawesome';
import { faUserPen } from '@fortawesome/pro-duotone-svg-icons';
import { Input } from '@/components/base/input/input';
import { Select } from '@/components/base/select/select';
import { TextArea } from '@/components/base/textarea/textarea';
import { Checkbox } from '@/components/base/checkbox/checkbox';
import { Button } from '@/components/base/buttons/button';
import { EditPatientConfirmModal } from '@/components/modals/edit-patient-confirm-modal';
import { apiClient } from '@/lib/api-client';
import { notify } from '@/lib/toast';

type EnquiryFormProps = {
    isOpen: boolean;
    onOpenChange: (open: boolean) => void;
    callerPhone?: string | null;
    // Pre-populated caller name (from caller-resolution). When set, the
    // patient-name field is locked behind the Edit-confirm modal to
    // prevent accidental rename-on-save. When empty or null, the field
    // starts unlocked because there's no existing name to protect.
    leadName?: string | null;
    leadId?: string | null;
    patientId?: string | null;
    agentName?: string | null;
    onSaved?: () => void;
};


export const EnquiryForm = ({ isOpen, onOpenChange, callerPhone, leadName, leadId: propLeadId, patientId, agentName, onSaved }: EnquiryFormProps) => {
    // Initial name captured at form open — used to detect whether the
    // agent actually changed the name before committing any updatePatient /
    // updateLead.contactName mutations. See also appointment-form.tsx.
    const initialLeadName = (leadName ?? '').trim();
    const [patientName, setPatientName] = useState(leadName ?? '');
    const [isNameEditable, setIsNameEditable] = useState(initialLeadName.length === 0);
    const [editConfirmOpen, setEditConfirmOpen] = useState(false);
    const [source, setSource] = useState('Phone Inquiry');
    const [queryAsked, setQueryAsked] = useState('');
    const [isExisting, setIsExisting] = useState(false);
    const [registeredPhone, setRegisteredPhone] = useState(callerPhone ?? '');
    const [department, setDepartment] = useState<string | null>(null);
    const [doctor, setDoctor] = useState<string | null>(null);
    const [followUpNeeded, setFollowUpNeeded] = useState(false);
    const [followUpDate, setFollowUpDate] = useState('');
    const [isSaving, setIsSaving] = useState(false);
    const [error, setError] = useState<string | null>(null);

    // Fetch doctors for department/doctor dropdowns
    const [doctors, setDoctors] = useState<Array<{ id: string; name: string; department: string }>>([]);

    useEffect(() => {
        if (!isOpen) return;
        apiClient.graphql<{ doctors: { edges: Array<{ node: any }> } }>(
            `{ doctors(first: 50) { edges { node {
                id name fullName { firstName lastName } department
            } } } }`,
        ).then(data => {
            setDoctors(data.doctors.edges.map(e => ({
                id: e.node.id,
                name: e.node.fullName ? `Dr. ${e.node.fullName.firstName} ${e.node.fullName.lastName}`.trim() : e.node.name,
                department: e.node.department ?? '',
            })));
        }).catch(() => {});
    }, [isOpen]);

    const departmentItems = [...new Set(doctors.map(d => d.department).filter(Boolean))]
        .map(dept => ({ id: dept, label: dept.replace(/_/g, ' ').replace(/\b\w/g, c => c.toUpperCase()) }));

    const filteredDoctors = department ? doctors.filter(d => d.department === department) : doctors;
    const doctorItems = filteredDoctors.map(d => ({ id: d.id, label: d.name }));

    const handleSave = async () => {
        if (!patientName.trim() || !queryAsked.trim()) {
            setError('Please fill in required fields: patient name and query.');
            return;
        }

        setIsSaving(true);
        setError(null);

        try {
            // Use passed leadId or resolve from phone
            let leadId: string | null = propLeadId ?? null;
            if (!leadId && registeredPhone) {
                const resolved = await apiClient.post<{ leadId: string; patientId: string }>('/api/caller/resolve', { phone: registeredPhone }, { silent: true });
                leadId = resolved.leadId;
            }

            // Determine whether the agent actually renamed the patient.
            // Only a non-empty, changed-from-initial name counts — empty
            // strings or an unchanged name never trigger the rename
            // chain, even if the field was unlocked.
            const trimmedName = patientName.trim();
            const nameChanged = isNameEditable && trimmedName.length > 0 && trimmedName !== initialLeadName;
            const nameParts = {
                firstName: trimmedName.split(' ')[0],
                lastName: trimmedName.split(' ').slice(1).join(' ') || '',
            };

            if (leadId) {
                // Update existing lead with enquiry details. Only touches
                // contactName if the agent explicitly renamed — otherwise
                // we leave the existing caller identity alone.
                await apiClient.graphql(
                    `mutation($id: UUID!, $data: LeadUpdateInput!) { updateLead(id: $id, data: $data) { id } }`,
                    {
                        id: leadId,
                        data: {
                            name: `Enquiry — ${trimmedName || 'Unknown caller'}`,
                            source: 'PHONE',
                            status: 'CONTACTED',
                            interestedService: queryAsked.substring(0, 100),
                            ...(nameChanged ? { contactName: nameParts } : {}),
                        },
                    },
                );
            } else {
                // No matched lead — create a fresh one. For net-new leads
                // we always populate contactName from the typed value
                // (there's no existing record to protect).
                await apiClient.graphql(
                    `mutation($data: LeadCreateInput!) { createLead(data: $data) { id } }`,
                    {
                        data: {
                            name: `Enquiry — ${trimmedName || 'Unknown caller'}`,
                            contactName: nameParts,
                            contactPhone: registeredPhone ? { primaryPhoneNumber: registeredPhone } : undefined,
                            source: 'PHONE',
                            status: 'CONTACTED',
                            interestedService: queryAsked.substring(0, 100),
                        },
                    },
                );
            }

            // Update linked patient's name ONLY if the agent explicitly
            // renamed. Fixes the long-standing bug where typing a name
            // into this form silently overwrote the existing patient
            // record.
            if (nameChanged && patientId) {
                await apiClient.graphql(
                    `mutation($id: UUID!, $data: PatientUpdateInput!) { updatePatient(id: $id, data: $data) { id } }`,
                    {
                        id: patientId,
                        data: {
                            fullName: nameParts,
                        },
                    },
                ).catch((err: unknown) => console.warn('Failed to update patient name:', err));
            }

            // Post-save side-effects. If the agent actually renamed the
            // patient, kick off AI summary regen + cache invalidation.
            // Otherwise just invalidate the cache so the status update
            // propagates.
            if (nameChanged && leadId) {
                apiClient.post(`/api/lead/${leadId}/enrich`, { phone: callerPhone ?? undefined }, { silent: true }).catch(() => {});
            } else if (callerPhone) {
                apiClient.post('/api/caller/invalidate', { phone: callerPhone }, { silent: true }).catch(() => {});
            }

            // Create follow-up if needed
            if (followUpNeeded) {
                if (!followUpDate) {
                    setError('Please select a follow-up date.');
                    setIsSaving(false);
                    return;
                }
                await apiClient.graphql(
                    `mutation($data: FollowUpCreateInput!) { createFollowUp(data: $data) { id } }`,
                    {
                        data: {
                            name: `Follow-up — ${patientName}`,
                            typeCustom: 'CALLBACK',
                            status: 'PENDING',
                            priority: 'NORMAL',
                            assignedAgent: agentName ?? undefined,
                            scheduledAt: new Date(`${followUpDate}T09:00:00`).toISOString(),
                            patientId: patientId ?? undefined,
                        },
                    },
                    { silent: true },
                );
            }

            notify.success('Enquiry Logged', 'Contact details and query captured');
            onSaved?.();
        } catch (err) {
            setError(err instanceof Error ? err.message : 'Failed to save enquiry');
        } finally {
            setIsSaving(false);
        }
    };

    if (!isOpen) return null;

    return (
        <div className="flex flex-col flex-1 min-h-0">
            {/* Form fields — scrollable */}
            <div className="flex-1 overflow-y-auto">
            <div className="flex flex-col gap-3">
                {/* Patient name — locked by default for existing callers,
                    unlocked for new callers with no prior name on record.
                    The Edit button opens a confirm modal before unlocking;
                    see EditPatientConfirmModal for the rationale. */}
                <div className="flex items-end gap-2">
                    <div className="flex-1">
                        <Input
                            label="Patient Name"
                            placeholder="Full name"
                            value={patientName}
                            onChange={setPatientName}
                            isRequired
                            isDisabled={!isNameEditable}
                        />
                    </div>
                    {!isNameEditable && initialLeadName.length > 0 && (
                        <Button
                            size="sm"
                            color="secondary"
                            iconLeading={({ className }: { className?: string }) => (
                                <FontAwesomeIcon icon={faUserPen} className={className} />
                            )}
                            onClick={() => setEditConfirmOpen(true)}
                        >
                            Edit
                        </Button>
                    )}
                </div>

                <Input label="Source / Referral" placeholder="How did they reach us?" value={source} onChange={setSource} isRequired />

                <TextArea label="Query Asked" placeholder="What did the caller ask about?" value={queryAsked} onChange={setQueryAsked} rows={3} isRequired />

                <Checkbox isSelected={isExisting} onChange={setIsExisting} label="Existing Patient" hint="Has visited the hospital before" />

                {isExisting && (
                    <Input label="Registered Phone" placeholder="Phone number on file" value={registeredPhone} onChange={setRegisteredPhone} />
                )}

                <div className="border-t border-secondary" />

                <div className="grid grid-cols-2 gap-3">
                    <Select label="Department" placeholder="Optional" items={departmentItems} selectedKey={department}
                        onSelectionChange={(key) => { setDepartment(key as string); setDoctor(null); }}>
                        {(item) => <Select.Item id={item.id} label={item.label} />}
                    </Select>
                    <Select label="Doctor" placeholder="Optional" items={doctorItems} selectedKey={doctor}
                        onSelectionChange={(key) => setDoctor(key as string)} isDisabled={!department}>
                        {(item) => <Select.Item id={item.id} label={item.label} />}
                    </Select>
                </div>

                <Checkbox isSelected={followUpNeeded} onChange={setFollowUpNeeded} label="Follow-up Needed" />

                {followUpNeeded && (
                    <Input label="Follow-up Date" type="date" value={followUpDate} onChange={setFollowUpDate} isRequired />
                )}

                {error && (
                    <div className="rounded-lg bg-error-primary p-3 text-sm text-error-primary">{error}</div>
                )}
            </div>
            </div>

            {/* Footer — pinned */}
            <div className="shrink-0 flex items-center justify-end gap-3 pt-4 border-t border-secondary">
                <Button size="sm" color="secondary" onClick={() => onOpenChange(false)}>Cancel</Button>
                <Button size="sm" color="primary" isLoading={isSaving} showTextWhileLoading onClick={handleSave}>
                    {isSaving ? 'Saving...' : 'Log Enquiry'}
                </Button>
            </div>

            <EditPatientConfirmModal
                isOpen={editConfirmOpen}
                onOpenChange={setEditConfirmOpen}
                onConfirm={() => {
                    setIsNameEditable(true);
                    setEditConfirmOpen(false);
                }}
                description={
                    <>
                        You&apos;re about to change the name on this patient&apos;s record. This will
                        update their profile across Helix Engage, including past appointments,
                        lead history, and AI summary. Only proceed if the current name is
                        actually wrong — for all other cases, cancel and continue logging the
                        enquiry as-is.
                    </>
                }
            />
        </div>
    );
};
