import { useEffect, useState } from 'react';
import { FontAwesomeIcon } from '@fortawesome/react-fontawesome';
import { faPhone, faRotateLeft } from '@fortawesome/pro-duotone-svg-icons';
import { Button } from '@/components/base/buttons/button';
import { TopBar } from '@/components/layout/top-bar';
import {
    TelephonyForm,
    emptyTelephonyFormValues,
    type TelephonyFormValues,
} from '@/components/forms/telephony-form';
import { apiClient } from '@/lib/api-client';
import { notify } from '@/lib/toast';
import { markSetupStepComplete } from '@/lib/setup-state';

// /settings/telephony — Pattern B page against the sidecar's
// /api/config/telephony endpoint. The sidecar masks secrets on GET (agent
// password + Exotel API token become '***masked***') and treats that sentinel
// as "no change" on PUT, so we just round-trip the form values directly.
//
// Changes take effect immediately — TelephonyConfigService keeps an in-memory
// cache that all consumers read via getters, no restart required.

export const TelephonySettingsPage = () => {
    const [values, setValues] = useState<TelephonyFormValues>(emptyTelephonyFormValues);
    const [loading, setLoading] = useState(true);
    const [isSaving, setIsSaving] = useState(false);
    const [isResetting, setIsResetting] = useState(false);

    const loadConfig = async () => {
        try {
            const data = await apiClient.get<TelephonyFormValues>('/api/config/telephony');
            setValues({
                ozonetel: {
                    agentId: data.ozonetel?.agentId ?? '',
                    agentPassword: data.ozonetel?.agentPassword ?? '',
                    did: data.ozonetel?.did ?? '',
                    sipId: data.ozonetel?.sipId ?? '',
                    campaignName: data.ozonetel?.campaignName ?? '',
                },
                sip: {
                    domain: data.sip?.domain ?? 'blr-pub-rtc4.ozonetel.com',
                    wsPort: data.sip?.wsPort ?? '444',
                },
                exotel: {
                    apiKey: data.exotel?.apiKey ?? '',
                    apiToken: data.exotel?.apiToken ?? '',
                    accountSid: data.exotel?.accountSid ?? '',
                    subdomain: data.exotel?.subdomain ?? 'api.exotel.com',
                },
            });
        } catch {
            // toast already shown
        } finally {
            setLoading(false);
        }
    };

    useEffect(() => {
        loadConfig();
    }, []);

    const handleSave = async () => {
        setIsSaving(true);
        try {
            await apiClient.put('/api/config/telephony', {
                ozonetel: values.ozonetel,
                sip: values.sip,
                exotel: values.exotel,
            });
            notify.success('Telephony updated', 'Changes are live — no restart needed.');
            // Mark the wizard step complete if the required Ozonetel fields are
            // all filled in. Keeps the setup hub badges in sync with reality.
            const complete =
                !!values.ozonetel.agentId &&
                !!values.ozonetel.did &&
                !!values.ozonetel.sipId &&
                !!values.ozonetel.campaignName;
            if (complete) {
                markSetupStepComplete('telephony').catch(() => {});
            }
            await loadConfig();
        } catch (err) {
            console.error('[telephony] save failed', err);
        } finally {
            setIsSaving(false);
        }
    };

    const handleReset = async () => {
        if (!confirm('Reset telephony settings to defaults? Your Ozonetel and Exotel credentials will be cleared.')) {
            return;
        }
        setIsResetting(true);
        try {
            await apiClient.post('/api/config/telephony/reset');
            notify.info('Telephony reset', 'All fields have been cleared.');
            await loadConfig();
        } catch (err) {
            console.error('[telephony] reset failed', err);
        } finally {
            setIsResetting(false);
        }
    };

    return (
        <div className="flex flex-1 flex-col overflow-hidden">
            <TopBar title="Telephony" subtitle="Connect Ozonetel and Exotel for calls and SMS" />

            <div className="flex-1 overflow-y-auto p-6">
                <div className="mx-auto max-w-2xl">
                    <div className="mb-6 flex items-center gap-3 rounded-lg border border-secondary bg-primary p-4">
                        <div className="flex size-10 items-center justify-center rounded-lg bg-brand-secondary">
                            <FontAwesomeIcon icon={faPhone} className="size-5 text-fg-brand-primary" />
                        </div>
                        <div className="flex-1">
                            <p className="text-sm font-semibold text-primary">Credentials are stored locally</p>
                            <p className="text-xs text-tertiary">
                                Values are written to the sidecar's data/telephony.json. API tokens are masked
                                when loaded — leave the <code className="rounded bg-secondary px-1 py-0.5 font-mono">***masked***</code>{' '}
                                placeholder to keep the existing value.
                            </p>
                        </div>
                    </div>

                    {loading ? (
                        <div className="flex items-center justify-center py-16">
                            <p className="text-sm text-tertiary">Loading telephony settings...</p>
                        </div>
                    ) : (
                        <div className="rounded-xl border border-secondary bg-primary p-6 shadow-xs">
                            <TelephonyForm value={values} onChange={setValues} />

                            <div className="mt-8 flex items-center justify-between border-t border-secondary pt-4">
                                <Button
                                    size="md"
                                    color="secondary"
                                    iconLeading={({ className }: { className?: string }) => (
                                        <FontAwesomeIcon icon={faRotateLeft} className={className} />
                                    )}
                                    onClick={handleReset}
                                    isLoading={isResetting}
                                    showTextWhileLoading
                                >
                                    Reset to defaults
                                </Button>
                                <Button
                                    size="md"
                                    color="primary"
                                    onClick={handleSave}
                                    isLoading={isSaving}
                                    showTextWhileLoading
                                >
                                    {isSaving ? 'Saving...' : 'Save changes'}
                                </Button>
                            </div>
                        </div>
                    )}
                </div>
            </div>
        </div>
    );
};
