import type { Plan } from "@/lib/api";
import { limitLabel } from "@/lib/format";
import { Button } from "./Button";

/*
 * Editing a plan changes what every future customer gets, so the confirmation
 * names each field rather than asking "are you sure". Existing licences
 * snapshotted their plan at issue time and are genuinely unaffected — saying so
 * is what stops a well-meaning edit being followed by a panicked reissue.
 */
export function ConfirmPlanChange({
    plan,
    next,
    issuedCount,
    onConfirm,
    onCancel,
}: {
    plan: Plan;
    next: Plan;
    issuedCount: number;
    onConfirm: () => void;
    onCancel: () => void;
}) {
    const rows: { field: string; was: string; now: string }[] = [];
    const fields = [
        "max_servers",
        "max_monitors",
        "max_secret_groups",
        "max_channels",
        "audit_retention_days",
    ] as const;
    for (const f of fields) {
        if (plan.base_limits[f] !== next.base_limits[f])
            rows.push({
                field: f,
                was: limitLabel(plan.base_limits[f]),
                now: limitLabel(next.base_limits[f]),
            });
    }
    if (plan.support_level !== next.support_level)
        rows.push({
            field: "support_level",
            was: plan.support_level || "none",
            now: next.support_level || "none",
        });
    if (plan.base_features.join(",") !== next.base_features.join(","))
        rows.push({
            field: "features",
            was: plan.base_features.join(", ") || "none",
            now: next.base_features.join(", ") || "none",
        });

    return (
        <div className="grid max-w-xl gap-3 rounded border border-warn bg-panel p-5">
            <h2 className="text-xl">Change what {plan.name} grants?</h2>
            <ul className="grid gap-1 font-mono text-[0.82rem]">
                {rows.map((r) => (
                    <li key={r.field} className="flex flex-wrap gap-2">
                        <span className="text-ink-3">{r.field}</span>
                        <span className="text-ink-3 line-through">{r.was}</span>
                        <span className="font-semibold text-ink">→ {r.now}</span>
                    </li>
                ))}
                {rows.length === 0 && <li className="text-ink-3">Nothing would change.</li>}
            </ul>
            <p className="text-[0.82rem] text-ink-3">
                This applies to licences issued from now on. The {issuedCount} licences already
                issued keep what they were signed with until each is reissued.
            </p>
            <div className="flex flex-wrap gap-3">
                <Button type="button" onClick={onConfirm}>
                    Change plan
                </Button>
                <Button type="button" variant="line" onClick={onCancel}>
                    Keep as is
                </Button>
            </div>
        </div>
    );
}