// - reading the readiness facts off FHIR. The half that has to be right for the sentence above
// it to mean anything.
//
// EVERY FACT HERE HAS A SAFE DIRECTION AND THEY ARE NOT ALL THE SAME. Reporting a working person as
// broken sends an administrator on a wasted trip; reporting a broken person as working leaves a
// practitioner invisible to booking behind a page that says they are fine. The second is the failure
// this card exists to end, so where a fact cannot be established the answer is not "fine".
//
// IT DERIVES NO BOOKING VERDICT. That comes from `utils/booking/resolveBookability.ts` via
// `getProviderReadiness`, and is handed in - see `staffReadiness.ts`'s header for what the second
// implementation of that question already cost this codebase.
import type { Practitioner, PractitionerRole } from 'fhir/r4';
import type { BookabilityBlocker } from '../booking/bookabilityReasons';
import { isValidNpi } from '../npi';
import { holdsClinicalRole } from '../staffRoleCatalog';
import type { StaffFacts } from './staffReadiness';

const NPI_SYSTEM = 'http://hl7.org/fhir/sid/us-npi';

// **I GOT THIS WRONG ONCE AND THE CORRECTION IS WORTH MORE THAN THE CODE.** I read absence off
// `PractitionerRole.notAvailable`, reasoning that FHIR R4 has no such field on `Schedule`. True of the
// SPEC, wrong about this PRODUCT: the schedule carries its not-available periods in an Akashic
// extension (`SCHEDULE_NOT_AVAILABLE_EXTENSION_URL`), there are already two editors for them - Manage
// Schedule and Edit Availability - and `getScheduleAvailabilityEvents` already skips any day they
// cover, so booking honours them today.
// **Spencer's ruling was exact and I checked the spec instead of the codebase.** A field's absence
// from a standard says nothing about whether the product models it.
//
// SO `onLeave` IS HANDED IN, not derived here. It belongs to the SCHEDULE reader, and deriving it a
// second time from a resource nothing writes is the drift this module already warns about one field up.
interface Input {
    practitioner: Practitioner;
    roles: PractitionerRole[];
    /** From `getProviderReadiness`. NEVER re-derived here. */
    booking: { staffBookable: boolean; blockers: readonly BookabilityBlocker[]; basis?: 'confirmed' | 'checking' | 'unavailable' };
    // `now` LIVED HERE and is gone: this module stopped deriving absence, and it was the only fact
    // that needed a clock. A required parameter nothing reads is one every caller has to invent.
    /** Whether the invitation has been accepted, where the caller knows. See the default below. */
    inviteAccepted?: boolean;
    /**
 * Is this person AWAY today? Read off their SCHEDULES' not-available periods by the caller -
 * `getScheduleAvailability(schedule).notAvailable` is where the product stores them, and the two
 * existing editors are Manage Schedule and Edit Availability.
 * NOT derived here from `PractitionerRole.notAvailable`: nothing in the product writes that, and
 * a second derivation of "is this person away" is the drift `staffReadiness` was already rewritten
 * to remove one field over.
 */
    onLeave?: boolean;
    /** Whether any of this person's schedule blocks names a Location, read by the caller. */
    scheduleHasLocation?: boolean;
}

export function staffFactsFrom({
    practitioner, roles, booking, inviteAccepted, onLeave, scheduleHasLocation,
}: Input): StaffFacts {
    // ANY active role keeps the person here. Someone holding two roles with one switched off has not
    // left the practice, and "deactivated" is a sentence about a real human's job.
    const activeRoles = roles.filter((r) => r.active !== false);

    return {
        // DEFAULTS TRUE where the caller does not know. Invitation state is not on the FHIR resources
        // this reads, and inventing a `false` would put "has not signed in" on every existing staff
        // member in the practice - a page-wide false alarm is how a page stops being read. The caller
        // supplies it when it has it.
        inviteAccepted: inviteAccepted ?? true,
        hasRole: activeRoles.length > 0,
        // Location moved onto the Schedule; the role carries it only for blocks saved before that.
        hasLocation: activeRoles.some((r) => (r.location ?? []).length > 0) || scheduleHasLocation === true,
        // ONE predicate, shared with the booking resolver, the setup chain, the staff record's tab gate
        // and the reassign picker. It had been written out four times before it was extracted.
        isClinical: holdsClinicalRole(roles),
        // A MALFORMED NPI IS NOT AN NPI. A typo'd one is WORSE than an absent one for identity
        // matching ( measured three false-positive pairs in the seed data alone), so reporting
        // it as present would hide the very gap this line exists to surface.
        hasNpi: (practitioner.identifier ?? []).some(
            (id) => id.system === NPI_SYSTEM && !!id.value && isValidNpi(id.value),
        ),
        // MIRRORS THE SENDER EXACTLY, and the precision is the point. `scheduleChangeNotice.ts` picks
        // the first `telecom` whose `system` is `email` and whose value contains an `@`, and returns
        // `skipped-no-address` otherwise. Anything looser here - "has any telecom", "has a phone" -
        // would report somebody reachable whom the product will silently decline to write to, which is
        // the exact false-green this step exists to end.
        //
        // NOT the Cognito account's sign-in address. Those differ, the person signs in perfectly well,
        // and that difference is why this was invisible until a CloudWatch read found it.
        hasContact: (practitioner.telecom ?? []).some(
            (point) => point.system === 'email'
                && typeof point.value === 'string'
                && point.value.includes('@'),
        ),
        // Spencer, 2026-08-14: deactivation means GONE.
        active: activeRoles.length > 0,
        //...and AWAY is a different fact, read off the person's SCHEDULES by the caller. Defaults
        // FALSE where the caller does not know: a wrong "on leave" tells a practice a working clinician
        // is absent, which is the louder error, and the readiness line's job is to name a gap rather
        // than invent one.
        onLeave: onLeave ?? false,
        booking,
    };
}