// The case-conference entry point: a collaboration team's practitioners conferring ABOUT a patient,
// with the patient not present.
//
// IT LIVES HERE, NOT IN `StaffCareTeamsPage.tsx`, ON PURPOSE. That page is a shared file other
// sessions restyle, so diff there is one import and one element - every video concern
// (the ship gate, the busy-elsewhere rule, the context prefix) is in this file instead.
//
// THE PATIENT IS EXCLUDED SERVER-SIDE, and that is where it has to be. A `collabteam#`
// session's roster is filtered to the team's PRACTITIONERS before the membership test, so the subject
// patient is neither notified, nor admitted on join, nor shown the session in their own late-joiner
// list. Hiding a button could only ever have closed the first of those three.
import { Video } from 'lucide-react';
import { useVideoServiceContext } from '../../services/VideoService';
import { collabTeamContext } from '../../services/video/videoContract';
import { TELEHEALTH_VIDEO_ENABLED } from '../../services/video/videoFlags';
import { caseConferenceEntry } from './caseConferenceEntry';

interface Props { teamId: string }

export const StartCaseConferenceButton: React.FC<Props> = ({ teamId }) => {
    const { call, startCall, joinAvailable } = useVideoServiceContext();

    // WHICH DOOR THIS OPENS. Offering Start over a conference this team already has sends the
    // practitioner at the create route, which the server refuses 409 `CONTEXT_TAKEN` - while the
    // join route answers on the same session and token. This is the client stopping short of a
    // request that is certain to be refused, NOT a gate: the server still decides, and its refusal
    // still renders if it comes.
    const entry = caseConferenceEntry({
        teamId,
        phase: call.phase,
        callContext: call.context,
        available: call.available,
    });
    const rejoining = entry.kind === 'join' || entry.kind === 'rejoin';

    // Starting a second call auto-leaves the first - `ChimeCallSession.join()` tears the previous
    // meeting down before building the next - so an enabled control here would silently drop a live
    // visit somebody is sitting in. Anchored on `idle` so a phase added later fails SAFE (refuses)
    // rather than permitting a start mid-teardown. Same rule `EncounterVideoPane` carries.
    // `live` is this team's own conference already up on this screen - there is nothing to offer.
    const busy = entry.kind === 'live' || call.phase !== 'idle';

    // THE SHIP GATE, on the ENTRY POINT only - never on call chrome, which would strand a
    // participant inside a meeting with no controls. Visible-and-disabled rather than hidden
    // (Spencer, ): an absent control reads as "this product has no telehealth", a disabled
    // one reads as "not yet".
    const gated = !TELEHEALTH_VIDEO_ENABLED;

    return (
        <button
            type="button"
            className="btn btn-blue shrink-0"
            disabled={gated || busy}
            title={gated
                ? 'Video visits are coming soon.'
                : busy ? 'Another video meeting is in progress.' : undefined}
            // A `collabteam#` context, never an `encounter#` one. The server reads this prefix to
            // decide WHOSE roster gates the meeting; the two contexts have deliberately opposite
            // rules about the patient.
            onClick={() => (rejoining
                ? void joinAvailable()
                : void startCall(collabTeamContext(teamId)))}
        >
            <Video className="w-4 h-4" />
            {entry.kind === 'rejoin'
                ? 'Rejoin the case conference'
                : entry.kind === 'join' ? 'Join the case conference' : 'Start case conference'}
        </button>
    );
};