import type { ThreadListingState } from '../../services';

// Search filters rows without changing listing authority or completeness.
// Refused, pending, unknown, failed and partial remain distinct, in that priority order.
export type ThreadListingRank = 'refused' | 'pending' | 'unknown' | 'failed' | 'partial' | 'complete';

export interface ThreadListingRankInput {
    state: ThreadListingState;
    /** The current acting-as refusal. Staff have no helper grant to refuse, so this is patient-only. */
    refused?: boolean;
    /** A no-practice helper's own grant: 'pending' while it is read, 'unknown' when it could not be. */
    helperGrantState?: 'pending' | 'unknown';
}

export const rankThreadListing = ({ state, refused, helperGrantState }: ThreadListingRankInput): ThreadListingRank => {
    if (refused) return 'refused';
    if (helperGrantState === 'pending' || state === 'pending') return 'pending';
    if (state === 'unknown') return 'unknown';
    if (state === 'failed' || helperGrantState === 'unknown') return 'failed';
    if (state === 'partial') return 'partial';
    return 'complete';
};

/** The inline notice to show beside rows already on screen. `undefined` for a known-complete list. */
export const rowsNoticeFor = (rank: ThreadListingRank): { text: string; retry: boolean } | undefined => {
    switch (rank) {
        case 'pending':
            return { text: 'Checking your access to these messages', retry: false };
        case 'unknown':
            return { text: 'Checking for new conversations', retry: false };
        case 'failed':
            return { text: 'Some conversations could not be loaded. What is shown may be out of date.', retry: true };
        case 'partial':
            return { text: 'Some conversations could not be loaded.', retry: true };
        default:
            return undefined;
    }
};