import type { Fn , IObjectOf } from "@thi.ng/api" ; import { isArray } from "@thi.ng/checks/is-array" ; import { identity } from "@thi.ng/compose/identity" ; import { illegalState } from "@thi.ng/errors/illegal-state" ; import type { Reducer , Transducer } from "./api.js" ; import { __iter , iterator } from "./iterator.js" ; import { isReduced } from "./reduced.js" ; export interface PartitionSync < T > extends Transducer < T , IObjectOf < T > > { /**
     * Returns set of currently required input IDs.
     */ keys ( ) : Set < PropertyKey > ; /**
     * Removes all inputs and clears received values.
     */ clear ( ) : void ; param id add ( id ) : void ; param id param clean delete ( id , clean ? ) : void ; } export interface PartitionSyncOpts < T > { key : Fn < T , PropertyKey > ; mergeOnly : boolean ; reset : boolean ; all : boolean ; /**
     * If greater than 0, then each labeled input will cache upto the
     * stated number of input values, even if other inputs have not yet
     * produced new values. Once the limit is reached, `partitionSync()`
     * will throw an `IllegalState` error.
     *
     * Enabling this option will cause the same behavior as if `reset`
     * is enabled (regardless of the actual configured `reset` setting).
     * I.e. new results are only produced when ALL required inputs have
     * available values...
     */ backPressure : number ; } remarks example param keys param keyfn param reset param all export function partitionSync < T > ( keys , opts ? ) ; export function partitionSync < T > ( keys , src ) ; export function partitionSync < T > ( keys , opts , src ) ; export function partitionSync < T > ( ... args ) { const iter = __iter ( partitionSync , args , iterator ) ; if ( iter ) return iter ; const { key , mergeOnly , reset , all , backPressure } = < PartitionSyncOpts < T > > { key : < any > identity , mergeOnly : false , reset : true , all : true , backPressure : 0 , ... args [ 1 ] , } ; const requiredKeys = isArray ( args [ 0 ] ) ? new Set ( args [ 0 ] ) : args [ 0 ] ; const currKeys = new Set < PropertyKey > ( ) ; const cache = new Map ( ) ; let curr = { } ; const xform = ( [ init , complete , reduce ] ) => { let first = true ; if ( mergeOnly || backPressure < 1 ) { return < Reducer < any , T > > [ init , ( acc ) => { if ( ( reset && all && currKeys . size > 0 ) || ( ! reset && first ) ) { acc = reduce ( acc , curr ) ; curr = { } ; currKeys . clear ( ) ; first = false ; } return complete ( acc ) ; } , ( acc , x ) => { const k = key ( x ) ; if ( requiredKeys . has ( k ) ) { curr [ < any > k ] = x ; currKeys . add ( k ) ; if ( mergeOnly || requiredInputs ( requiredKeys , currKeys ) ) { acc = reduce ( acc , curr ) ; first = false ; if ( reset ) { curr = { } ; currKeys . clear ( ) ; } else { curr = { ... curr } ; } } } return acc ; } , ] ; } else { return < Reducer < any , T > > [ init , ( acc ) => { if ( all && currKeys . size > 0 ) { acc = reduce ( acc , collect ( cache , currKeys ) ) ; cache . clear ( ) ; currKeys . clear ( ) ; } return complete ( acc ) ; } , ( acc , x ) => { const k = key ( x ) ; if ( requiredKeys . has ( k ) ) { let slot = cache . get ( k ) ; ! slot && cache . set ( k , ( slot = [ ] ) ) ; slot . length >= backPressure && illegalState ( `max back pressure (${ backPressure }) exceeded for input: ${ String ( k ) }` ) ; slot . push ( x ) ; currKeys . add ( k ) ; while ( requiredInputs ( requiredKeys , currKeys ) ) { acc = reduce ( acc , collect ( cache , currKeys ) ) ; first = false ; if ( isReduced ( acc ) ) break ; } } return acc ; } , ] ; } } ; xform . keys = ( ) => requiredKeys ; xform . clear = ( ) => { cache . clear ( ) ; requiredKeys . clear ( ) ; currKeys . clear ( ) ; curr = { } ; } ; xform . add = ( id ) => { requiredKeys . add ( id ) ; } ; xform . delete = ( id , clean = true ) => { cache . delete ( id ) ; requiredKeys . delete ( id ) ; if ( clean ) { currKeys . delete ( id ) ; delete curr [ < any > id ] ; } } ; return xform ; } const requiredInputs = ( required , curr ) => { if ( curr . size < required . size ) return false ; for ( let id of required ) { if ( ! curr . has ( id ) ) return false ; } return true ; } ; const collect = < T > ( cache , currKeys ) => { const curr = { } ; for ( let id of currKeys ) { const slot = cache . get ( id ) ! ; curr [ < any > id ] = slot . shift ( ) ! ; ! slot . length && currKeys . delete ( id ) ; } return curr ; } ;