Restructure

src-angular/app/core/services/search.service.ts

@@ -0,0 +1,119 @@
+import { EventEmitter, Injectable } from '@angular/core'
+
+import { SongResult, SongSearch } from 'src/electron/shared/interfaces/search.interface'
+import { VersionResult } from 'src/electron/shared/interfaces/songDetails.interface'
+import { ElectronService } from './electron.service'
+
+@Injectable({
+	providedIn: 'root',
+})
+export class SearchService {
+
+	private resultsChangedEmitter = new EventEmitter<SongResult[]>() // For when any results change
+	private newResultsEmitter = new EventEmitter<SongResult[]>()     // For when a new search happens
+	private errorStateEmitter = new EventEmitter<boolean>()          // To indicate the search's error state
+	private results: SongResult[] = []
+	private awaitingResults = false
+	private currentQuery: SongSearch
+	private _allResultsVisible = true
+
+	constructor(private electronService: ElectronService) { }
+
+	async newSearch(query: SongSearch) {
+		if (this.awaitingResults) { return }
+		this.awaitingResults = true
+		this.currentQuery = query
+		try {
+			this.results = this.trimLastChart(await this.electronService.invoke('song-search', this.currentQuery))
+			this.errorStateEmitter.emit(false)
+		} catch (err) {
+			this.results = []
+			console.log(err.message)
+			this.errorStateEmitter.emit(true)
+		}
+		this.awaitingResults = false
+
+		this.newResultsEmitter.emit(this.results)
+		this.resultsChangedEmitter.emit(this.results)
+	}
+
+	isLoading() {
+		return this.awaitingResults
+	}
+
+	/**
+	 * Event emitted when new search results are returned
+	 * or when more results are added to an existing search.
+	 * (emitted after `onNewSearch`)
+	 */
+	onSearchChanged(callback: (results: SongResult[]) => void) {
+		this.resultsChangedEmitter.subscribe(callback)
+	}
+
+	/**
+	 * Event emitted when a new search query is typed in.
+	 * (emitted before `onSearchChanged`)
+	 */
+	onNewSearch(callback: (results: SongResult[]) => void) {
+		this.newResultsEmitter.subscribe(callback)
+	}
+
+	/**
+	 * Event emitted when the error state of the search changes.
+	 * (emitted before `onSearchChanged`)
+	 */
+	onSearchErrorStateUpdate(callback: (isError: boolean) => void) {
+		this.errorStateEmitter.subscribe(callback)
+	}
+
+	get resultCount() {
+		return this.results.length
+	}
+
+	async updateScroll() {
+		if (!this.awaitingResults && !this._allResultsVisible) {
+			this.awaitingResults = true
+			this.currentQuery.offset += 50
+			this.results.push(...this.trimLastChart(await this.electronService.invoke('song-search', this.currentQuery)))
+			this.awaitingResults = false
+
+			this.resultsChangedEmitter.emit(this.results)
+		}
+	}
+
+	trimLastChart(results: SongResult[]) {
+		if (results.length > 50) {
+			results.splice(50, 1)
+			this._allResultsVisible = false
+		} else {
+			this._allResultsVisible = true
+		}
+
+		return results
+	}
+
+	get allResultsVisible() {
+		return this._allResultsVisible
+	}
+
+	/**
+	 * Orders `versionResults` by lastModified date, but prefer the
+	 * non-pack version if it's only a few days older.
+	 */
+	sortChart(versionResults: VersionResult[]) {
+		const dates: { [versionID: number]: number } = {}
+		versionResults.forEach(version => dates[version.versionID] = new Date(version.lastModified).getTime())
+		versionResults.sort((v1, v2) => {
+			const diff = dates[v2.versionID] - dates[v1.versionID]
+			if (Math.abs(diff) < 6.048e+8 && v1.driveData.inChartPack != v2.driveData.inChartPack) {
+				if (v1.driveData.inChartPack) {
+					return 1 // prioritize v2
+				} else {
+					return -1 // prioritize v1
+				}
+			} else {
+				return diff
+			}
+		})
+	}
+}