Implemented phase 5 for the POC prototype in the Website service.

Services/Website/Sources/Library/Public/Controllers/CollectingController.swift

@@ -0,0 +1,295 @@
+import Foundation
+import Hummingbird
+import HummingbirdElementary
+import Infrastructure
+import Persistence
+
+/// Serves what a collector uses: the want list, for a signed-in account, and the public series screens and comparison.
+///
+/// - Note: `Context` is the request context the routes are resolved against, and must match the context of the router the routes are added to.
+public struct CollectingController<Context: RequestContext> {
+
+    // MARK: Properties
+
+    private let analytics: Analytics?
+    private let assetVersion: String?
+
+    /// The repository listings are read through.
+    private let catalogue: CatalogueRepository
+
+    /// The repository wants and series are read and written through.
+    private let collecting: CollectingRepository
+
+    /// The store the signed-in account is read from.
+    private let sessions: SessionStore
+
+    // MARK: Initializers
+
+    /// Creates a collecting controller.
+    /// - Parameters:
+    ///   - collecting: the repository wants and series are read and written through.
+    ///   - catalogue: the repository listings are read through.
+    ///   - sessions: the store the signed-in account is read from.
+    ///   - assetVersion: the version token appended to the pages' asset URLs, or `nil` (the default) to leave them unversioned.
+    ///   - analytics: the analytics tracker the pages embed, or `nil` (the default) to omit it.
+    public init(
+        collecting: CollectingRepository,
+        catalogue: CatalogueRepository,
+        sessions: SessionStore,
+        assetVersion: String? = nil,
+        analytics: Analytics? = nil
+    ) {
+        self.analytics = analytics
+        self.assetVersion = assetVersion
+        self.catalogue = catalogue
+        self.collecting = collecting
+        self.sessions = sessions
+    }
+
+}
+
+// MARK: - RouterController
+
+extension CollectingController: RouterController {
+
+    // MARK: Properties
+
+    public var routes: RouteCollection<Context> {
+        let routes = RouteCollection(context: Context.self)
+
+        routes.get(.init(.Route.wants), use: wants)
+        routes.post(.init(.Route.wants), use: addWant)
+        routes.get(.init("\(String.Route.wants)/new"), use: newWant)
+        routes.post(.init("\(String.Route.wants)/:id/alerts"), use: toggleAlerts)
+        routes.post(.init("\(String.Route.wants)/:id/remove"), use: removeWant)
+        routes.get(.init(.Route.series), use: seriesIndex)
+        routes.get(.init("\(String.Route.series)/:slug"), use: series)
+        routes.get(.init(.Route.compare), use: compare)
+
+        return routes
+    }
+
+}
+
+// MARK: - Wants
+
+private extension CollectingController {
+
+    /// Handles a want posted from the form.
+    @Sendable
+    func addWant(
+        request: Request,
+        context: Context
+    ) async throws -> Response {
+        guard let user = await sessions.user(for: request) else {
+            return .redirect(to: .Route.signIn(returningTo: .Route.wants), type: .normal)
+        }
+
+        let form = try await URLEncodedFormDecoder().decode(WantForm.self, from: request, context: context)
+
+        try await collecting.addWant(
+            title: form.title,
+            minGrade: form.minGrade.flatMap(Double.init),
+            maxPriceCents: form.maxPrice.flatMap { Int($0.trimmingCharacters(in: .whitespaces)) }.flatMap { $0 > 0 ? $0 * 100 : nil },
+            slabbedOnly: form.slabbed == "1",
+            for: user
+        )
+
+        return .redirect(to: .Route.wants, type: .normal)
+    }
+
+    /// Handles a request for the add-a-want form, filled from a listing being saved, or with a title — a gap in a series.
+    @Sendable
+    func newWant(
+        request: Request,
+        context: Context
+    ) async throws -> Response {
+        guard let user = await sessions.user(for: request) else {
+            return .redirect(to: .Route.signIn(returningTo: request.uri.string), type: .found)
+        }
+
+        var draft = WantsPage.Draft(title: request.uri.queryParameters.get("title") ?? "")
+
+        if
+            let slug = request.uri.queryParameters.get("listing"),
+            let listing = try await catalogue.listing(slug: slug)
+        {
+            draft = .init(title: listing.title, minGrade: listing.grade, maxPriceCents: listing.priceCents)
+        }
+
+        return try await wantsPage(user, draft: draft, request: request, context: context)
+    }
+
+    /// Handles the removal of one of the account's wants.
+    @Sendable
+    func removeWant(
+        request: Request,
+        context: Context
+    ) async throws -> Response {
+        guard let user = await sessions.user(for: request) else {
+            return .redirect(to: .Route.signIn(returningTo: .Route.wants), type: .normal)
+        }
+
+        if let id = context.parameters.get("id", as: UUID.self) {
+            try await collecting.removeWant(id, of: user)
+        }
+
+        return .redirect(to: .Route.wants, type: .normal)
+    }
+
+    /// Handles the switching of a want's alerts.
+    @Sendable
+    func toggleAlerts(
+        request: Request,
+        context: Context
+    ) async throws -> Response {
+        guard let user = await sessions.user(for: request) else {
+            return .redirect(to: .Route.signIn(returningTo: .Route.wants), type: .normal)
+        }
+
+        if let id = context.parameters.get("id", as: UUID.self) {
+            try await collecting.toggleAlerts(ofWant: id, of: user)
+        }
+
+        return .redirect(to: .Route.wants, type: .normal)
+    }
+
+    /// Handles a request for the want list. Looking at it is what makes its matches no longer new.
+    @Sendable
+    func wants(
+        request: Request,
+        context: Context
+    ) async throws -> Response {
+        guard let user = await sessions.user(for: request) else {
+            return .redirect(to: .Route.signIn(returningTo: .Route.wants), type: .found)
+        }
+
+        return try await wantsPage(user, draft: nil, request: request, context: context)
+    }
+
+    /// Renders the want list with its matches still marked new, then marks them seen — so the header's bell is quiet on the next page.
+    func wantsPage(
+        _ user: User,
+        draft: WantsPage.Draft?,
+        request: Request,
+        context: Context
+    ) async throws -> Response {
+        let wants = try await collecting.wants(of: user)
+
+        try await collecting.markWantsSeen(by: user)
+
+        let viewer = await sessions.viewer(for: request)
+
+        return HTMLResponse(additionalHeaders: .perViewer) { [analytics, assetVersion] in
+            WantsPage(
+                wants: wants,
+                draft: draft,
+                viewer: viewer,
+                assetVersion: assetVersion,
+                analytics: analytics
+            )
+        }
+        .response(from: request, context: context)
+    }
+
+}
+
+// MARK: - Series
+
+private extension CollectingController {
+
+    /// Handles a request for the comparison of the copies named in the query, up to three.
+    @Sendable
+    func compare(
+        request: Request,
+        context: Context
+    ) async throws -> HTMLResponse {
+        var copies = [Listing]()
+
+        for slug in request.uri.queryParameters.getAll("copy").prefix(SeriesPage.maxCompared) {
+            if let copy = try await catalogue.listing(slug: slug), copy.isAvailable {
+                copies.append(copy)
+            }
+        }
+
+        let viewer = await sessions.viewer(for: request)
+
+        return .init(additionalHeaders: .perViewer) { [analytics, assetVersion, copies] in
+            ComparePage(
+                copies: copies,
+                viewer: viewer,
+                assetVersion: assetVersion,
+                analytics: analytics
+            )
+        }
+    }
+
+    /// Handles a request for a series; an unknown slug is not found.
+    @Sendable
+    func series(
+        request: Request,
+        context: Context
+    ) async throws -> HTMLResponse {
+        let slug = try context.parameters.require("slug")
+
+        guard let series = try await collecting.series(slug: slug) else {
+            throw HTTPError(.notFound)
+        }
+
+        // Every copy of the series, wherever it ships from: a series screen is the whole market for it.
+        let listings = try await catalogue.listings().filter { $0.seriesSlug == slug }
+        let issue = request.uri.queryParameters.get("issue", as: Int.self)
+        let viewer = await sessions.viewer(for: request)
+
+        return .init(additionalHeaders: .perViewer) { [analytics, assetVersion] in
+            SeriesPage(
+                series: series,
+                listings: listings,
+                issue: issue,
+                viewer: viewer,
+                assetVersion: assetVersion,
+                analytics: analytics
+            )
+        }
+    }
+
+    /// Handles a request for the series index.
+    @Sendable
+    func seriesIndex(
+        request: Request,
+        context: Context
+    ) async throws -> HTMLResponse {
+        let listings = try await catalogue.listings()
+        let entries = try await collecting.allSeries().map { series in
+            (series, listings.filter { $0.seriesSlug == series.slug })
+        }
+        let viewer = await sessions.viewer(for: request)
+
+        return .init(additionalHeaders: .perViewer) { [analytics, assetVersion] in
+            SeriesIndexPage(
+                entries: entries,
+                viewer: viewer,
+                assetVersion: assetVersion,
+                analytics: analytics
+            )
+        }
+    }
+
+}
+
+// MARK: - Structs
+
+/// The fields the add-a-want form posts.
+private struct WantForm: Decodable {
+    let title: String
+    let minGrade: String?
+    let maxPrice: String?
+    let slabbed: String?
+
+    enum CodingKeys: String, CodingKey {
+        case title
+        case minGrade = "min-grade"
+        case maxPrice = "max-price"
+        case slabbed
+    }
+}