add legislation API client for frontend

src/client/features/legislation/lib/legislation-api.test.ts

@@ -0,0 +1,72 @@
+import { beforeEach, describe, expect, it, vi } from "vitest"
+
+const mockFetch = vi.fn()
+vi.stubGlobal("fetch", mockFetch)
+
+const { fetchLegislation, castVote, fetchUserVote } = await import(
+	"./legislation-api"
+)
+
+describe("legislation-api", () => {
+	beforeEach(() => {
+		mockFetch.mockReset()
+	})
+
+	it("fetches legislation detail", async () => {
+		mockFetch.mockResolvedValueOnce(
+			new Response(
+				JSON.stringify({
+					id: 1,
+					dipVorgangsId: 100,
+					title: "Test Gesetz",
+					abstract: "Summary",
+					fullText: null,
+					summary: null,
+					fetchedAt: "2026-03-10T00:00:00Z",
+				}),
+			),
+		)
+
+		const result = await fetchLegislation(1)
+		expect(result.title).toBe("Test Gesetz")
+	})
+
+	it("casts a vote", async () => {
+		mockFetch.mockResolvedValueOnce(
+			new Response(JSON.stringify({ ok: true }), { status: 201 }),
+		)
+
+		await castVote(1, "device-123", "ja")
+		expect(mockFetch).toHaveBeenCalledOnce()
+		const [url, opts] = mockFetch.mock.calls[0]
+		expect(url).toContain("/legislation/1/vote")
+		expect(opts.method).toBe("POST")
+	})
+
+	it("fetches existing user vote", async () => {
+		mockFetch.mockResolvedValueOnce(
+			new Response(
+				JSON.stringify({
+					legislationId: 1,
+					vote: "ja",
+					votedAt: "2026-03-10T00:00:00Z",
+				}),
+			),
+		)
+
+		const result = await fetchUserVote(1, "device-123")
+		expect(result).not.toBeNull()
+		expect(result?.vote).toBe("ja")
+	})
+
+	it("returns null when no user vote exists (404)", async () => {
+		mockFetch.mockResolvedValueOnce(
+			new Response(JSON.stringify({ error: "no vote found" }), {
+				status: 404,
+			}),
+		)
+
+		const result = await fetchUserVote(1, "device-123")
+		expect(result).toBeNull()
+	})
+})

src/client/features/legislation/lib/legislation-api.ts

@@ -0,0 +1,45 @@
+import { BACKEND_URL } from "@/shared/lib/constants"
+import type {
+	LegislationDetail,
+	UserVoteChoice,
+	UserVoteRecord,
+} from "../../../../shared/legislation-types"
+
+export async function fetchLegislation(id: number): Promise<LegislationDetail> {
+	const res = await fetch(`${BACKEND_URL}/legislation/${id}`)
+	if (!res.ok) throw new Error(`Failed to fetch legislation ${id}`)
+	return res.json()
+}
+
+export async function fetchLegislationText(id: number): Promise<string | null> {
+	const res = await fetch(`${BACKEND_URL}/legislation/${id}/text`)
+	if (!res.ok) return null
+	const data = await res.json()
+	return data.text ?? null
+}
+
+export async function castVote(
+	legislationId: number,
+	deviceId: string,
+	vote: UserVoteChoice,
+): Promise<void> {
+	const res = await fetch(`${BACKEND_URL}/legislation/${legislationId}/vote`, {
+		method: "POST",
+		headers: { "Content-Type": "application/json" },
+		body: JSON.stringify({ deviceId, vote }),
+	})
+	if (!res.ok)
+		throw new Error(`Failed to cast vote for legislation ${legislationId}`)
+}
+
+export async function fetchUserVote(
+	legislationId: number,
+	deviceId: string,
+): Promise<UserVoteRecord | null> {
+	const res = await fetch(
+		`${BACKEND_URL}/legislation/${legislationId}/vote/${deviceId}`,
+	)
+	if (res.status === 404) return null
+	if (!res.ok) throw new Error("Failed to fetch vote")
+	return res.json()
+}