import { describe, expect, it } from "vitest";
import {
	applyWorkspaceEvent,
	initialWorkspaceState,
	reconcileWorkspace,
	workspaceReducer,
} from "./reducer";
import type { RuntimeSnapshot, Workspace } from "./types";
const runtime = (id: string, path = "/repo") => ({
	runtimeId: id,
	worktreePath: path,
	state: "idle",
	label: id,
	attention: false,
	queueCount: 0,
	lastActivity: id,
	openedAt: id,
});
const workspace: Workspace = {
	bridgeInstanceId: "epoch",
	latestSeq: 0,
	directories: [
		{
			worktreePath: "/repo",
			isHome: false,
			openCount: 2,
			workingCount: 0,
			attentionCount: 0,
			recoveringCount: 0,
			errorCount: 0,
			runtimes: [runtime("a"), runtime("b")],
		},
	],
};

describe("workspace reducer", () => {
	it("isolates drafts, snapshots and background unread by runtime", () => {
		let state = reconcileWorkspace(initialWorkspaceState, workspace);
		state = workspaceReducer(state, {
			type: "draftChanged",
			runtimeId: "a",
			draft: "draft a",
		});
		state = workspaceReducer(state, {
			type: "snapshotRequested",
			runtimeId: "b",
			generation: 1,
		});
		const snapshot: RuntimeSnapshot = {
			bridgeInstanceId: "epoch",
			latestSeq: 0,
			runtime: runtime("b"),
			transcript: { data: { messages: [{ role: "user", content: "b" }] } },
			extensions: [],
		};
		state = workspaceReducer(state, {
			type: "snapshotLoaded",
			runtimeId: "b",
			generation: 1,
			snapshot,
		});
		state = applyWorkspaceEvent(state, {
			bridgeInstanceId: "epoch",
			seq: 1,
			type: "runtime_event",
			data: {
				runtimeId: "b",
				eventType: "transcript",
				eventData: { event: { type: "message_end" } },
			},
		});
		expect(state.runtimesById.a.draft).toBe("draft a");
		expect(state.runtimesById.a.messages).toEqual([]);
		expect(state.runtimesById.b.messages[0].content).toBe("b");
		expect(state.runtimesById.b.unread).toBe(true);
	});
	it("removes the optimistic submission when Pi returns its structured user message", () => {
		let state = reconcileWorkspace(initialWorkspaceState, workspace);
		state = workspaceReducer(state, {
			type: "submissionAdded",
			runtimeId: "a",
			submission: {
				id: 1,
				text: "Hello Pi",
				userMessageCount: 0,
				phase: "sent",
			},
		});
		state = workspaceReducer(state, {
			type: "snapshotRequested",
			runtimeId: "a",
			generation: 1,
		});
		const snapshot: RuntimeSnapshot = {
			bridgeInstanceId: "epoch",
			latestSeq: 1,
			runtime: runtime("a"),
			transcript: {
				data: {
					messages: [
						{ role: "user", content: [{ type: "text", text: "Hello Pi" }] },
					],
				},
			},
			extensions: [],
		};
		state = workspaceReducer(state, {
			type: "snapshotLoaded",
			runtimeId: "a",
			generation: 1,
			snapshot,
		});
		expect(state.runtimesById.a.pendingSubmissions).toEqual([]);
	});
	it("reconciles duplicate pending submissions one message at a time and honors Pi queue totals", () => {
		let state = reconcileWorkspace(initialWorkspaceState, workspace);
		for (const id of [1, 2])
			state = workspaceReducer(state, {
				type: "submissionAdded",
				runtimeId: "a",
				submission: {
					id,
					text: "Continue",
					userMessageCount: 0,
					phase: "sent",
				},
			});
		state = workspaceReducer(state, {
			type: "snapshotRequested",
			runtimeId: "a",
			generation: 1,
		});
		state = workspaceReducer(state, {
			type: "snapshotLoaded",
			runtimeId: "a",
			generation: 1,
			snapshot: {
				bridgeInstanceId: "epoch",
				latestSeq: 1,
				runtime: runtime("a"),
				transcript: {
					data: { messages: [{ role: "user", content: "Continue" }] },
				},
				extensions: [],
			},
		});
		expect(state.runtimesById.a.pendingSubmissions).toHaveLength(1);
		state = applyWorkspaceEvent(state, {
			bridgeInstanceId: "epoch",
			seq: 1,
			type: "runtime_event",
			data: {
				runtimeId: "a",
				eventType: "queue",
				eventData: {
					event: {
						pendingMessageCount: 3,
						followUp: ["one"],
						steering: ["two"],
					},
				},
			},
		});
		expect(state.runtimesById.a.summary.queueCount).toBe(3);
	});
	it("keeps a hotkey-triggered new-session startup visible until completion", () => {
		let state = reconcileWorkspace(initialWorkspaceState, workspace);
		state = workspaceReducer(state, {
			type: "newSessionLaunch",
			launch: { phase: "starting", detail: "Starting a new Pi session…" },
		});
		expect(state.newSessionLaunch?.phase).toBe("starting");
		state = workspaceReducer(state, {
			type: "newSessionLaunch",
			launch: undefined,
		});
		expect(state.newSessionLaunch).toBeUndefined();
	});
	it("rejects out-of-order snapshots and detects duplicate/gap/epoch events", () => {
		let state = reconcileWorkspace(initialWorkspaceState, workspace);
		state = workspaceReducer(state, {
			type: "snapshotRequested",
			runtimeId: "a",
			generation: 2,
		});
		const snap: RuntimeSnapshot = {
			bridgeInstanceId: "epoch",
			latestSeq: 0,
			runtime: runtime("a"),
			extensions: [],
		};
		expect(
			workspaceReducer(state, {
				type: "snapshotLoaded",
				runtimeId: "a",
				generation: 1,
				snapshot: snap,
			}).runtimesById.a.loading,
		).toBe(true);
		const first = applyWorkspaceEvent(state, {
			bridgeInstanceId: "epoch",
			seq: 1,
			data: { runtimeId: "a", runtime: runtime("a") },
		});
		expect(
			applyWorkspaceEvent(first, {
				bridgeInstanceId: "epoch",
				seq: 1,
				data: { runtimeId: "a" },
			}),
		).toBe(first);
		expect(
			applyWorkspaceEvent(first, {
				bridgeInstanceId: "epoch",
				seq: 3,
				data: { runtimeId: "a" },
			}).bridge.status,
		).toBe("resyncing");
		expect(
			applyWorkspaceEvent(first, {
				bridgeInstanceId: "new",
				seq: 2,
				data: { runtimeId: "a" },
			}).bridge.status,
		).toBe("resyncing");
	});
	it("selects an adjacent tab on close, preserves drafts, and keeps failed dormant runtimes", () => {
		let state = reconcileWorkspace(initialWorkspaceState, workspace, {
			version: 1,
			directoryOrder: ["/repo"],
			runtimeOrderByDirectory: { "/repo": ["b", "a"] },
			selectedRuntimeId: "b",
			drafts: { a: "saved" },
			scroll: {},
			lastSeen: {},
		});
		expect(state.runtimesById.a.draft).toBe("saved");
		state = applyWorkspaceEvent(state, {
			bridgeInstanceId: "epoch",
			seq: 1,
			type: "runtime_closed",
			data: { runtimeId: "b" },
		});
		expect(state.selectedRuntimeId).toBe("a");
		const failed: Workspace = {
			...workspace,
			directories: [
				{
					...workspace.directories[0],
					runtimes: [
						{
							...runtime("failed"),
							state: "failed",
							attention: true,
							error: { message: "missing" },
						},
					],
				},
			],
		};
		expect(
			reconcileWorkspace(initialWorkspaceState, failed).runtimesById.failed
				.summary.agentId,
		).toBeUndefined();
	});
	it("accepts fresh snapshots after a bridge epoch reset while preserving UI state", () => {
		let state = reconcileWorkspace(initialWorkspaceState, workspace);
		state = workspaceReducer(state, {
			type: "draftChanged",
			runtimeId: "a",
			draft: "keep me",
		});
		state = workspaceReducer(state, {
			type: "scrollChanged",
			runtimeId: "a",
			atBottom: false,
			scrollTop: 42,
		});
		state.runtimesById.a.loadedThroughSeq = 100;
		state = workspaceReducer(state, {
			type: "hostEvent",
			host: {
				kind: "resetRequired",
				bridgeInstanceId: "new-epoch",
				latestSeq: 2,
				reason: "epochChanged",
			},
		});
		const restored = reconcileWorkspace(state, {
			...workspace,
			bridgeInstanceId: "new-epoch",
			latestSeq: 2,
		});
		expect(restored.runtimesById.a.loadedThroughSeq).toBe(0);
		expect(restored.runtimesById.a.draft).toBe("keep me");
		expect(restored.runtimesById.a.scroll.scrollTop).toBe(42);
		const requested = workspaceReducer(restored, {
			type: "snapshotRequested",
			runtimeId: "a",
			generation: 1,
		});
		const snapshot: RuntimeSnapshot = {
			bridgeInstanceId: "new-epoch",
			latestSeq: 2,
			runtime: runtime("a"),
			extensions: [],
		};
		const accepted = workspaceReducer(requested, {
			type: "snapshotLoaded",
			runtimeId: "a",
			generation: 1,
			snapshot,
		});
		expect(accepted.runtimesById.a.loadedThroughSeq).toBe(2);
		expect(accepted.runtimesById.a.extensions).toEqual([]);
		expect(accepted.runtimesById.a.messages).toEqual([]);
	});
	it("clears stale extension and transcript state for every runtime after an epoch change", () => {
		const state = reconcileWorkspace(initialWorkspaceState, workspace);
		state.runtimesById.b.messages = [{ role: "assistant", content: "old" }];
		state.runtimesById.b.extensions = [
			{ id: "dead-request", method: "confirm" },
		];
		state.runtimesById.b.unread = true;
		const reset = workspaceReducer(state, {
			type: "hostEvent",
			host: {
				kind: "resetRequired",
				bridgeInstanceId: "new-epoch",
				latestSeq: 1,
				reason: "epochChanged",
			},
		});
		const restored = reconcileWorkspace(reset, {
			...workspace,
			bridgeInstanceId: "new-epoch",
			latestSeq: 1,
		});
		expect(restored.runtimesById.b.messages).toEqual([]);
		expect(restored.runtimesById.b.extensions).toEqual([]);
		expect(restored.runtimesById.b.unread).toBe(false);
	});
	it("requests reconciliation when a runtime lifecycle event changes the open tabs", () => {
		const state = reconcileWorkspace(initialWorkspaceState, workspace);
		const next = applyWorkspaceEvent(state, {
			bridgeInstanceId: "epoch",
			seq: 1,
			type: "runtime_opened",
			data: { runtimeId: "external", runtime: runtime("external") },
		});
		expect(next.bridge.status).toBe("resyncing");
	});
	it("clears unread only when selected, active, and at latest", () => {
		let state = reconcileWorkspace(initialWorkspaceState, workspace);
		state.runtimesById.a.unread = true;
		state = workspaceReducer(state, { type: "setWindowActive", active: false });
		state = workspaceReducer(state, { type: "markRead", runtimeId: "a" });
		expect(state.runtimesById.a.unread).toBe(true);
		state = workspaceReducer(state, { type: "setWindowActive", active: true });
		state = workspaceReducer(state, {
			type: "scrollChanged",
			runtimeId: "a",
			atBottom: false,
		});
		state = workspaceReducer(state, { type: "markRead", runtimeId: "a" });
		expect(state.runtimesById.a.unread).toBe(true);
		state = workspaceReducer(state, {
			type: "scrollChanged",
			runtimeId: "a",
			atBottom: true,
		});
		state = workspaceReducer(state, { type: "markRead", runtimeId: "a" });
		expect(state.runtimesById.a.unread).toBe(false);
	});
});