import XCTest
@testable import honeyDue

/// Tests for the per-residence widget filter added in gitea#6.
///
/// `WidgetDataManager.filterTasks(_:forResidenceId:)` is the pure
/// function the widget timeline provider calls when a configuration
/// intent has a residence selected. These tests guarantee the contract
/// stays stable: nil → pass-through, matching id → only matching tasks,
/// no match → empty, missing residenceId on a task → never leaks into
/// a residence-scoped widget.
final class WidgetResidenceFilterTests: XCTestCase {

    private func makeTask(
        id: Int,
        residenceId: Int? = nil
    ) -> WidgetDataManager.WidgetTask {
        WidgetDataManager.WidgetTask(
            id: id,
            title: "Task \(id)",
            description: nil,
            priority: nil,
            inProgress: false,
            dueDate: nil,
            category: nil,
            residenceId: residenceId,
            residenceName: nil,
            isOverdue: false,
            isDueWithin7Days: false,
            isDue8To30Days: false
        )
    }

    func testNilResidenceReturnsAllTasks() {
        // "All residences" config — widget passes nil, gets every task.
        let tasks = [
            makeTask(id: 1, residenceId: 10),
            makeTask(id: 2, residenceId: 20),
            makeTask(id: 3, residenceId: nil),
        ]
        let result = WidgetDataManager.filterTasks(tasks, forResidenceId: nil)
        XCTAssertEqual(result.map(\.id), [1, 2, 3])
    }

    func testMatchingResidenceKeepsOnlyMatchingTasks() {
        let tasks = [
            makeTask(id: 1, residenceId: 10),
            makeTask(id: 2, residenceId: 20),
            makeTask(id: 3, residenceId: 10),
            makeTask(id: 4, residenceId: 30),
        ]
        let result = WidgetDataManager.filterTasks(tasks, forResidenceId: 10)
        XCTAssertEqual(result.map(\.id), [1, 3])
    }

    func testUnknownResidenceReturnsEmpty() {
        let tasks = [
            makeTask(id: 1, residenceId: 10),
            makeTask(id: 2, residenceId: 20),
        ]
        let result = WidgetDataManager.filterTasks(tasks, forResidenceId: 999)
        XCTAssertTrue(result.isEmpty)
    }

    func testNilResidenceIdOnTaskDoesNotMatchScopedConfiguration() {
        // A task written by an older app build (no `residence_id` in JSON)
        // must NOT leak into a residence-scoped widget — we'd rather hide
        // it than misattribute it to the wrong home.
        let tasks = [
            makeTask(id: 1, residenceId: 10),
            makeTask(id: 2, residenceId: nil),
        ]
        let result = WidgetDataManager.filterTasks(tasks, forResidenceId: 10)
        XCTAssertEqual(result.map(\.id), [1])
    }

    func testFilterPreservesInputOrder() {
        // The filter is a pure subset op — no sorting side effects.
        // Timeline provider relies on this so its sort step (overdue
        // first, then by due date) operates on already-filtered tasks.
        let tasks = [
            makeTask(id: 5, residenceId: 1),
            makeTask(id: 3, residenceId: 1),
            makeTask(id: 7, residenceId: 1),
            makeTask(id: 1, residenceId: 2),
        ]
        let result = WidgetDataManager.filterTasks(tasks, forResidenceId: 1)
        XCTAssertEqual(result.map(\.id), [5, 3, 7])
    }
}