//
//  TravelAlbumAIRetouchTemplateViewModelTests.swift
//  suixinkanTests
//

import XCTest
@testable import suixinkan

/// AI 修图模板选择状态测试。
@MainActor
final class TravelAlbumAIRetouchTemplateViewModelTests: XCTestCase {
    func testLoadDefaultsRequiredSelectionsAndLeavesAtmosphereEmpty() async {
        let api = makeAPI()
        let viewModel = TravelAlbumAIRetouchTemplateViewModel(
            albumId: 8,
            scenicId: 18,
            materialIds: [4, 3, 2, 1]
        )

        await viewModel.loadTemplates(api: api)

        XCTAssertEqual(api.aiRetouchTemplateScenicIds, [18])
        XCTAssertEqual(viewModel.selectedRefinedTemplateId, 11)
        XCTAssertNil(viewModel.selectedAtmosphereTemplateId)
        XCTAssertEqual(viewModel.selectedCoverTemplateId, 31)
        XCTAssertTrue(viewModel.showsCoverTemplates)
        XCTAssertTrue(viewModel.canSubmit)
    }

    func testAtmosphereSelectionTogglesOffWhenTappedAgain() async {
        let api = makeAPI()
        let viewModel = TravelAlbumAIRetouchTemplateViewModel(
            albumId: 8,
            scenicId: 18,
            materialIds: [1]
        )
        await viewModel.loadTemplates(api: api)

        viewModel.toggleTemplate(id: 21, category: .atmosphere)
        XCTAssertEqual(viewModel.selectedAtmosphereTemplateId, 21)

        viewModel.toggleTemplate(id: 21, category: .atmosphere)
        XCTAssertNil(viewModel.selectedAtmosphereTemplateId)
    }

    func testThreeMaterialsHideCoverAndOmitCoverFromSubmission() async {
        let api = makeAPI()
        let viewModel = TravelAlbumAIRetouchTemplateViewModel(
            albumId: 8,
            scenicId: 18,
            materialIds: [3, 1, 2]
        )
        var submitted = false
        viewModel.onSubmitted = { submitted = true }
        await viewModel.loadTemplates(api: api)

        XCTAssertFalse(viewModel.showsCoverTemplates)
        XCTAssertNil(viewModel.selectedCoverTemplateId)

        await viewModel.submit(api: api)

        XCTAssertTrue(submitted)
        XCTAssertEqual(api.aiRetouchRequests.count, 1)
        XCTAssertEqual(api.aiRetouchRequests.first?.materialIds, [1, 2, 3])
        XCTAssertNil(api.aiRetouchRequests.first?.aiPreviewTabs)
    }

    func testFourMaterialsSubmitAllSelectedTemplateIds() async {
        let api = makeAPI()
        let viewModel = TravelAlbumAIRetouchTemplateViewModel(
            albumId: 8,
            scenicId: 18,
            materialIds: [1, 2, 3, 4]
        )
        await viewModel.loadTemplates(api: api)
        viewModel.toggleTemplate(id: 12, category: .refined)
        viewModel.toggleTemplate(id: 21, category: .atmosphere)

        await viewModel.submit(api: api)

        XCTAssertEqual(
            api.aiRetouchRequests.first,
            TravelAlbumAIRetouchRequest(
                userEquityTravelId: 8,
                materialIds: [1, 2, 3, 4],
                refinedTemplateId: 12,
                atmosphereTemplateId: 21,
                aiPreviewTabs: 31
            )
        )
    }

    func testMissingRequiredCoverTemplateDisablesSubmission() async {
        let api = makeAPI()
        api.aiRetouchTemplatesResponse = TravelAlbumAIRetouchTemplatesResponse(
            refinedTemplates: [template(11, "清透")],
            atmosphereTemplates: [template(21, "暖阳")],
            coverTemplates: []
        )
        let viewModel = TravelAlbumAIRetouchTemplateViewModel(
            albumId: 8,
            scenicId: 18,
            materialIds: [1, 2, 3, 4]
        )

        await viewModel.loadTemplates(api: api)

        XCTAssertFalse(viewModel.canSubmit)
        XCTAssertEqual(viewModel.validationMessage, "暂无可用的封面风格模板")
    }

    func testLoadFailureExposesRetryMessageAndKeepsSubmissionDisabled() async {
        let api = makeAPI()
        api.aiRetouchTemplatesError = APIError.serverCode(500, "模板服务繁忙")
        let viewModel = TravelAlbumAIRetouchTemplateViewModel(
            albumId: 8,
            scenicId: 18,
            materialIds: [1]
        )

        await viewModel.loadTemplates(api: api)

        XCTAssertEqual(viewModel.loadErrorMessage, "模板服务繁忙")
        XCTAssertFalse(viewModel.canSubmit)
        XCTAssertTrue(viewModel.refinedTemplates.isEmpty)
    }

    func testSubmitFailureKeepsSelectionAndAllowsRetry() async {
        let api = makeAPI()
        api.submitAIRetouchError = APIError.serverCode(500, "提交服务繁忙")
        let viewModel = TravelAlbumAIRetouchTemplateViewModel(
            albumId: 8,
            scenicId: 18,
            materialIds: [1]
        )
        var message: String?
        var submitted = false
        viewModel.onShowMessage = { message = $0 }
        viewModel.onSubmitted = { submitted = true }
        await viewModel.loadTemplates(api: api)

        await viewModel.submit(api: api)

        XCTAssertEqual(api.aiRetouchRequests.count, 1)
        XCTAssertEqual(message, "提交服务繁忙")
        XCTAssertFalse(submitted)
        XCTAssertFalse(viewModel.isSubmitting)
        XCTAssertTrue(viewModel.canSubmit)
        XCTAssertEqual(viewModel.selectedRefinedTemplateId, 11)
    }

    func testSubmittingPreventsDuplicateRequest() async {
        let api = makeAPI()
        api.submitAIRetouchDelayNanoseconds = 50_000_000
        let viewModel = TravelAlbumAIRetouchTemplateViewModel(
            albumId: 8,
            scenicId: 18,
            materialIds: [1]
        )
        await viewModel.loadTemplates(api: api)

        let firstSubmission = Task { await viewModel.submit(api: api) }
        await waitUntil { viewModel.isSubmitting }
        await viewModel.submit(api: api)
        await firstSubmission.value

        XCTAssertEqual(api.aiRetouchRequests.count, 1)
        XCTAssertFalse(viewModel.isSubmitting)
    }

    private func makeAPI() -> TravelAlbumMockAPI {
        let api = TravelAlbumMockAPI()
        api.aiRetouchTemplatesResponse = TravelAlbumAIRetouchTemplatesResponse(
            refinedTemplates: [template(11, "清透"), template(12, "自然")],
            atmosphereTemplates: [template(21, "暖阳")],
            coverTemplates: [template(31, "杂志")]
        )
        return api
    }

    private func template(_ id: Int, _ name: String) -> TravelAlbumAIRetouchTemplate {
        TravelAlbumAIRetouchTemplate(id: id, name: name, previewURL: "https://cdn.example.com/\(id).jpg")
    }

    private func waitUntil(_ condition: @escaping () -> Bool) async {
        for _ in 0 ..< 100 {
            if condition() { return }
            await Task.yield()
        }
    }
}