import Foundation
import Testing
@testable import bookstax

// MARK: - Recent Searches

@Suite("SearchViewModel – Recent Searches", .serialized)
struct SearchViewModelRecentTests {

    private let recentKey = "recentSearches"

    init() {
        // Start each test with a clean slate
        UserDefaults.standard.removeObject(forKey: recentKey)
    }

    // MARK: addToRecent

    @Test("Adding a query inserts it at position 0")
    func addInsertsAtFront() {
        let vm = SearchViewModel()
        vm.addToRecent("swift")
        vm.addToRecent("swiftui")
        let recent = vm.recentSearches
        #expect(recent.first == "swiftui")
        #expect(recent[1] == "swift")
    }

    @Test("Adding duplicate moves it to front without creating duplicates")
    func addDeduplicates() {
        let vm = SearchViewModel()
        vm.addToRecent("bookstack")
        vm.addToRecent("wiki")
        vm.addToRecent("bookstack") // duplicate
        let recent = vm.recentSearches
        #expect(recent.first == "bookstack")
        #expect(recent.count == 2)
        #expect(!recent.dropFirst().contains("bookstack"))
    }

    @Test("List is capped at 10 entries")
    func cappedAtTen() {
        let vm = SearchViewModel()
        for i in 1...12 {
            vm.addToRecent("query\(i)")
        }
        #expect(vm.recentSearches.count == 10)
    }

    @Test("Oldest entries are dropped when cap is exceeded")
    func oldestDropped() {
        let vm = SearchViewModel()
        for i in 1...11 {
            vm.addToRecent("query\(i)")
        }
        let recent = vm.recentSearches
        // query1 was added first, so it falls off after 11 adds
        #expect(!recent.contains("query1"))
        #expect(recent.contains("query11"))
    }

    // MARK: clearRecentSearches

    @Test("clearRecentSearches empties the list")
    func clearResetsToEmpty() {
        let vm = SearchViewModel()
        vm.addToRecent("something")
        vm.clearRecentSearches()
        #expect(vm.recentSearches.isEmpty)
    }

    // MARK: Persistence

    @Test("Recent searches persist across ViewModel instances")
    func persistsAcrossInstances() {
        let vm1 = SearchViewModel()
        vm1.addToRecent("persistent")

        let vm2 = SearchViewModel()
        #expect(vm2.recentSearches.contains("persistent"))
    }
}

// MARK: - Query Minimum Length

@Suite("SearchViewModel – Query Logic")
struct SearchViewModelQueryTests {

    @Test("Short query clears results without triggering search")
    func shortQueryClearsResults() {
        let vm = SearchViewModel()
        vm.results = [SearchResultDTO(id: 1, name: "dummy", slug: "dummy",
                                      type: .page, url: "", preview: nil)]
        vm.query = "x" // only 1 character
        vm.onQueryChanged()
        #expect(vm.results.isEmpty)
    }

    @Test("Query with 2+ chars does not clear results immediately")
    func sufficientQueryKeepsResults() {
        let vm = SearchViewModel()
        vm.query = "sw" // 2 characters — triggers debounce but does not clear
        vm.onQueryChanged()
        // Results not cleared by onQueryChanged when query is long enough
        // (actual search would require API; here we just verify results aren't wiped)
        // Results were empty to start with, so we just confirm no crash
        #expect(vm.results.isEmpty) // no API call, so still empty
    }
}