//
//  MoodLoggerIntegrationTests.swift
//  Tests iOS
//
//  Pipeline 10: Side Effects Orchestration
//  Pipeline 11: Full Pipeline Integration
//

import XCTest
@testable import Feels

@MainActor
final class MoodLoggerIntegrationTests: XCTestCase {

    // MARK: - Helpers

    private func date(daysAgo: Int) -> Date {
        Calendar.current.date(byAdding: .day, value: -daysAgo, to: Calendar.current.startOfDay(for: Date()))!
            .addingTimeInterval(12 * 3600)
    }

    // MARK: - Setup / Teardown

    override func setUp() async throws {
        try await super.setUp()
        await MainActor.run {
            DataController.shared.clearDB()
        }
    }

    override func tearDown() async throws {
        await MainActor.run {
            DataController.shared.clearDB()
        }
        try await super.tearDown()
    }

    // MARK: - Pipeline 10: Side Effects Orchestration

    /// Verify that logMood creates an entry with the correct mood value.
    func testLogMood_CreatesEntry() {
        let targetDate = date(daysAgo: 0)

        MoodLogger.shared.logMood(.great, for: targetDate, entryType: .listView)

        let entry = DataController.shared.getEntry(byDate: targetDate)
        XCTAssertNotNil(entry, "Entry should exist after logMood")
        XCTAssertEqual(entry?.mood, .great, "Entry mood should be .great")
        XCTAssertEqual(entry?.entryType, EntryType.listView.rawValue, "Entry type should be listView")
    }

    /// Verify that logMood with .missing still creates the entry (DataController.add runs)
    /// but the side-effects path is skipped (applySideEffects guards against .missing).
    func testLogMood_SkipsSideEffectsForMissing() {
        let targetDate = date(daysAgo: 1)

        MoodLogger.shared.logMood(.missing, for: targetDate, entryType: .filledInMissing)

        let entry = DataController.shared.getEntry(byDate: targetDate)
        XCTAssertNotNil(entry, "Entry should be created even for .missing mood")
        XCTAssertEqual(entry?.mood, .missing, "Entry mood should be .missing")
    }

    /// Verify that logMood with syncHealthKit=false still creates the entry correctly
    /// and does not crash (we cannot verify HealthKit was NOT called without mocks).
    func testLogMood_WithDisabledHealthKit() {
        let targetDate = date(daysAgo: 2)

        MoodLogger.shared.logMood(.good, for: targetDate, entryType: .widget, syncHealthKit: false)

        let entry = DataController.shared.getEntry(byDate: targetDate)
        XCTAssertNotNil(entry, "Entry should be created with syncHealthKit=false")
        XCTAssertEqual(entry?.mood, .good, "Mood should be .good")
        XCTAssertEqual(entry?.entryType, EntryType.widget.rawValue, "Entry type should be widget")
    }

    /// Verify that updateMood returns true and updates the mood value when the entry exists.
    func testUpdateMood_ReturnsTrue() {
        let targetDate = date(daysAgo: 0)

        // Create initial entry
        MoodLogger.shared.logMood(.average, for: targetDate, entryType: .listView)
        let entryBefore = DataController.shared.getEntry(byDate: targetDate)
        XCTAssertEqual(entryBefore?.mood, .average, "Initial mood should be .average")

        // Update the mood
        let result = MoodLogger.shared.updateMood(entryDate: targetDate, withMood: .great)
        XCTAssertTrue(result, "updateMood should return true for an existing entry")

        let entryAfter = DataController.shared.getEntry(byDate: targetDate)
        XCTAssertEqual(entryAfter?.mood, .great, "Updated mood should be .great")
    }

    /// Verify that updateMood returns false for a date with no existing entry.
    func testUpdateMood_NonexistentDate_ReturnsFalse() {
        let emptyDate = date(daysAgo: 100) // far in the past, no entry

        let result = MoodLogger.shared.updateMood(entryDate: emptyDate, withMood: .good)
        XCTAssertFalse(result, "updateMood should return false when no entry exists")
    }

    /// Verify that deleteMood replaces the entry with a .missing mood and .filledInMissing type.
    func testDeleteMood_ReplacesWithMissing() {
        let targetDate = date(daysAgo: 1)

        // Create an entry
        MoodLogger.shared.logMood(.good, for: targetDate, entryType: .listView)
        let entryBefore = DataController.shared.getEntry(byDate: targetDate)
        XCTAssertEqual(entryBefore?.mood, .good, "Entry should be .good before delete")

        // Delete the mood
        MoodLogger.shared.deleteMood(forDate: targetDate)

        let entryAfter = DataController.shared.getEntry(byDate: targetDate)
        XCTAssertNotNil(entryAfter, "Entry should still exist after delete (replaced with .missing)")
        XCTAssertEqual(entryAfter?.mood, .missing, "Mood should be .missing after delete")
        XCTAssertEqual(entryAfter?.entryType, EntryType.filledInMissing.rawValue, "Entry type should be .filledInMissing after delete")
    }

    /// Verify that deleteAllData removes all entries from the database.
    func testDeleteAllData_ClearsEverything() {
        // Add 5 entries on consecutive days
        for i in 0..<5 {
            MoodLogger.shared.logMood(.good, for: date(daysAgo: i), entryType: .listView)
        }

        // Verify entries exist
        for i in 0..<5 {
            let entry = DataController.shared.getEntry(byDate: date(daysAgo: i))
            XCTAssertNotNil(entry, "Entry should exist for day \(i) before deleteAllData")
        }

        // Delete all data
        MoodLogger.shared.deleteAllData()

        // Verify all entries are gone
        for i in 0..<5 {
            let entry = DataController.shared.getEntry(byDate: date(daysAgo: i))
            XCTAssertNil(entry, "Entry should be nil for day \(i) after deleteAllData")
        }
    }

    // MARK: - Pipeline 11: Full Pipeline Integration

    /// Log consecutive moods and verify the streak increases with each day.
    func testPipeline_LogVote_StreakIncreases() {
        let day2 = date(daysAgo: 2)
        let day1 = date(daysAgo: 1)
        let day0 = date(daysAgo: 0)

        // Log day 2 (2 days ago)
        MoodLogger.shared.logMood(.good, for: day2, entryType: .listView)
        let streak1 = DataController.shared.calculateStreak(from: day2)
        XCTAssertEqual(streak1.streak, 1, "Streak from day 2 with only day 2 logged should be 1")

        // Log day 1 (1 day ago)
        MoodLogger.shared.logMood(.great, for: day1, entryType: .listView)
        let streak2 = DataController.shared.calculateStreak(from: day1)
        XCTAssertEqual(streak2.streak, 2, "Streak from day 1 with days 1-2 logged should be 2")

        // Log day 0 (today)
        MoodLogger.shared.logMood(.average, for: day0, entryType: .listView)
        let streak3 = DataController.shared.calculateStreak(from: day0)
        XCTAssertEqual(streak3.streak, 3, "Streak from day 0 with days 0-2 logged should be 3")
    }

    /// Log 3 consecutive moods, delete the middle one, verify streak breaks.
    func testPipeline_DeleteBreaksStreak() {
        let day0 = date(daysAgo: 0)
        let day1 = date(daysAgo: 1)
        let day2 = date(daysAgo: 2)

        // Log moods for 3 consecutive days
        MoodLogger.shared.logMood(.good, for: day0, entryType: .listView)
        MoodLogger.shared.logMood(.great, for: day1, entryType: .listView)
        MoodLogger.shared.logMood(.average, for: day2, entryType: .listView)

        let streakBefore = DataController.shared.calculateStreak(from: day0)
        XCTAssertEqual(streakBefore.streak, 3, "Streak from day 0 with 3 consecutive days should be 3")

        // Delete the middle day (day 1)
        MoodLogger.shared.deleteMood(forDate: day1)

        let streakAfter = DataController.shared.calculateStreak(from: day0)
        XCTAssertEqual(streakAfter.streak, 1, "Streak from day 0 after deleting day 1 should be 1 (only day 0 contiguous)")
    }

    /// Log moods with a gap, fill the gap, verify streak rebuilds.
    func testPipeline_LogPastDate_RebuildsStreak() {
        let day0 = date(daysAgo: 0)
        let day1 = date(daysAgo: 1)
        let day2 = date(daysAgo: 2)

        // Log days 0 and 2 (skip day 1)
        MoodLogger.shared.logMood(.good, for: day0, entryType: .listView)
        MoodLogger.shared.logMood(.average, for: day2, entryType: .listView)

        let streakGap = DataController.shared.calculateStreak(from: day0)
        XCTAssertEqual(streakGap.streak, 1, "Streak from day 0 with gap at day 1 should be 1")

        // Fill the gap by logging day 1
        MoodLogger.shared.logMood(.great, for: day1, entryType: .listView)

        let streakFilled = DataController.shared.calculateStreak(from: day0)
        XCTAssertEqual(streakFilled.streak, 3, "Streak from day 0 after filling gap should be 3")
    }

    /// Log 3 consecutive moods, delete the oldest, verify current streak changes but recent entry is intact.
    func testPipeline_DeleteOlderDay_CurrentStreakUnchanged() {
        let day0 = date(daysAgo: 0)
        let day1 = date(daysAgo: 1)
        let day2 = date(daysAgo: 2)

        // Log moods for 3 consecutive days
        MoodLogger.shared.logMood(.great, for: day0, entryType: .listView)
        MoodLogger.shared.logMood(.good, for: day1, entryType: .listView)
        MoodLogger.shared.logMood(.average, for: day2, entryType: .listView)

        let streakBefore = DataController.shared.calculateStreak(from: day0)
        XCTAssertEqual(streakBefore.streak, 3, "Streak from day 0 with 3 consecutive days should be 3")

        // Delete the oldest day (day 2)
        MoodLogger.shared.deleteMood(forDate: day2)

        let streakAfter = DataController.shared.calculateStreak(from: day0)
        XCTAssertEqual(streakAfter.streak, 2, "Streak from day 0 after deleting day 2 should be 2 (days 0 and 1 still contiguous)")

        // Verify day 0 entry is still intact
        let entry = DataController.shared.getEntry(byDate: day0)
        XCTAssertNotNil(entry, "Day 0 entry should still exist")
        XCTAssertEqual(entry?.mood, .great, "Day 0 mood should still be .great")
    }

    /// Full voting date and missing vote lifecycle:
    /// OnboardingData with .Today and time 00:00 means voting is always "passed"
    /// so getCurrentVotingDate returns the `now` date itself.
    func testPipeline_VotingDateAndMissingVote() {
        let calendar = Calendar.current

        // 1. Create OnboardingData with .Today and time at 00:00 (always passed)
        let onboarding = OnboardingData()
        onboarding.inputDay = .Today
        onboarding.date = calendar.startOfDay(for: Date()) // hour 0, minute 0

        // 2. Set `now` to today at noon
        let todayNoon = calendar.startOfDay(for: Date()).addingTimeInterval(12 * 3600)

        // 3. Get voting date -- should be `now` (today) since time is passed and inputDay is .Today
        let votingDate = ShowBasedOnVoteLogics.getCurrentVotingDate(onboardingData: onboarding, now: todayNoon)
        XCTAssertTrue(
            calendar.isDate(votingDate, inSameDayAs: todayNoon),
            "Voting date should be the same day as `now` when inputDay=.Today and time has passed"
        )

        // 4. isMissingCurrentVote should be true (no entry yet)
        let missingBefore = ShowBasedOnVoteLogics.isMissingCurrentVote(onboardingData: onboarding, now: todayNoon)
        XCTAssertTrue(missingBefore, "Should be missing current vote before logging")

        // 5. Log mood for the voting date
        MoodLogger.shared.logMood(.good, for: votingDate, entryType: .listView)

        // 6. isMissingCurrentVote with same `now` should be false
        let missingAfter = ShowBasedOnVoteLogics.isMissingCurrentVote(onboardingData: onboarding, now: todayNoon)
        XCTAssertFalse(missingAfter, "Should NOT be missing current vote after logging")

        // 7. Move `now` forward by 1 day
        let tomorrowNoon = todayNoon.addingTimeInterval(24 * 3600)

        // 8. isMissingCurrentVote should be true again (new day, no entry)
        let missingNextDay = ShowBasedOnVoteLogics.isMissingCurrentVote(onboardingData: onboarding, now: tomorrowNoon)
        XCTAssertTrue(missingNextDay, "Should be missing vote for the next day")

        // 9. Log mood for the new voting date
        let newVotingDate = ShowBasedOnVoteLogics.getCurrentVotingDate(onboardingData: onboarding, now: tomorrowNoon)
        MoodLogger.shared.logMood(.great, for: newVotingDate, entryType: .listView)

        // 10. Calculate streak from the new voting date -- should be 2 (two consecutive days)
        let streak = DataController.shared.calculateStreak(from: newVotingDate)
        XCTAssertEqual(streak.streak, 2, "Streak should be 2 after logging moods on two consecutive days")
        XCTAssertEqual(streak.todaysMood, .great, "Today's mood should be .great")
    }
}