//
//  GuidedReflection.swift
//  Reflect
//
//  Codable model for guided reflection responses, stored as JSON in MoodEntryModel.
//

import Foundation

// MARK: - Mood Category

enum MoodCategory: String, Codable {
    case positive  // great, good → 3 questions (Behavioral Activation)
    case neutral   // average → 4 questions (ACT Cognitive Defusion)
    case negative  // bad, horrible → 4 questions (CBT Thought Record)

    init(from mood: Mood) {
        switch mood {
        case .great, .good: self = .positive
        case .average: self = .neutral
        case .horrible, .bad: self = .negative
        default: self = .neutral
        }
    }

    var questionCount: Int {
        switch self {
        case .positive: return 3
        case .neutral, .negative: return 4
        }
    }

    /// The therapeutic technique name for display purposes.
    var techniqueName: String {
        switch self {
        case .positive: return "Behavioral Activation"
        case .neutral: return "Acceptance & Commitment Therapy"
        case .negative: return "Cognitive Behavioral Therapy"
        }
    }

    /// Short CBT step labels shown above each question.
    var stepLabels: [String] {
        switch self {
        case .negative:
            return [
                String(localized: "Situation"),
                String(localized: "Automatic Thought"),
                String(localized: "Perspective Check"),
                String(localized: "Reframe"),
            ]
        case .neutral:
            return [
                String(localized: "Awareness"),
                String(localized: "Thought"),
                String(localized: "Defusion"),
                String(localized: "Values"),
            ]
        case .positive:
            return [
                String(localized: "Activity"),
                String(localized: "Awareness"),
                String(localized: "Planning"),
            ]
        }
    }
}

// MARK: - Guided Reflection

struct GuidedReflection: Codable, Equatable {

    struct Response: Codable, Equatable, Identifiable {
        var id: Int  // question index (0-based)
        let question: String
        var answer: String
    }

    let moodCategory: MoodCategory
    var responses: [Response]
    var completedAt: Date?

    // MARK: - Computed Properties

    var isComplete: Bool {
        responses.count == moodCategory.questionCount &&
        responses.allSatisfy { !$0.answer.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty }
    }

    var answeredCount: Int {
        responses.filter { !$0.answer.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty }.count
    }

    var totalQuestions: Int {
        moodCategory.questionCount
    }

    // MARK: - Factory

    static func createNew(for mood: Mood) -> GuidedReflection {
        let category = MoodCategory(from: mood)
        let questionTexts = questions(for: category)
        let responses = questionTexts.enumerated().map { index, question in
            Response(id: index, question: question, answer: "")
        }
        return GuidedReflection(moodCategory: category, responses: responses, completedAt: nil)
    }

    static func questions(for category: MoodCategory) -> [String] {
        switch category {
        case .positive:
            return [
                String(localized: "guided_reflection_positive_q1"),
                String(localized: "guided_reflection_positive_q2"),
                String(localized: "guided_reflection_positive_q3"),
            ]
        case .neutral:
            return [
                String(localized: "guided_reflection_neutral_q1"),
                String(localized: "guided_reflection_neutral_q2"),
                String(localized: "guided_reflection_neutral_q3"),
                String(localized: "guided_reflection_neutral_q4"),
            ]
        case .negative:
            return [
                String(localized: "guided_reflection_negative_q1"),
                String(localized: "guided_reflection_negative_q2"),
                String(localized: "guided_reflection_negative_q3"),
                String(localized: "guided_reflection_negative_q4"),
            ]
        }
    }

    // MARK: - JSON Helpers

    func encode() -> String? {
        guard let data = try? JSONEncoder().encode(self) else { return nil }
        return String(data: data, encoding: .utf8)
    }

    static func decode(from json: String) -> GuidedReflection? {
        guard let data = json.data(using: .utf8) else { return nil }
        return try? JSONDecoder().decode(GuidedReflection.self, from: data)
    }
}