//
//  MealPlanModels.swift
//  Nextcloud Cookbook iOS Client
//

import Foundation

/// Tracks meal plan assignments for a recipe, stored as `_mealPlanAssignment` in the recipe JSON on the server.
struct MealPlanAssignment: Codable {
    var version: Int = 1
    var lastModified: String
    var dates: [String: MealPlanDateEntry]

    init(lastModified: String = MealPlanDate.now(), dates: [String: MealPlanDateEntry] = [:]) {
        self.version = 1
        self.lastModified = lastModified
        self.dates = dates
    }
}

struct MealPlanDateEntry: Codable {
    enum Status: String, Codable {
        case assigned
        case removed
    }

    var status: Status
    var mealType: String?
    var modifiedAt: String

    init(status: Status, mealType: String? = nil, modifiedAt: String = MealPlanDate.now()) {
        self.status = status
        self.mealType = mealType
        self.modifiedAt = modifiedAt
    }
}

/// ISO 8601 date helpers for meal plan dates.
enum MealPlanDate {
    private static let isoFormatter: ISO8601DateFormatter = {
        let f = ISO8601DateFormatter()
        f.formatOptions = [.withInternetDateTime]
        return f
    }()

    private static let dayFormatter: DateFormatter = {
        let f = DateFormatter()
        f.dateFormat = "yyyy-MM-dd"
        f.timeZone = .current
        return f
    }()

    static func now() -> String {
        isoFormatter.string(from: Date())
    }

    static func date(from string: String) -> Date? {
        isoFormatter.date(from: string)
    }

    static func string(from date: Date) -> String {
        isoFormatter.string(from: date)
    }

    static func dayString(from date: Date) -> String {
        dayFormatter.string(from: date)
    }

    static func dateFromDay(_ dayString: String) -> Date? {
        dayFormatter.date(from: dayString)
    }
}

/// Local-only aggregated view struct used by the UI.
struct MealPlanEntry: Identifiable {
    let recipeId: String
    let recipeName: String
    let date: Date
    let dateString: String
    let mealType: String?

    var id: String { "\(recipeId)-\(dateString)" }
}