import Foundation
import Units

public struct Product: Codable, Sendable, Identifiable {
	public let code: String?
	public let productName: String?
	public let genericName: String?
	public let brands: String?
	public let brandsTags: [String]?
	public let quantity: String?

	// MARK: - Images
	public let imageFrontUrl: String?
	public let imageSmallUrl: String?
	public let imageUrl: String?
	public let imageNutritionSmallUrl: String?
	public let imageNutritionThumbUrl: String?
	public let imageNutritionUrl: String?
	public let imageIngredientsSmallUrl: String?
	public let imageIngredientsThumbUrl: String?
	public let imageIngredientsUrl: String?

	// MARK: - Quantities
	public let productQuantity: Float?
	public let productQuantityUnit: String?
	public let servingQuantity: String?
	public let servingQuantityUnit: String?
	public let servingSize: String?

	// MARK: - Grades & Scores
	public let nutriscoreGrade: String?
	public let nutriscoreData: NutriscoreData?
	public let novaGroup: Int?
	public let ecoscoreGrade: String?

	public let nutritionDataPer: String?
	public let nutriments: Nutriments?
	public let nutrientLevels: NutrientLevels?

	// MARK: - Ingredients & Allergens
	public let ingredientsText: String?
	public let ingredients: [Ingredient]?
	public let ingredientsHierarchy: [String]?
	public let allergens: String?
	public let allergensHierarchy: [String]?

	public let additivesN: Int?

	// MARK: - Metadata
	public let checked: String?
	public let complete: Int?
	public let completeness: Float?
	public var categories: String?
	public var categoriesHierarchy: [String]?

	public var id: String {
		guard let code = code else {
			return UUID().uuidString
		}
		return code
	}

	// MARK: - Computed Properties (Units)
	public var waterQuantity: Units.UnitValue<Double>? {
		guard let ingredient = ingredients?.first(where: { $0.isWater }) else {
			return nil
		}

		guard let quantity = productQuantity,
			let estimate = ingredient.percentEstimate,
			let rawUnit = productQuantityUnit,
			let unit = Units.Unit(rawValue: rawUnit)
		else {
			return nil
		}

		return Double(quantity * (estimate / 100))[unit]
	}

	public var isLiquid: Bool {
		guard let rawUnit = productQuantityUnit,
			let unit = Units.Unit(rawValue: rawUnit)
		else {
			return false
		}

		return unit.category == .volume
	}

	// MARK: - CodingKeys
	private enum CodingKeys: String, CodingKey {
		case code
		case productName = "product_name"
		case genericName = "generic_name"
		case brands
		case brandsTags = "brands_tags"
		case quantity

		// Images
		case imageFrontUrl = "image_front_url"
		case imageSmallUrl = "image_small_url"
		case imageUrl = "image_url"
		case imageNutritionSmallUrl = "image_nutrition_small_url"
		case imageNutritionThumbUrl = "image_nutrition_thumb_url"
		case imageNutritionUrl = "image_nutrition_url"
		case imageIngredientsSmallUrl = "image_ingredients_small_url"
		case imageIngredientsThumbUrl = "image_ingredients_thumb_url"
		case imageIngredientsUrl = "image_ingredients_url"

		// Quantities
		case productQuantity = "product_quantity"
		case productQuantityUnit = "product_quantity_unit"
		case servingQuantity = "serving_quantity"
		case servingQuantityUnit = "serving_quantity_unit"
		case servingSize = "serving_size"

		case ingredientsText = "ingredients_text"
		case ingredients
		case ingredientsHierarchy = "ingredients_hierarchy"

		// Grades & Data
		case nutriscoreGrade = "nutriscore_grade"
		case nutriscoreData = "nutriscore_data"
		case ecoscoreGrade = "ecoscore_grade"
		case novaGroup = "nova_group"
		case nutriments
		case nutrientLevels = "nutrient_levels"
		case nutritionDataPer = "nutrition_data_per"

		case complete
		case completeness
		case additivesN = "additives_n"
		case checked

		case allergens
		case allergensHierarchy = "allergens_hierarchy"
		case categories
		case categoriesHierarchy = "categories_hierarchy"
	}

	// MARK: - Initializer
	public init(from decoder: any Decoder) throws {
		let container = try decoder.container(keyedBy: CodingKeys.self)

		code = try container.decodeIfPresent(String.self, forKey: .code)
		productName = try container.decodeIfPresent(
			String.self, forKey: .productName)
		genericName = try container.decodeIfPresent(
			String.self, forKey: .genericName)
		brands = try container.decodeIfPresent(String.self, forKey: .brands)
		brandsTags = try container.decodeIfPresent(
			[String].self, forKey: .brandsTags)
		quantity = try container.decodeIfPresent(String.self, forKey: .quantity)

		// Images
		imageFrontUrl = try container.decodeIfPresent(
			String.self, forKey: .imageFrontUrl)
		imageSmallUrl = try container.decodeIfPresent(
			String.self, forKey: .imageSmallUrl)
		imageUrl = try container.decodeIfPresent(String.self, forKey: .imageUrl)
		imageNutritionSmallUrl = try container.decodeIfPresent(
			String.self, forKey: .imageNutritionSmallUrl)
		imageNutritionThumbUrl = try container.decodeIfPresent(
			String.self, forKey: .imageNutritionThumbUrl)
		imageNutritionUrl = try container.decodeIfPresent(
			String.self, forKey: .imageNutritionUrl)
		imageIngredientsSmallUrl = try container.decodeIfPresent(
			String.self, forKey: .imageIngredientsSmallUrl)
		imageIngredientsThumbUrl = try container.decodeIfPresent(
			String.self, forKey: .imageIngredientsThumbUrl)
		imageIngredientsUrl = try container.decodeIfPresent(
			String.self, forKey: .imageIngredientsUrl)

		// Quantities (Robust decoding)
		productQuantity = try container.decodeFloatOrString(
			forKey: .productQuantity)
		productQuantityUnit = try container.decodeIfPresent(
			String.self, forKey: .productQuantityUnit)

		// servingQuantity is String?, but API might return a number
		if let floatVal = try? container.decode(
			Float.self, forKey: .servingQuantity)
		{
			servingQuantity = String(floatVal)
		} else {
			servingQuantity = try container.decodeIfPresent(
				String.self, forKey: .servingQuantity)
		}

		servingQuantityUnit = try container.decodeIfPresent(
			String.self, forKey: .servingQuantityUnit)
		servingSize = try container.decodeIfPresent(
			String.self, forKey: .servingSize)

		// Ingredients & Categories
		ingredientsText = try container.decodeIfPresent(
			String.self, forKey: .ingredientsText)
		ingredients = try container.decodeIfPresent(
			[Ingredient].self, forKey: .ingredients)
		ingredientsHierarchy = try container.decodeIfPresent(
			[String].self, forKey: .ingredientsHierarchy)

		categories = try container.decodeIfPresent(
			String.self, forKey: .categories)
		categoriesHierarchy = try container.decodeIfPresent(
			[String].self, forKey: .categoriesHierarchy)

		// Grades & Nutriments
		nutriscoreGrade = try container.decodeIfPresent(
			String.self, forKey: .nutriscoreGrade)
		nutriscoreData = try container.decodeIfPresent(
			NutriscoreData.self, forKey: .nutriscoreData)
		novaGroup = try container.decodeIfPresent(Int.self, forKey: .novaGroup)
		ecoscoreGrade = try container.decodeIfPresent(
			String.self, forKey: .ecoscoreGrade)

		nutriments = try container.decodeIfPresent(
			Nutriments.self, forKey: .nutriments)
		nutrientLevels = try container.decodeIfPresent(
			NutrientLevels.self, forKey: .nutrientLevels)
		nutritionDataPer = try container.decodeIfPresent(
			String.self, forKey: .nutritionDataPer)

		// Misc
		additivesN = try container.decodeIfPresent(
			Int.self, forKey: .additivesN)
		checked = try container.decodeIfPresent(String.self, forKey: .checked)
		complete = try container.decodeIfPresent(Int.self, forKey: .complete)
		completeness = try container.decodeFloatOrString(forKey: .completeness)

		allergens = try container.decodeIfPresent(
			String.self, forKey: .allergens)
		allergensHierarchy = try container.decodeIfPresent(
			[String].self, forKey: .allergensHierarchy)
	}
}