//
//  Copyright RevenueCat Inc. All Rights Reserved.
//
//  Licensed under the MIT License (the "License");
//  you may not use this file except in compliance with the License.
//  You may obtain a copy of the License at
//
//      https://opensource.org/licenses/MIT
//
//  Codable+Extensions.swift
//
//  Created by Nacho Soto on 11/29/22.

import Foundation

extension Encodable {

    /// - Throws: if encoding failed
    /// - Returns: `nil` if the encoded `Data` can't be serialized into a `String`.
    var prettyPrintedJSON: String? {
        get throws {
            return String(data: try self.prettyPrintedData, encoding: .utf8)
        }
    }

    /// - Throws: if encoding failed
    /// - Returns: `nil` if the encoded `Data` can't be serialized into a `String`.
    var encodedJSON: String? {
        get throws {
            return String(data: try self.jsonEncodedData, encoding: .utf8)
        }
    }

    // MARK: -

    var prettyPrintedData: Data {
        get throws {
            return try JSONEncoder.prettyPrinted.encode(self)
        }
    }

    /// - Note: beginning with iOS 17, the output of this is not guaranteed to be consistent due to key ordering.
    /// For tests, it's better to compare `prettyPrintedData` which does sort keys.
    var jsonEncodedData: Data {
        get throws {
            return try JSONEncoder.default.encode(self)
        }
    }

}

extension JSONEncoder {

    static let `default`: JSONEncoder = {
        let encoder = JSONEncoder()
        encoder.keyEncodingStrategy = .convertToSnakeCase
        encoder.dateEncodingStrategy = .iso8601

        return encoder
    }()

    /// JSONEncoder with sorted keys (compact format)
    static let sortedKeys: JSONEncoder = {
        let encoder = JSONEncoder()
        encoder.keyEncodingStrategy = .convertToSnakeCase
        encoder.dateEncodingStrategy = .iso8601
        encoder.outputFormatting = [.sortedKeys]

        return encoder
    }()

    /// JSONEncoder (just like the default one, but prettyPrinted and sortedKeys)
    static let prettyPrinted: JSONEncoder = {
        let encoder = JSONEncoder()
        encoder.keyEncodingStrategy = .convertToSnakeCase
        encoder.dateEncodingStrategy = .iso8601
        encoder.outputFormatting = [.sortedKeys, .prettyPrinted]

        return encoder
    }()

}

extension JSONDecoder {

    static let iso8601WithFractionalSeconds: ISO8601DateFormatter = {
        let formatter = ISO8601DateFormatter()
        formatter.formatOptions = [.withInternetDateTime, .withFractionalSeconds]
        return formatter
    }()

    static let iso8601WithoutFractionalSeconds: ISO8601DateFormatter = {
        let formatter = ISO8601DateFormatter()
        formatter.formatOptions = [.withInternetDateTime]
        return formatter
    }()

    static let `default`: JSONDecoder = {
        let decoder = JSONDecoder()
        decoder.keyDecodingStrategy = .convertFromSnakeCase
        decoder.dateDecodingStrategy = .custom { decoder in
            let container = try decoder.singleValueContainer()
            let raw = try container.decode(String.self)

            if let date = iso8601WithFractionalSeconds.date(from: raw) {
                return date
            }

            if let date = iso8601WithoutFractionalSeconds.date(from: raw) {
                return date
            }

            throw DecodingError.dataCorruptedError(in: container, debugDescription: "Invalid ISO8601 date: \(raw)")
        }

        return decoder
    }()

}