// --------------------------------------------------------------------------
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// The MIT License (MIT)
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import AzureCommunicationCommon
import AzureCore
import Foundation
import Trouter

func decode(jwtToken jwt: String) throws -> [String: Any] {
    enum DecodeErrors: Error {
        case badToken
        case other
    }

    func base64Decode(_ base64: String) throws -> Data {
        let base64 = base64
            .replacingOccurrences(of: "-", with: "+")
            .replacingOccurrences(of: "_", with: "/")
        let padded = base64.padding(toLength: ((base64.count + 3) / 4) * 4, withPad: "=", startingAt: 0)
        guard let decoded = Data(base64Encoded: padded) else {
            throw DecodeErrors.badToken
        }
        return decoded
    }

    func decodeJWTPart(_ value: String) throws -> [String: Any] {
        let bodyData = try base64Decode(value)
        let json = try JSONSerialization.jsonObject(with: bodyData, options: [])
        guard let payload = json as? [String: Any] else {
            throw DecodeErrors.other
        }
        return payload
    }

    let segments = jwt.components(separatedBy: ".")
    return try decodeJWTPart(segments[1])
}

func isDod(id: String) -> Bool {
    let gcchTeamsUserPrefix = "dod:"
    let gcchAcsUserPrefix = "dod-acs:"
    return (id.starts(with: gcchTeamsUserPrefix) || id.starts(with: gcchAcsUserPrefix))
}

func isGcch(id: String) -> Bool {
    let gcchTeamsUserPrefix = "gcch:"
    let gcchAcsUserPrefix = "gcch-acs:"
    return (id.starts(with: gcchTeamsUserPrefix) || id.starts(with: gcchAcsUserPrefix))
}
