import Foundation
import CallKit

class CallDirectoryHandler: CXCallDirectoryProvider {

    override func beginRequest(with context: CXCallDirectoryExtensionContext) {
        context.delegate = self

        do {
            try addBlockingPhoneNumbers(to: context)
        } catch {
            NSLog("Unable to add blocking phone numbers")
            let error = NSError(domain: "CallDirectoryHandler", code: 1, userInfo: nil)
            context.cancelRequest(withError: error)
            return
        }

        do {
            try addIdentificationPhoneNumbers(to: context)
        } catch {
            NSLog("Unable to add identification phone numbers")
            let error = NSError(domain: "CallDirectoryHandler", code: 2, userInfo: nil)
            context.cancelRequest(withError: error)
            return
        }

        context.completeRequest()
    }

    private func addBlockingPhoneNumbers(to context: CXCallDirectoryExtensionContext) throws {
        // Retrieve phone numbers to block from data store. For optimal performance and memory usage when there are many phone numbers,
        // consider only loading a subset of numbers at a given time and using autorelease pool(s) to release objects allocated during each batch of numbers which are loaded.
        //
        // Numbers must be provided in numerically ascending order.
        let phoneNumbers: [CXCallDirectoryPhoneNumber] = [ 14085555555, 18005555555 ]

        for phoneNumber in phoneNumbers {
            context.addBlockingEntry(withNextSequentialPhoneNumber: phoneNumber)
        }
    }

    private func addIdentificationPhoneNumbers(to context: CXCallDirectoryExtensionContext) throws {
        guard let fileUrl = FileManager.default
            .containerURL(forSecurityApplicationGroupIdentifier: "group.ru.touchin.TouchInApp")?
            .appendingPathComponent("contacts") else { return }
        
        guard let reader = LineReader(path: fileUrl.path) else { return }
        
        for line in reader {
            autoreleasepool {
                // считываем строку и удаляем перевод строки в конце
                let line = line.trimmingCharacters(in: .whitespacesAndNewlines)
                
                // отделяем номер от имени
                var components = line.components(separatedBy: ",")
                
                // приводим номер к Int64
                guard let phone = Int64(components[0]) else { return }
                let name = components[1]
                
                context.addIdentificationEntry(withNextSequentialPhoneNumber: phone, label: name)
            }
        }
    }

}

extension CallDirectoryHandler: CXCallDirectoryExtensionContextDelegate {

    func requestFailed(for extensionContext: CXCallDirectoryExtensionContext, withError error: Error) {
        // An error occurred while adding blocking or identification entries, check the NSError for details.
        // For Call Directory error codes, see the CXErrorCodeCallDirectoryManagerError enum in <CallKit/CXError.h>.
        //
        // This may be used to store the error details in a location accessible by the extension's containing app, so that the
        // app may be notified about errors which occured while loading data even if the request to load data was initiated by
        // the user in Settings instead of via the app itself.
    }

}