ios/chrome/browser/variations/ios_chrome_variations_seed_fetcher.h

// Copyright 2022 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef IOS_CHROME_BROWSER_VARIATIONS_IOS_CHROME_VARIATIONS_SEED_FETCHER_H_
#define IOS_CHROME_BROWSER_VARIATIONS_IOS_CHROME_VARIATIONS_SEED_FETCHER_H_

#import <Foundation/Foundation.h>

// Enum for the seed fetch result histogram. Must stay in sync with
// `VariationsSeedFetchResult` from enums.xml.
enum class IOSSeedFetchException : int {
  // Default value. DO NOT LOG.
  kNotApplicable = 0,
  // HTTPS request times out.
  kHTTPSRequestTimeout = -2,
  // Variations URL error.
  kHTTPSRequestBadUrl = -3,
  // The "IM" header returned from the variations server does not exist or
  // contains invalid value.
  kInvalidIMHeader = -5,
};

// Protocol for variations seed fetcher that reacts to variations seed fetch
// stages.
@protocol IOSChromeVariationsSeedFetcherDelegate

// Informs the delegate that the initial seed fetch has successfully completed
// or failed.
- (void)didFetchSeedSuccess:(BOOL)succeeded;

@end

// An object that allows its owner to fetch variations seed before Chrome
// components are initialized.
@interface IOSChromeVariationsSeedFetcher : NSObject

// Delegate object that observes the status of seed fetching.
@property(nonatomic, weak) id<IOSChromeVariationsSeedFetcherDelegate> delegate;

// Starts fetching the initial seed from the variations server.
//
// Note: the caller is responsible for making sure that a seed fetcher object is
// only be initiated when there is no valid variations seed available in local
// storage. In cases when this method is invoked when a variations seed is
// available, the downloaded seed would be disregarded.
- (void)startSeedFetch;

@end

#endif  // IOS_CHROME_BROWSER_VARIATIONS_IOS_CHROME_VARIATIONS_SEED_FETCHER_H_