#import <XCTest/XCTest.h>

@import WMF;

@interface TWNStringsTests : XCTestCase

@property (class, strong, nonatomic, readonly) NSArray *bundledLprojFiles;
@property (class, strong, nonatomic, readonly) NSArray *iOSLprojFiles;
@property (class, strong, nonatomic, readonly) NSArray *twnLprojFiles;
@property (class, strong, nonatomic, readonly) NSString *bundleRoot;
@property (class, strong, nonatomic, readonly) NSArray *twnInfoPlistFilePaths;
@property (class, strong, nonatomic, readonly) NSArray *iOSInfoPlistFilePaths;
@property (class, strong, nonatomic, readonly) NSString *twnLocalizationsDirectory;
@property (class, strong, nonatomic, readonly) NSString *iOSLocalizationsDirectory;

@end

@implementation TWNStringsTests

- (void)setUp {
    [super setUp];
}

+ (NSString *)iOSLocalizationsDirectory {
    return [SOURCE_ROOT_DIR stringByAppendingPathComponent:@"Wikipedia/iOS Native Localizations"];
}

+ (NSString *)twnLocalizationsDirectory {
    return [SOURCE_ROOT_DIR stringByAppendingPathComponent:@"Wikipedia/Localizations"];
}

+ (NSString *)bundleRoot {
    return [[NSBundle wmf_localizationBundle] bundlePath];
}

+ (NSString *)appBundleRoot {
    return [[NSBundle mainBundle] bundlePath];
}

+ (NSArray *)bundledLprojFiles {
    static dispatch_once_t onceToken;
    static NSArray *bundledLprojFiles;
    dispatch_once(&onceToken, ^{
        bundledLprojFiles = [[[[NSFileManager defaultManager] contentsOfDirectoryAtPath:TWNStringsTests.bundleRoot error:nil] filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"pathExtension='lproj'"]] valueForKey:@"lowercaseString"];
    });
    return bundledLprojFiles;
}

+ (NSArray *)twnInfoPlistFilePaths {
    static dispatch_once_t onceToken;
    static NSArray *twnInfoPlistFilePaths;
    dispatch_once(&onceToken, ^{
        twnInfoPlistFilePaths = [self.twnLprojFiles wmf_map:^NSString *(NSString *lprojFileName) {
            return [[self.twnLocalizationsDirectory stringByAppendingPathComponent:lprojFileName] stringByAppendingPathComponent:@"InfoPlist.strings"];
        }];
    });
    return twnInfoPlistFilePaths;
}

+ (NSArray *)iOSInfoPlistFilePaths {
    static dispatch_once_t onceToken;
    static NSArray *infoPlistFilePaths;
    dispatch_once(&onceToken, ^{
        infoPlistFilePaths = [self.iOSLprojFiles wmf_map:^NSString *(NSString *lprojFileName) {
            return [[self.iOSLocalizationsDirectory stringByAppendingPathComponent:lprojFileName] stringByAppendingPathComponent:@"InfoPlist.strings"];
        }];
    });
    return infoPlistFilePaths;
}

+ (NSArray *)twnLprojFiles {
    static dispatch_once_t onceToken;
    static NSArray *twnLprojFiles;
    dispatch_once(&onceToken, ^{
        twnLprojFiles = [[[[NSFileManager defaultManager] contentsOfDirectoryAtPath:self.twnLocalizationsDirectory error:nil] filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"pathExtension='lproj'"]] valueForKey:@"lowercaseString"];
    });
    return twnLprojFiles;
}

+ (NSArray *)iOSLprojFiles {
    static dispatch_once_t onceToken;
    static NSArray *iOSLprojFiles;
    dispatch_once(&onceToken, ^{
        iOSLprojFiles = [[[[NSFileManager defaultManager] contentsOfDirectoryAtPath:self.iOSLocalizationsDirectory error:nil] filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"pathExtension='lproj'"]] valueForKey:@"lowercaseString"];
    });
    return iOSLprojFiles;
}

- (NSDictionary *)getPluralizableStringsDictFromLprogAtPath:(NSString *)lprojPath {
    NSString *stringsFilePath = [lprojPath stringByAppendingPathComponent:@"Localizable.stringsdict"];
    return [self getDictFromPListAtPath:stringsFilePath];
}

- (NSDictionary *)getTranslationStringsDictFromLprogAtPath:(NSString *)lprojPath {
    NSString *stringsFilePath = [lprojPath stringByAppendingPathComponent:@"Localizable.strings"];
    return [self getDictFromPListAtPath:stringsFilePath];
}

- (NSDictionary *)getDictFromPListAtPath:(NSString *)path {
    BOOL isDirectory = NO;
    if ([[NSFileManager defaultManager] fileExistsAtPath:path isDirectory:&isDirectory]) {
        return [NSDictionary dictionaryWithContentsOfFile:path];
    }
    return nil;
}

- (void)testLprojCount {
    XCTAssert(TWNStringsTests.iOSLprojFiles.count > 0);
    XCTAssert(TWNStringsTests.twnLprojFiles.count > 0);
}

+ (NSRegularExpression *)reverseiOSTokenRegex {
    static dispatch_once_t onceToken;
    static NSRegularExpression *reverseiOSTokenRegex;
    dispatch_once(&onceToken, ^{
        reverseiOSTokenRegex = [NSRegularExpression regularExpressionWithPattern:@"(:?[^%%])(:?[0-9]+)(?:[$])(:?[^@dDuUxXoOfeEgGcCsSpaAF])" options:0 error:nil];
    });
    return reverseiOSTokenRegex;
}

+ (NSRegularExpression *)reverseTWNTokenRegex {
    static dispatch_once_t onceToken;
    static NSRegularExpression *reverseTWNTokenRegex;
    dispatch_once(&onceToken, ^{
        reverseTWNTokenRegex = [NSRegularExpression regularExpressionWithPattern:@"(:?[0-9])(?:[$])(:?[^0-9])" options:0 error:nil];
    });
    return reverseTWNTokenRegex;
}

+ (NSRegularExpression *)twnTokenRegex {
    static dispatch_once_t onceToken;
    static NSRegularExpression *twnTokenRegex;
    dispatch_once(&onceToken, ^{
        twnTokenRegex = [NSRegularExpression regularExpressionWithPattern:@"(?:[$])(:?[0-9]+)" options:0 error:nil];
    });
    return twnTokenRegex;
}

+ (NSRegularExpression *)percentNumberRegex {
    static dispatch_once_t onceToken;
    static NSRegularExpression *percentNumberRegex;
    dispatch_once(&onceToken, ^{
        percentNumberRegex = [NSRegularExpression regularExpressionWithPattern:@"(?:[%%])(:?[0-9s])" options:0 error:nil];
    });
    return percentNumberRegex;
}

+ (NSRegularExpression *)iOSTokenRegex {
    static dispatch_once_t onceToken;
    static NSRegularExpression *iOSTokenRegex;
    dispatch_once(&onceToken, ^{
        iOSTokenRegex = [NSRegularExpression regularExpressionWithPattern:@"%([0-9]*)\\$?([@dDuUxXoOfeEgGcCsSpaAF])" options:0 error:nil];
    });
    return iOSTokenRegex;
}

- (void)assertLprojFiles:(NSArray *)lprojFiles withTranslationStringsInDirectory:(NSString *)directory haveNoMatchesWithRegex:(NSRegularExpression *)regex {
    XCTAssertNotNil(regex);
    for (NSString *lprojFileName in lprojFiles) {
        if (![TWNStringsTests localeForLprojFilenameIsAvailableOniOS:lprojFileName]) {
            continue;
        }
        NSDictionary *stringsDict = [self getTranslationStringsDictFromLprogAtPath:[directory stringByAppendingPathComponent:lprojFileName]];
        for (NSString *key in stringsDict) {
            NSString *localizedString = stringsDict[key];
            NSTextCheckingResult *result = [regex firstMatchInString:localizedString options:0 range:NSMakeRange(0, localizedString.length)];
            XCTAssertNil(result, @"Invalid character in string: %@ for key: %@ in locale: %@", localizedString, key, lprojFileName);
        }
    }
}

- (void)assertLprojFiles:(NSArray *)lprojFiles withTranslationStringsInDirectory:(NSString *)directory doesNotContain:(NSString *)banned {
    XCTAssertNotNil(banned);
    NSString * bannedUpper = [banned uppercaseString];
    for (NSString *lprojFileName in lprojFiles) {
        if (![TWNStringsTests localeForLprojFilenameIsAvailableOniOS:lprojFileName]) {
            continue;
        }
        NSDictionary *stringsDict = [self getTranslationStringsDictFromLprogAtPath:[directory stringByAppendingPathComponent:lprojFileName]];
        for (NSString *key in stringsDict) {
            NSString *localizedString = stringsDict[key];
            BOOL doesContainBannedString = [[localizedString uppercaseString] containsString:bannedUpper];
            XCTAssertFalse(doesContainBannedString, @"Invalid substring %@ found in: %@ for key: %@ in locale: %@", banned, localizedString, key, lprojFileName);
        }
    }
}

- (void)testiOSTranslationStringForTWNSubstitutionShortcuts {
    [self assertLprojFiles:TWNStringsTests.iOSLprojFiles withTranslationStringsInDirectory:TWNStringsTests.bundleRoot haveNoMatchesWithRegex:TWNStringsTests.twnTokenRegex];
}

- (void)testIncomingTranslationStringForReversedSubstitutionShortcuts {
    [self assertLprojFiles:TWNStringsTests.twnLprojFiles withTranslationStringsInDirectory:TWNStringsTests.twnLocalizationsDirectory haveNoMatchesWithRegex:TWNStringsTests.reverseTWNTokenRegex];
}

- (void)testiOSTranslationStringForReversedSubstitutionShortcuts {
    [self assertLprojFiles:TWNStringsTests.iOSLprojFiles withTranslationStringsInDirectory:TWNStringsTests.bundleRoot haveNoMatchesWithRegex:TWNStringsTests.reverseiOSTokenRegex];
}

- (void)testIncomingTranslationStringForPercentTokens {
    [self assertLprojFiles:TWNStringsTests.twnLprojFiles withTranslationStringsInDirectory:TWNStringsTests.twnLocalizationsDirectory haveNoMatchesWithRegex:TWNStringsTests.percentNumberRegex];
}

+ (NSRegularExpression *)htmlTagRegex {
    static NSRegularExpression *htmlTagRegex;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        htmlTagRegex = [NSRegularExpression regularExpressionWithPattern:@"(<[^>]*>)([^<]*)" options:NSRegularExpressionCaseInsensitive error:nil];
    });
    return htmlTagRegex;
}

- (void)testIncomingTranslationStringForHTML {
    [self assertLprojFiles:TWNStringsTests.twnLprojFiles withTranslationStringsInDirectory:TWNStringsTests.bundleRoot haveNoMatchesWithRegex:TWNStringsTests.htmlTagRegex];
}

- (void)testIncomingTranslationStringForNBSP {
    [self assertLprojFiles:TWNStringsTests.twnLprojFiles withTranslationStringsInDirectory:TWNStringsTests.bundleRoot doesNotContain:@"&nbsp;"];
}

- (void)testIncomingTranslationStringForBracketSubstitutions {
    for (NSString *lprojFileName in TWNStringsTests.twnLprojFiles) {
        if (![lprojFileName isEqualToString:@"qqq.lproj"]) {
            NSDictionary *stringsDict = [self getTranslationStringsDictFromLprogAtPath:[TWNStringsTests.bundleRoot stringByAppendingPathComponent:lprojFileName]];
            NSDictionary *pluralizableStringsDict = [self getPluralizableStringsDictFromLprogAtPath:[TWNStringsTests.bundleRoot stringByAppendingPathComponent:lprojFileName]];
            for (NSString *key in stringsDict) {
                NSString *localizedString = stringsDict[key];
                if ([localizedString containsString:@"{{"]) {
                    NSString *lowercaseString = localizedString.lowercaseString;
                    if ([lowercaseString containsString:@"{{plural:"]) {
                        XCTAssertNotNil([pluralizableStringsDict objectForKey:key], @"Localizable string %@ in %@ with PLURAL: needs an entry in the corresponding stringsdict file. This likely means that this language's Localizable.stringsdict hasn't been added to the project yet.", key, lprojFileName);
                    } else if (![lowercaseString containsString:@"{{formatnum:$"]) {
                        XCTAssertTrue(false, @"%@ in %@ has unsupported {{ }} in localization.", key, lprojFileName);
                    }
                }
            }
        }
    }
}

- (void)testiOSTranslationStringForBracketSubstitutionsAndMismatchedTokens {
    NSDictionary *enStrings = [self getTranslationStringsDictFromLprogAtPath:[TWNStringsTests.bundleRoot stringByAppendingPathComponent:@"en.lproj"]];
    NSMutableDictionary *enTokensByKey = [NSMutableDictionary dictionaryWithCapacity:enStrings.count];
    for (NSString *lprojFileName in TWNStringsTests.iOSLprojFiles) {
        if (![lprojFileName isEqualToString:@"qqq.lproj"]) {
            NSDictionary *stringsDict = [self getTranslationStringsDictFromLprogAtPath:[TWNStringsTests.bundleRoot stringByAppendingPathComponent:lprojFileName]];
            NSDictionary *pluralizableStringsDict = [self getPluralizableStringsDictFromLprogAtPath:[TWNStringsTests.bundleRoot stringByAppendingPathComponent:lprojFileName]];
            for (NSString *key in stringsDict) {
                NSString *localizedString = stringsDict[key];
                if ([localizedString containsString:@"{{"]) {
                    NSString *lowercaseString = localizedString.lowercaseString;
                    if ([lowercaseString containsString:@"{{plural:%"]) {
                        XCTAssertNotNil([pluralizableStringsDict objectForKey:key], @"Localizable string %@ in %@ with PLURAL: needs an entry in the corresponding stringsdict file. This likely means that this language's Localizable.stringsdict hasn't been added to the project yet.", key, lprojFileName);

                    } else {
                        XCTAssertTrue(false, @"Unsupported {{ }} in localization");
                    }
                }

                NSMutableDictionary *localizedTokens = [NSMutableDictionary new];
                NSRegularExpression *tokenRegex = [TWNStringsTests iOSTokenRegex];
                [tokenRegex enumerateMatchesInString:localizedString
                                             options:0
                                               range:NSMakeRange(0, localizedString.length)
                                          usingBlock:^(NSTextCheckingResult *_Nullable result, NSMatchingFlags flags, BOOL *_Nonnull stop) {
                                              NSString *tokenKey = [tokenRegex replacementStringForResult:result inString:localizedString offset:0 template:@"$1"];
                                              if ([tokenKey isEqualToString:@""]) {
                                                  tokenKey = @"1";
                                                  XCTAssertNil(localizedTokens[tokenKey], @"There can only be one unordered token in a localization string. Switch to ordered tokens:\n%@\n%@", key, localizedString);
                                              }
                                              NSString *value = [tokenRegex replacementStringForResult:result inString:localizedString offset:0 template:@"$2"];
                                              localizedTokens[tokenKey] = value;
                                          }];

                NSString *enString = enStrings[key];
                NSMutableDictionary *enTokens = enTokensByKey[key];
                if (enString) {
                    if (!enTokens) {
                        enTokens = [NSMutableDictionary new];
                        [tokenRegex enumerateMatchesInString:enString
                                                     options:0
                                                       range:NSMakeRange(0, enString.length)
                                                  usingBlock:^(NSTextCheckingResult *_Nullable result, NSMatchingFlags flags, BOOL *_Nonnull stop) {
                                                      NSString *tokenKey = [tokenRegex replacementStringForResult:result inString:enString offset:0 template:@"$1"];
                                                      if ([tokenKey isEqualToString:@""]) {
                                                          tokenKey = @"1";
                                                          XCTAssertNil(enTokens[tokenKey], @"There can only be one unordered token in a localization string. Switch to ordered tokens:\n%@\n%@", key, enString);
                                                      }
                                                      NSString *value = [tokenRegex replacementStringForResult:result inString:enString offset:0 template:@"$2"];
                                                      enTokens[tokenKey] = value;
                                                  }];
                        enTokensByKey[key] = enTokens;
                    }

                    XCTAssertEqualObjects(localizedTokens, enTokens, @"%@ translation for %@ has incorrect tokens:\n%@\n%@", lprojFileName, key, enString, localizedString);
                }
            }
        }
    }
}

- (NSArray *)unbundledLprojFiles {
    NSMutableArray *files = [TWNStringsTests.twnLprojFiles mutableCopy];
    [files removeObjectsInArray:TWNStringsTests.bundledLprojFiles];
    return files;
}

- (NSArray *)unbundledLprojFilesWithTranslations {
    // unbundled lProj's containing "Localizable.strings"
    return
        [self.unbundledLprojFiles wmf_select:^BOOL(NSString *lprojFileName) {
            BOOL isDirectory = NO;
            NSString *localizableStringsFilePath =
                [[TWNStringsTests.twnLocalizationsDirectory stringByAppendingPathComponent:lprojFileName] stringByAppendingPathComponent:@"Localizable.strings"];
            return [[NSFileManager defaultManager] fileExistsAtPath:localizableStringsFilePath isDirectory:&isDirectory];
        }];
}

+ (NSSet<NSString *> *)supportedLocales {
    static dispatch_once_t onceToken;
    static NSSet<NSString *> *supportedLocales;
    dispatch_once(&onceToken, ^{
        NSArray *lowercaseAvailableLocales = [[NSLocale availableLocaleIdentifiers] wmf_map:^id(NSString *locale) {
            return [locale lowercaseString];
        }];
        supportedLocales = [NSSet setWithArray:lowercaseAvailableLocales];
    });
    return supportedLocales;
}

+ (BOOL)localeForLprojFilenameIsAvailableOniOS:(NSString *)lprojFileName {
    NSString *localeIdentifier = [[lprojFileName substringToIndex:lprojFileName.length - 6] lowercaseString]; //remove .lproj suffix
    return [[TWNStringsTests supportedLocales] containsObject:localeIdentifier];
}

- (void)testAllSupportedTranslatedLanguagesWereAddedToProjectLocalizations {
    // Fails if any supported languages have translations (in "Localizable.strings") but are
    // not yet bundled in the project.
    // So, if this test fails, the languages listed will need to be added these to the project's localizations.
    NSArray *files = [self.unbundledLprojFilesWithTranslations mutableCopy];
    for (NSString *file in files) {
        XCTAssert(![TWNStringsTests localeForLprojFilenameIsAvailableOniOS:file], @"Missing supported translation for %@", file);
    }
}

- (void)testKeysForUnderscores {
    for (NSString *lprojFileName in TWNStringsTests.twnLprojFiles) {
        NSDictionary *stringsDict = [self getTranslationStringsDictFromLprogAtPath:[TWNStringsTests.bundleRoot stringByAppendingPathComponent:lprojFileName]];
        for (NSString *key in stringsDict) {
            // Keys use dash "-" separators.
            XCTAssertFalse([key containsString:@"_"]);
        }
    }
}

// Translators need context for all substitutions. If a string has any substitutions, such as "$1" or "$2" etc, the string's comment needs to explain what will be substituted in place of "$1", "$2" etc.
- (void)testiOSTranslationCommentsForMentionOfEachSubstitution {
    NSDictionary *enStrings = [self getDictFromPListAtPath:[[TWNStringsTests.twnLocalizationsDirectory stringByAppendingPathComponent:@"en.lproj"] stringByAppendingPathComponent:@"Localizable.strings"]];
    NSDictionary *qqqStrings = [self getDictFromPListAtPath:[[TWNStringsTests.twnLocalizationsDirectory stringByAppendingPathComponent:@"qqq.lproj"] stringByAppendingPathComponent:@"Localizable.strings"]];
    for (NSString *enKey in enStrings) {
        // This test assumes each EN key is also present in QQQ.
        XCTAssertTrue([qqqStrings valueForKey:enKey], @"Expected en key in qqq");

        NSString *enString = enStrings[enKey];
        NSString *qqqString = qqqStrings[enKey];
        NSArray<NSTextCheckingResult *> *enSubstitutionMatches = [TWNStringsTests.twnTokenRegex matchesInString:enString options:0 range:NSMakeRange(0, enString.length)];
        NSArray<NSTextCheckingResult *> *qqqSubstitutionMatches = [TWNStringsTests.twnTokenRegex matchesInString:qqqString options:0 range:NSMakeRange(0, qqqString.length)];

        for (NSTextCheckingResult *enMatch in enSubstitutionMatches) {
            NSString *enMatchString = [enString substringWithRange:enMatch.range];
            BOOL didFindEnMatchStringAtLeastOnceInQQQMatchString = NO;

            for (NSTextCheckingResult *qqqMatch in qqqSubstitutionMatches) {
                NSString *qqqMatchString = [qqqString substringWithRange:qqqMatch.range];
                if ([qqqMatchString isEqualToString:enMatchString]) {
                    didFindEnMatchStringAtLeastOnceInQQQMatchString = YES;
                    break;
                }
            }

            XCTAssertTrue(didFindEnMatchStringAtLeastOnceInQQQMatchString, @"\n\tExpected each substitution (i.e. \"$1\") in string is mentioned at least once in its comment.\n\t\tString: \"%@\"\n\t\tComment: \"%@\"\n\t\tKey: \"%@\"\n\n", [enString stringByReplacingOccurrencesOfString:@"\n" withString:@"\\n"], [qqqString stringByReplacingOccurrencesOfString:@"\n" withString:@"\\n"], enKey);

            if (!didFindEnMatchStringAtLeastOnceInQQQMatchString) {
                // No need keep testing if a string already failed our assertion once.
                break;
            }
        }
    }
}

// Translators have been know to add "{{plural..." syntax to strings which don't yet have "{{plural..." in EN, which means the string won't be correctly resolved.
- (void)testIncomingTranslationStringForBracketSubstitutionsNotPresentInEN {
    NSDictionary *enPluralizableStringsDict = [self getPluralizableStringsDictFromLprogAtPath:[TWNStringsTests.bundleRoot stringByAppendingPathComponent:@"en.lproj"]];
    for (NSString *lprojFileName in TWNStringsTests.twnLprojFiles) {
        if (![lprojFileName isEqualToString:@"qqq.lproj"] && ![lprojFileName isEqualToString:@"en.lproj"]) {
            NSDictionary *translationPluralizableStringsDict = [self getPluralizableStringsDictFromLprogAtPath:[TWNStringsTests.bundleRoot stringByAppendingPathComponent:lprojFileName]];
            for (NSString *key in translationPluralizableStringsDict) {
                XCTAssertNotNil([enPluralizableStringsDict objectForKey:key], @"\n\n\"%@\" translation containing plurals syntax received for \"%@\" string. The original EN string...\n\thttps://translatewiki.net/w/i.php?title=Wikimedia:Wikipedia-ios-%@/en&action=edit\n...doesn't have (or possibly need) plural syntax - either plural syntax will need to be added to the EN string or the translation...\n\thttps://translatewiki.net/w/i.php?title=Wikimedia:Wikipedia-ios-%@/%@&action=edit\n...will need to be updated to remove plural syntax.\n(Note: after loading the link above you can tap the \"Ask question\" button to pre-fill a Phabricator ticket for asking `i18n` folks for assistance for this string)\n\n", lprojFileName, key, key, key, [lprojFileName stringByReplacingOccurrencesOfString:@".lproj" withString:@""]);
            }
        }
    }
}

- (void)tearDown {
    [super tearDown];
}

@end