Tweak.m

#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
#import <objc/runtime.h>

static NSString * const kTargetBundleID = @"com.mfcloudcalculate.123networkdisk";

static BOOL (*orig_NSURL_startAccessing)(id self, SEL _cmd) = NULL;
static void (*orig_NSURL_stopAccessing)(id self, SEL _cmd) = NULL;

static void (*orig_documentPicker_didPickDocumentAtURL)(id self, SEL _cmd, UIDocumentPickerViewController *controller, NSURL *url) = NULL;
static BOOL (*orig_application_openURL_options)(id self, SEL _cmd, UIApplication *application, NSURL *url, NSDictionary *options) = NULL;
static BOOL (*orig_application_openURL_source_annotation)(id self, SEL _cmd, UIApplication *application, NSURL *url, NSString *sourceApplication, id annotation) = NULL;
static BOOL (*orig_application_handleOpenURL)(id self, SEL _cmd, UIApplication *application, NSURL *url) = NULL;
static BOOL (*orig_application_didFinishLaunching)(id self, SEL _cmd, UIApplication *application, NSDictionary *launchOptions) = NULL;
static BOOL (*orig_application_willFinishLaunching)(id self, SEL _cmd, UIApplication *application, NSDictionary *launchOptions) = NULL;

static id (*orig_picker_initWithDocumentTypes_inMode)(id self, SEL _cmd, id documentTypes, NSInteger mode) = NULL;
static id (*orig_picker_initForOpeningContentTypes_asCopy)(id self, SEL _cmd, id contentTypes, BOOL asCopy) = NULL;

#pragma mark - Helpers

static BOOL FPCFIsTargetApp(void) {
    return [[[NSBundle mainBundle] bundleIdentifier] isEqualToString:kTargetBundleID];
}

static NSURL *FPCFDocumentsURL(void) {
    NSURL *url = [[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] firstObject];
    if (!url) {
        url = [NSURL fileURLWithPath:[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"] isDirectory:YES];
    }
    [[NSFileManager defaultManager] createDirectoryAtURL:url withIntermediateDirectories:YES attributes:nil error:nil];
    return url;
}

static void FPCFWriteStatus(NSString *line) {
    @try {
        NSURL *url = [FPCFDocumentsURL() URLByAppendingPathComponent:@"FilePickerCopyFixStatus.txt" isDirectory:NO];

        NSString *old = [NSString stringWithContentsOfURL:url encoding:NSUTF8StringEncoding error:nil];
        if (!old) old = @"";

        NSDateFormatter *formatter = [NSDateFormatter new];
        formatter.dateFormat = @"yyyy-MM-dd HH:mm:ss";

        NSString *newLine = [NSString stringWithFormat:@"%@ %@\n", [formatter stringFromDate:[NSDate date]], line ?: @""];
        NSString *content = [old stringByAppendingString:newLine];

        if (content.length > 30000) {
            content = [content substringFromIndex:content.length - 22000];
        }

        [content writeToURL:url atomically:YES encoding:NSUTF8StringEncoding error:nil];
    } @catch (__unused NSException *exception) {
    }
}

static NSString *FPCFURLInfo(NSURL *url) {
    if (![url isKindOfClass:[NSURL class]]) return @"<not NSURL>";
    return url.isFileURL ? (url.path ?: @"<nil path>") : (url.absoluteString ?: @"<nil url>");
}

static void FPCFCleanOldCopies(void) {
    @try {
        NSURL *oldInbox = [FPCFDocumentsURL() URLByAppendingPathComponent:@"FilePickerCopyFixInbox" isDirectory:YES];
        if ([[NSFileManager defaultManager] fileExistsAtPath:oldInbox.path]) {
            NSError *error = nil;
            [[NSFileManager defaultManager] removeItemAtURL:oldInbox error:&error];
            FPCFWriteStatus([NSString stringWithFormat:@"cleanup old FilePickerCopyFixInbox: %@", error ?: @"OK"]);
        }
    } @catch (NSException *exception) {
        FPCFWriteStatus([NSString stringWithFormat:@"cleanup exception: %@", exception]);
    }
}

#pragma mark - NSURL security scope fix

static BOOL fixed_NSURL_startAccessing(id self, SEL _cmd) {
    BOOL result = NO;

    if (orig_NSURL_startAccessing) {
        result = orig_NSURL_startAccessing(self, _cmd);
    }

    if (FPCFIsTargetApp() && [self isKindOfClass:[NSURL class]]) {
        NSURL *url = (NSURL *)self;
        if (url.isFileURL) {
            /*
             123云盘原 Swift 逻辑会在 startAccessingSecurityScopedResource 返回 false 时直接 return。
             侧载/重签后，本地 tmp Inbox 文件经常返回 false。
             这里强制返回 YES，但不复制文件，避免占用 Documents 存储。
            */
            FPCFWriteStatus([NSString stringWithFormat:@"startAccess original=%d forced=1 path=%@", result ? 1 : 0, url.path]);
            return YES;
        }
    }

    return result;
}

static void fixed_NSURL_stopAccessing(id self, SEL _cmd) {
    if (orig_NSURL_stopAccessing) {
        orig_NSURL_stopAccessing(self, _cmd);
    }
}

#pragma mark - AppDelegate exact hooks, no-copy

static void fixed_documentPicker_didPickDocumentAtURL(id self, SEL _cmd, UIDocumentPickerViewController *controller, NSURL *url) {
    FPCFWriteStatus([NSString stringWithFormat:@"documentPicker passthrough: %@", FPCFURLInfo(url)]);

    if (orig_documentPicker_didPickDocumentAtURL) {
        orig_documentPicker_didPickDocumentAtURL(self, _cmd, controller, url);
    }
}

static BOOL fixed_application_openURL_options(id self, SEL _cmd, UIApplication *application, NSURL *url, NSDictionary *options) {
    FPCFWriteStatus([NSString stringWithFormat:@"openURL options passthrough: %@", FPCFURLInfo(url)]);

    if (orig_application_openURL_options) {
        return orig_application_openURL_options(self, _cmd, application, url, options);
    }

    return NO;
}

static BOOL fixed_application_openURL_source_annotation(id self, SEL _cmd, UIApplication *application, NSURL *url, NSString *sourceApplication, id annotation) {
    FPCFWriteStatus([NSString stringWithFormat:@"openURL source passthrough: %@ source=%@", FPCFURLInfo(url), sourceApplication ?: @"<nil>"]);

    if (orig_application_openURL_source_annotation) {
        return orig_application_openURL_source_annotation(self, _cmd, application, url, sourceApplication, annotation);
    }

    return NO;
}

static BOOL fixed_application_handleOpenURL(id self, SEL _cmd, UIApplication *application, NSURL *url) {
    FPCFWriteStatus([NSString stringWithFormat:@"handleOpenURL passthrough: %@", FPCFURLInfo(url)]);

    if (orig_application_handleOpenURL) {
        return orig_application_handleOpenURL(self, _cmd, application, url);
    }

    return NO;
}

static BOOL fixed_application_didFinishLaunching(id self, SEL _cmd, UIApplication *application, NSDictionary *launchOptions) {
    NSURL *url = [launchOptions isKindOfClass:[NSDictionary class]] ? launchOptions[UIApplicationLaunchOptionsURLKey] : nil;
    if (url) {
        FPCFWriteStatus([NSString stringWithFormat:@"didFinish launch URL passthrough: %@", FPCFURLInfo(url)]);
    } else {
        FPCFWriteStatus(@"didFinish no launch URL");
    }

    if (orig_application_didFinishLaunching) {
        return orig_application_didFinishLaunching(self, _cmd, application, launchOptions);
    }

    return YES;
}

static BOOL fixed_application_willFinishLaunching(id self, SEL _cmd, UIApplication *application, NSDictionary *launchOptions) {
    NSURL *url = [launchOptions isKindOfClass:[NSDictionary class]] ? launchOptions[UIApplicationLaunchOptionsURLKey] : nil;
    if (url) {
        FPCFWriteStatus([NSString stringWithFormat:@"willFinish launch URL passthrough: %@", FPCFURLInfo(url)]);
    }

    if (orig_application_willFinishLaunching) {
        return orig_application_willFinishLaunching(self, _cmd, application, launchOptions);
    }

    return YES;
}

#pragma mark - Keep document picker import/copy mode

static id fixed_picker_initWithDocumentTypes_inMode(id self, SEL _cmd, id documentTypes, NSInteger mode) {
    if (orig_picker_initWithDocumentTypes_inMode) {
        return orig_picker_initWithDocumentTypes_inMode(self, _cmd, documentTypes, 0); // UIDocumentPickerModeImport
    }
    return self;
}

static id fixed_picker_initForOpeningContentTypes_asCopy(id self, SEL _cmd, id contentTypes, BOOL asCopy) {
    if (orig_picker_initForOpeningContentTypes_asCopy) {
        return orig_picker_initForOpeningContentTypes_asCopy(self, _cmd, contentTypes, YES);
    }
    return self;
}

#pragma mark - Swizzle helpers

static Class FPCFAppDelegateClass(void) {
    Class cls = objc_getClass("_TtC6Runner11AppDelegate");
    if (!cls) cls = NSClassFromString(@"Runner.AppDelegate");
    return cls;
}

static void replaceInstanceMethod(Class cls, SEL sel, IMP newImp, IMP *oldImp) {
    if (!cls || !sel || !newImp || !oldImp) {
        FPCFWriteStatus([NSString stringWithFormat:@"hook skipped: %@", NSStringFromSelector(sel)]);
        return;
    }

    Method method = class_getInstanceMethod(cls, sel);
    if (!method) {
        FPCFWriteStatus([NSString stringWithFormat:@"method not found: %@ on %@", NSStringFromSelector(sel), cls]);
        return;
    }

    IMP current = method_getImplementation(method);
    if (current == newImp) return;

    *oldImp = method_setImplementation(method, newImp);
    FPCFWriteStatus([NSString stringWithFormat:@"hooked: %@ on %@", NSStringFromSelector(sel), cls]);
}

__attribute__((constructor))
static void FilePickerCopyFixInit(void) {
    @autoreleasepool {
        if (!FPCFIsTargetApp()) return;

        FPCFWriteStatus(@"AccessNoCopy loaded");
        FPCFCleanOldCopies();

        replaceInstanceMethod([NSURL class],
                              @selector(startAccessingSecurityScopedResource),
                              (IMP)fixed_NSURL_startAccessing,
                              (IMP *)&orig_NSURL_startAccessing);

        replaceInstanceMethod([NSURL class],
                              @selector(stopAccessingSecurityScopedResource),
                              (IMP)fixed_NSURL_stopAccessing,
                              (IMP *)&orig_NSURL_stopAccessing);

        Class appDelegateClass = FPCFAppDelegateClass();

        replaceInstanceMethod(appDelegateClass,
                              @selector(documentPicker:didPickDocumentAtURL:),
                              (IMP)fixed_documentPicker_didPickDocumentAtURL,
                              (IMP *)&orig_documentPicker_didPickDocumentAtURL);

        replaceInstanceMethod(appDelegateClass,
                              @selector(application:openURL:options:),
                              (IMP)fixed_application_openURL_options,
                              (IMP *)&orig_application_openURL_options);

        replaceInstanceMethod(appDelegateClass,
                              @selector(application:openURL:sourceApplication:annotation:),
                              (IMP)fixed_application_openURL_source_annotation,
                              (IMP *)&orig_application_openURL_source_annotation);

        replaceInstanceMethod(appDelegateClass,
                              @selector(application:handleOpenURL:),
                              (IMP)fixed_application_handleOpenURL,
                              (IMP *)&orig_application_handleOpenURL);

        replaceInstanceMethod(appDelegateClass,
                              @selector(application:didFinishLaunchingWithOptions:),
                              (IMP)fixed_application_didFinishLaunching,
                              (IMP *)&orig_application_didFinishLaunching);

        replaceInstanceMethod(appDelegateClass,
                              @selector(application:willFinishLaunchingWithOptions:),
                              (IMP)fixed_application_willFinishLaunching,
                              (IMP *)&orig_application_willFinishLaunching);

        Class pickerClass = objc_getClass("UIDocumentPickerViewController");

        replaceInstanceMethod(pickerClass,
                              @selector(initWithDocumentTypes:inMode:),
                              (IMP)fixed_picker_initWithDocumentTypes_inMode,
                              (IMP *)&orig_picker_initWithDocumentTypes_inMode);

        replaceInstanceMethod(pickerClass,
                              @selector(initForOpeningContentTypes:asCopy:),
                              (IMP)fixed_picker_initForOpeningContentTypes_asCopy,
                              (IMP *)&orig_picker_initForOpeningContentTypes_asCopy);
    }
}