//
//  HPShareExtensionHelper.m
//  HotPocket
//
//  Created by Tomek Wójcik on 27/09/2025.
//

#import <UniformTypeIdentifiers/UniformTypeIdentifiers.h>

#import "HPShareExtensionHelper.h"

#import "HPSharedItem.h"
#import "HPSharedItemsContainer.h"

@implementation HPShareExtensionHelper (HPShareExtensionHelperPrivate)

@end

@implementation HPShareExtensionHelper

-(instancetype)initWithContext:(NSExtensionContext *)context {
    if (self = [super init]) {
        self.context = context;
        self.items = [[HPSharedItemsContainer alloc] init];
    }
    
    return self;
}

-(void)processItems:(HPShareExtensionHelperHandleItemsCompletionHandler)completionHandler {
    // Depending on the app, the URL might be stored in `public.url` attachment or elsewhere.
    // For example, the YouTube app passes it in `public.plain-text`. Because of course it does.
    // Furthermore, for some bizarre reason the recommended way of extracting the URL when sharing from a browser
    // is to run a JS snippet and examine its output.
    // This method will iterate through all the shared items and their attachments and attempt to extract
    // the URL candidates.
    //
    // Also note that handler for `public.url` explicitly requests the payload to be corced to `NSURL *`. Leaving it
    // at `NSData *` would cause iOS to, wait for it!, fetch the URL and dump the response body in the payload :D.
    //
    // This is so _so_ *so* dumb. But hey, at least I learned how to to "chords" in CGD ¯\_(ツ)_/¯
    UTType *propertyListType = [UTType typeWithFilenameExtension:@"plist"];
    
    dispatch_group_t dispatchGroup = dispatch_group_create();
    dispatch_queue_t queue = dispatch_queue_create("HPShareExtensionHelper.processItems.queue", DISPATCH_QUEUE_SERIAL);
    
    for (NSExtensionItem *inputItem in self.context.inputItems) {
#ifdef DEBUG
        NSLog(@"-[HPShareExtensionHelper processItems:] inputItem.userInfo=`%@`", inputItem);
#endif
        [inputItem.attachments enumerateObjectsUsingBlock:^(NSItemProvider *attachment, NSUInteger index, BOOL *stop) {
            dispatch_group_enter(dispatchGroup);
            
            if ([attachment hasItemConformingToTypeIdentifier:propertyListType.identifier] == YES) {
                [attachment loadItemForTypeIdentifier:propertyListType.identifier
                                              options:nil
                                    completionHandler:^(NSDictionary *payload, NSError *error) {
                    dispatch_async(queue, ^{
                        self.items.primaryItem = [[HPSharedItem alloc] initWithPayload:payload
                                                                        typeIdentifier:propertyListType.identifier
                                                                                 error:error];
                        
                        dispatch_group_leave(dispatchGroup);
                    });
                }];
            } else if ([attachment hasItemConformingToTypeIdentifier:@"public.url"] == YES) {
                [attachment loadItemForTypeIdentifier:@"public.url"
                                              options:nil
                                    completionHandler:^(NSURL *payload, NSError *error) {
                    dispatch_async(queue, ^{
                        [self.items.candidateItems addObject:[[HPSharedItem alloc] initWithPayload:payload
                                                                                    typeIdentifier:@"public.url"
                                                                                             error:error]];
                        
                        dispatch_group_leave(dispatchGroup);
                    });
                }];
            } else if ([attachment hasItemConformingToTypeIdentifier:@"public.plain-text"] == YES) {
                [attachment loadItemForTypeIdentifier:@"public.plain-text"
                                              options:nil
                                    completionHandler:^(NSString *payload, NSError *error) {
                    dispatch_async(queue, ^{
                        [self.items.candidateItems addObject:[[HPSharedItem alloc] initWithPayload:payload
                                                                                    typeIdentifier:@"public.plain-text"
                                                                                             error:error]];
                        
                        dispatch_group_leave(dispatchGroup);
                    });
                }];
            } else {
                dispatch_group_leave(dispatchGroup);
            }
        }];
        
        dispatch_group_notify(dispatchGroup, dispatch_get_main_queue(), ^{
            NSURL *result = [self.items resolveURL];
            completionHandler(result);
        });
    }
}

@end