#import <AppKit/AppKit.h>
#import <WebKit/WebKit.h>
#import "../src-tauri/src/navigation.m"

static void check(BOOL condition, NSString *message) {
    if (!condition) {
        fprintf(stderr, "FAIL: %s\n", message.UTF8String);
        exit(1);
    }
}

static void waitUntil(BOOL (^condition)(void), NSString *message) {
    NSDate *deadline = [NSDate dateWithTimeIntervalSinceNow:10];
    while (!condition() && deadline.timeIntervalSinceNow > 0) {
        [NSRunLoop.currentRunLoop runUntilDate:[NSDate dateWithTimeIntervalSinceNow:0.01]];
    }
    check(condition(), message);
}

static id evaluate(WKWebView *webview, NSString *script) {
    __block BOOL finished = NO;
    __block id result;
    [webview evaluateJavaScript:script completionHandler:^(id value, NSError *error) {
        check(error == nil, error.localizedDescription);
        result = value;
        finished = YES;
    }];
    waitUntil(^BOOL { return finished; }, @"JavaScript must finish after the confirmation is dismissed");
    return result;
}

static NSButton *findButton(NSView *view, NSString *title) {
    if ([view isKindOfClass:NSButton.class] && [((NSButton *)view).title isEqualToString:title]) {
        return (NSButton *)view;
    }
    for (NSView *child in view.subviews) {
        NSButton *button = findButton(child, title);
        if (button) { return button; }
    }
    return nil;
}

static BOOL containsText(NSView *view, NSString *text) {
    if ([view isKindOfClass:NSTextField.class] && [((NSTextField *)view).stringValue isEqualToString:text]) {
        return YES;
    }
    for (NSView *child in view.subviews) {
        if (containsText(child, text)) { return YES; }
    }
    return NO;
}

@interface WorkspaceUI : NSObject <WKUIDelegate>
@property(nonatomic) BOOL closed;
@property(nonatomic) BOOL uploaded;
@end

@implementation WorkspaceUI
- (void)webViewDidClose:(WKWebView *)webView { self.closed = YES; }
- (void)webView:(WKWebView *)webView runOpenPanelWithParameters:(WKOpenPanelParameters *)parameters
        initiatedByFrame:(WKFrameInfo *)frame completionHandler:(void (^)(NSArray<NSURL *> *))completionHandler {
    self.uploaded = YES;
    completionHandler(nil);
}
@end

@interface WorkspacePages : NSObject <WKURLSchemeHandler, WKNavigationDelegate>
@property(nonatomic) NSUInteger finished;
@end

@implementation WorkspacePages
- (void)webView:(WKWebView *)webView startURLSchemeTask:(id<WKURLSchemeTask>)task {
    NSData *body = [[NSString stringWithFormat:@"<html><body>%@<input value='draft'></body></html>", task.request.URL.path]
        dataUsingEncoding:NSUTF8StringEncoding];
    NSURLResponse *response = [[NSURLResponse alloc] initWithURL:task.request.URL MIMEType:@"text/html"
                                         expectedContentLength:body.length textEncodingName:@"utf-8"];
    [task didReceiveResponse:response];
    [task didReceiveData:body];
    [task didFinish];
}
- (void)webView:(WKWebView *)webView stopURLSchemeTask:(id<WKURLSchemeTask>)task {}
- (void)webView:(WKWebView *)webView didFinishNavigation:(WKNavigation *)navigation {
    self.finished++;
}
@end

int main(void) {
    @autoreleasepool {
        [NSApplication sharedApplication];
        WorkspacePages *pages = [WorkspacePages new];
        WKWebViewConfiguration *configuration = [WKWebViewConfiguration new];
        configuration.websiteDataStore = WKWebsiteDataStore.nonPersistentDataStore;
        [configuration setURLSchemeHandler:pages forURLScheme:@"kanban-test"];
        WKWebView *webview = [[WKWebView alloc] initWithFrame:NSMakeRect(0, 0, 800, 600) configuration:configuration];
        webview.navigationDelegate = pages;
        WorkspaceUI *originalUI = [WorkspaceUI new];
        webview.UIDelegate = originalUI;
        check(!webview.allowsBackForwardNavigationGestures, @"WebKit defaults to disabled gestures");
        install_workspace_navigation((__bridge void *)webview);
        id<WKUIDelegate> installedUI = webview.UIDelegate;
        install_workspace_navigation((__bridge void *)webview);
        check(webview.UIDelegate == installedUI, @"Installing workspace behavior twice must retain the same delegate");
        check([installedUI respondsToSelector:@selector(webViewDidClose:)], @"Existing popup callbacks must remain available");
        [installedUI webViewDidClose:webview];
        check(originalUI.closed, @"Existing popup callbacks must reach the original delegate");
        check([installedUI respondsToSelector:@selector(webView:runOpenPanelWithParameters:initiatedByFrame:completionHandler:)],
            @"Existing file upload callbacks must remain available");
        check(webview.allowsBackForwardNavigationGestures, @"The workspace must enable WebKit's interactive gestures");
        check(webview.configuration.userContentController.userScripts.count == 0, @"Enabling gestures must not inject a history adapter");
        check([webview goBack] == nil && [webview goForward] == nil, @"Empty history must not navigate");

        [webview loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"kanban-test://workspace/first"]]];
        waitUntil(^BOOL { return pages.finished == 1; }, @"First page must load");
        check(!webview.canGoBack && !webview.canGoForward, @"The first page must have no navigation target");
        [webview loadRequest:[NSURLRequest requestWithURL:[NSURL URLWithString:@"kanban-test://workspace/second"]]];
        waitUntil(^BOOL { return pages.finished == 2; }, @"Second page must load");
        check(webview.canGoBack && !webview.canGoForward, @"Native history must retain the first page");
        check([webview goBack] != nil, @"Native back navigation must start");
        waitUntil(^BOOL { return pages.finished == 3; }, @"Native back navigation must complete");
        check([webview.URL.path isEqualToString:@"/first"] && !webview.canGoBack && webview.canGoForward,
              @"Back must restore the first page and retain forward history");
        check([webview goBack] == nil, @"Back at the first page must leave it in place");
        check([webview goForward] != nil, @"Native forward navigation must start");
        waitUntil(^BOOL { return pages.finished == 4; }, @"Native forward navigation must complete");
        check([webview.URL.path isEqualToString:@"/second"] && webview.canGoBack && !webview.canGoForward,
              @"Forward must restore the second page");
        check(webview.allowsBackForwardNavigationGestures, @"Native gestures must remain enabled across page navigation");

        NSWindow *window = [[NSWindow alloc] initWithContentRect:NSMakeRect(0, 0, 800, 600)
            styleMask:NSWindowStyleMaskTitled backing:NSBackingStoreBuffered defer:NO];
        window.releasedWhenClosed = NO;
        window.title = @"KanbanGit navigation test";
        window.contentView = webview;
        [window orderFront:nil];
        evaluate(webview, @"document.body.innerHTML = `<input id='duplicate' type='radio'><input id='draft' value='Unsaved project'><input id='upload' type='file'><a id='back' href='#back'>Back</a>`; window.visits = 0; document.querySelector('#back').onclick = event => { event.preventDefault(); if (!document.querySelector('#duplicate').checked || confirm('Discard unsaved changes?')) window.visits++; }; true;");
        evaluate(webview, @"document.querySelector('#upload').click()");
        waitUntil(^BOOL { return originalUI.uploaded; }, @"File selection must still reach the original UI delegate");
        evaluate(webview, @"document.querySelector('#back').click()");
        check([evaluate(webview, @"window.visits") intValue] == 1, @"Pristine forms must navigate without a confirmation");
        evaluate(webview, @"document.querySelector('#duplicate').click()");
        for (NSString *choice in @[@"Cancel", @"OK", @"Cancel", @"OK"]) {
            __block BOOL finished = NO;
            [webview evaluateJavaScript:@"document.querySelector('#back').click()" completionHandler:^(id result, NSError *error) {
                check(error == nil, error.localizedDescription);
                finished = YES;
            }];
            waitUntil(^BOOL { return window.attachedSheet != nil; }, @"Dirty form navigation must show a native confirmation");
            check(!finished, @"The original click must wait for the user's decision");
            check(containsText(window.attachedSheet.contentView, @"workspace"), @"The confirmation must identify the requesting website");
            check(containsText(window.attachedSheet.contentView, @"Discard unsaved changes?"), @"The confirmation must show the application's message");
            NSButton *button = findButton(window.attachedSheet.contentView, choice);
            check(button != nil, @"The native confirmation must offer OK and Cancel");
            [button performClick:nil];
            waitUntil(^BOOL { return finished && window.attachedSheet == nil; }, @"Dismissal must release the original navigation");
            check([evaluate(webview, @"document.querySelector('#draft').value") isEqualToString:@"Unsaved project"],
                @"Cancelling a confirmation must preserve the draft");
        }
        check([evaluate(webview, @"window.visits") intValue] == 3, @"Only accepted visits must run, exactly once each");
        window.contentView = nil;
        check(![evaluate(webview, @"confirm('Detached view')") boolValue], @"A detached view must cancel and release JavaScript immediately");
        [window orderOut:nil];
        [window close];
        puts("PASS: WebKit interactive gesture configuration, full-page back/forward, native confirmations and delegate forwarding");
    }
}