import { Component, inject, input, OnInit, output, signal } from '@angular/core';
import { MatPaginator, PageEvent } from '@angular/material/paginator';
import { ImageService } from '../../../services/ImageService';
import { Spinner } from '../../spinner/spinner';
import { ImageView } from '../../../models/ImageView.model';
import { MatCard, MatCardActions, MatCardContent, MatCardImage } from '@angular/material/card';
import { MatCheckbox } from '@angular/material/checkbox';
import { MatMenu, MatMenuItem, MatMenuTrigger } from '@angular/material/menu';
import { FaIconComponent } from '@fortawesome/angular-fontawesome';
import { faEllipsis } from '@fortawesome/free-solid-svg-icons';
import { MatButton } from '@angular/material/button';
import { MatDialog } from '@angular/material/dialog';
import { EditImageDialog } from './edit-image-dialog/edit-image-dialog';
import { SliceView } from '../../../models/SliceView.model';
import { ImageViewWithBlobUrl } from '../../../client-models/ImageViewWithBlobUrl';

@Component({
    selector: 'app-image-select',
    imports: [
        MatPaginator,
        Spinner,
        MatCard,
        MatCardImage,
        MatCardContent,
        MatCardActions,
        MatCheckbox,
        MatMenuTrigger,
        MatMenu,
        FaIconComponent,
        MatButton,
        MatMenuItem,
    ],
    templateUrl: './image-select.html',
    styleUrl: './image-select.css',
})
export class ImageSelect implements OnInit {
    public readonly select = output<ImageView | null>();
    public readonly selectedUsernameFilename = input<readonly [string, string] | null>(null);

    protected readonly currentPage = signal(0);
    protected readonly pageSize = signal(9);

    private readonly imageService = inject(ImageService);
    private readonly dialog = inject(MatDialog);

    protected readonly loadingImages = signal(false);
    protected readonly loadImagesError = signal<Error | null>(null);
    protected readonly imagesSlice = signal<SliceView<ImageViewWithBlobUrl> | null>(null);

    protected readonly imageCount = signal(0);

    protected readonly deleting = signal(false);
    protected readonly deleteError = signal<Error | null>(null);

    public ngOnInit(): void {
        this.loadImages();
    }

    private loadImages(): void {
        this.loadingImages.set(true);
        this.imageService
            .getOwnedImageViewsWithBlobUrls({
                page: this.currentPage(),
                size: this.pageSize(),
                sort: [
                    {
                        property: 'created',
                        order: 'DESC',
                    },
                ],
            })
            .subscribe({
                next: (sliceView) => {
                    sliceView.content.sort((a, b) => b.created.valueOf() - a.created.valueOf());
                    this.loadingImages.set(false);
                    this.imagesSlice.set(sliceView);
                },
                error: (e) => {
                    this.loadingImages.set(false);
                    this.loadImagesError.set(e);
                },
            });
        this.imageService.getOwnedImagesCount().subscribe({
            next: (count) => {
                this.imageCount.set(count);
            },
        });
    }

    protected onPage(pageEvent: PageEvent): void {
        if (pageEvent.pageIndex < this.currentPage()) {
            // backward
            this.currentPage.update((old) => Math.max(old - 1, 0));
        } else {
            // forward
            this.currentPage.update((old) => (this.imagesSlice()?.slice.hasNext ? old + 1 : old));
        }
        this.pageSize.set(pageEvent.pageSize);
        this.loadImages();
    }

    protected onImageClick(imageView: ImageView): void {
        if (this.isSelected(imageView)) {
            this.select.emit(null);
        } else {
            this.select.emit(imageView);
        }
    }

    protected isSelected(imageView: ImageView): boolean {
        const selectedUsernameFilename = this.selectedUsernameFilename();
        if (selectedUsernameFilename) {
            const [username, filename] = selectedUsernameFilename;
            return imageView.owner.username === username && imageView.filename === filename;
        }
        return false;
    }

    protected editImage(imageView: ImageView): void {
        this.dialog.open(EditImageDialog, {
            data: [imageView.owner.username, imageView.filename],
        });
    }

    protected deleteImage(imageView: ImageView): void {
        this.deleting.set(true);
        this.imageService.deleteImage(imageView.owner.username, imageView.filename).subscribe({
            next: () => {
                this.deleting.set(false);
                this.loadImages();
            },
            error: (e) => {
                this.deleting.set(false);
                this.deleteError.set(e);
            },
        });
    }

    protected readonly faEllipsis = faEllipsis;
}