class EventFileList extends Shadow {
    constructor(existingAttachments, onDeleteExisting = null, onDeleteNew = null, onPreview = null) {
        super();
        this.existingAttachments = existingAttachments ?? [];
        this.newFiles = [];
        this.objectURLs = new Map();
        this.onDeleteExisting = onDeleteExisting;
        this.onDeleteNew = onDeleteNew;
        this.onPreview = onPreview;
    }

    update(files) {
        this.newFiles.push(...Array.from(files));
        this.rerender();
    }

    removeExisting(fileId) {
        this.existingAttachments = this.existingAttachments.filter(f => f.id !== fileId);
        this.rerender();
    }

    removeNew(index) {
        const file = this.newFiles[index];
        if (this.objectURLs.has(file)) {
            URL.revokeObjectURL(this.objectURLs.get(file));
            this.objectURLs.delete(file);
        }
        this.newFiles.splice(index, 1);
        this.rerender();
    }

    commitNew(insertedFiles) {
        this.newFiles.forEach(file => {
            if (this.objectURLs.has(file)) {
                URL.revokeObjectURL(this.objectURLs.get(file));
                this.objectURLs.delete(file);
            }
        });
        this.newFiles = [];
        this.existingAttachments = [...this.existingAttachments, ...insertedFiles];
        this.rerender();
    }

    getObjectURL(file) {
        if (!this.objectURLs.has(file)) {
            this.objectURLs.set(file, URL.createObjectURL(file));
        }
        return this.objectURLs.get(file);
    }

    render() {
        const hasFiles = this.existingAttachments.length > 0 || this.newFiles.length > 0;
        this.style.display = hasFiles ? "flex" : "none";
        this.style.padding = "1em";
        this.style.paddingTop = "0.5em";
        this.style.boxSizing = "border-box";

        VStack(() => {
            this.existingAttachments.forEach(file => {
                const isImage = file.type?.startsWith("image/");
                const url = `${config.SERVER}/db/images/events/${file.name}`
                const row = HStack(() => {
                    if (isImage) {
                        img(`${config.UI}/db/images/events/${file.name}`, "1.5em", "1.5em")
                            .objectFit("cover")
                            .borderRadius(3, px)
                            .flexShrink(0)
                    } else {
                        span("📎")
                    }
                    span(file.original_name ?? file.name)
                        .overflow("hidden")
                        .textOverflow("ellipsis")
                        .whiteSpace("nowrap")
                        .flex(1)

                    span(file.size_bytes != null ? `${(file.size_bytes / 1024).toFixed(1)} KB` : "")
                        .opacity(0.5)
                        .flexShrink(0)
                        .fontSize(0.85, rem)
                        .width("5em")

                    if (this.onDeleteExisting) {
                        span("×")
                            .color("var(--quillred)")
                            .opacity(0.7)
                            .fontSize(1.2, em)
                            .fontWeight("600")
                            .flexShrink(0)
                            .cursor("pointer")
                            .padding(0.5, em)
                            .margin(-0.5, em)
                            .onTap((e) => { e?.stopPropagation(); if (window.isMobile() === true) this.onDeleteExisting(file.id) })
                            .onClick((done, e) => { e?.stopPropagation(); if (done && window.isMobile() === false) this.onDeleteExisting(file.id) })
                    }
                })
                .alignItems("center")
                .gap(0.5, em)
                if (this.onPreview) {
                    row.cursor("pointer")
                        .onClick((done) => { if (done) this.onPreview(file, url) })
                }
            })

            this.newFiles.forEach((file, index) => {
                const isImage = file.type.startsWith("image/");
                const url = this.getObjectURL(file)
                const row = HStack(() => {
                    if (isImage) {
                        img(url, "1.5em", "1.5em")
                            .objectFit("cover")
                            .borderRadius(3, px)
                            .flexShrink(0)
                    } else {
                        span("📎")
                    }
                    span(file.name)
                        .overflow("hidden")
                        .textOverflow("ellipsis")
                        .whiteSpace("nowrap")
                        .flex(1)

                    span(`${(file.size / 1024).toFixed(1)} KB`)
                        .opacity(0.5)
                        .flexShrink(0)
                        .fontSize(0.85, rem)
                        .width("5em")

                    if (this.onDeleteNew) {
                        span("×")
                            .color("var(--quillred)")
                            .opacity(0.7)
                            .fontSize(1.2, em)
                            .fontWeight("600")
                            .flexShrink(0)
                            .cursor("pointer")
                            .padding(0.5, em)
                            .margin(-0.5, em)
                            .onTap((e) => { e?.stopPropagation(); if (window.isMobile() === true) this.onDeleteNew(index) })
                            .onClick((done, e) => { e?.stopPropagation(); if (done && window.isMobile() === false) this.onDeleteNew(index) })
                    }
                })
                .alignItems("center")
                .gap(0.5, em)
                if (this.onPreview) {
                    row.cursor("pointer")
                        .onClick((done) => { if (done) this.onPreview(file, url) })
                }
            })
        })
        .gap(1, em)
        .color("var(--text)")
        .fontSize(0.85, rem)
        .fontFamily("Arial")
    }
}
register(EventFileList)