$(() => {
    var fullPageMediaDisplayed = false;
    var selectedThumbnails = [];
    var lastKeyboardEvent = null;
    var lastSelection = null;

    function onItemSelected(mediaItem) {
        document.getElementById("pch-mediaList").classList.add("selection");
    }

    function onItemDeselected(mediaItem) {
        if (!selectedThumbnails.length)
            document.getElementById("pch-mediaList").classList.remove("selection");
    }

    function buildThumbnail(mediaItem) {
        if (mediaItem.ui)
            return mediaItem.ui;
        let checkbox = document.createElement("input");
        let img = document.createElement("img");
        let container = document.createElement("li");
        let loadingImg = document.createElement("div");
        checkbox.type = "checkbox";
        container.classList.add("pch-image");
        container.classList.add("loading");
        loadingImg.classList.add("spinner");
        loadingImg.innerHTML = "<span class='spinner-grow'></span>";
        container.dataset.md5sum = mediaItem.md5sum;
        img.loading = "lazy";
        let requestSize = mediaItem.resize(450, 450);
        img.src = `${mediaItem.thumbnail}?w=${requestSize.width}&h=${requestSize.height}&q=4`;
        img.classList.add("img-fluid");
        img.classList.add("img-thumbnail");
        img.addEventListener("load", () => {
            container.classList.remove("loading");
            container.classList.remove("spinner-grow");
        });
        container.style.width = `${requestSize.width}px`;
        container.appendChild(loadingImg);
        container.appendChild(img);
        container.appendChild(checkbox);
        let setSelectionCheckboxValue = function(media, value) {
            let checked = media.ui.checkbox.checked;
            let indexInSelection = selectedThumbnails.indexOf(media.md5sum);
            if (checked && indexInSelection < 0) {
                selectedThumbnails.push(media.md5sum);
                onItemSelected(media);
                return true;
            } else if (!checked && indexInSelection >= 0) {
                selectedThumbnails.splice(indexInSelection, 1);
                onItemDeselected(media);
                return true;
            }
            return false;
        }
        let cascadeSetSelectionCheckboxValue = function(value) {
            if (!setSelectionCheckboxValue(mediaItem, value))
                return;
            if (lastKeyboardEvent?.shiftKey && lastSelection) {
                let _lastKeyboardEvent = lastKeyboardEvent;
                lastKeyboardEvent = null;
                for (let i of MediaStorage.Instance.getMediaBetween(lastSelection, mediaItem)) {
                    if (i === mediaItem)
                        continue;
                    i.ui.checkbox.setAttribute("checked", value);
                    i.ui.checkbox.checked = value;
                    setSelectionCheckboxValue(i, value);
                }
                lastKeyboardEvent = _lastKeyboardEvent;
            }
            lastSelection = mediaItem;
            console.log(mediaItem);
        }
        container.addEventListener("click", () => {
            if (selectedThumbnails.length || lastKeyboardEvent?.ctrlKey) {
                let value = !checkbox.checked;
                checkbox.setAttribute("checked", value);
                checkbox.checked = value;
                cascadeSetSelectionCheckboxValue(value);
                return;
            }
            document.location.hash = mediaItem.md5sum;
        });
        checkbox.addEventListener("click", evt => {
            evt.stopPropagation();
        });
        checkbox.addEventListener("change", evt => {
            cascadeSetSelectionCheckboxValue(checkbox.checked);
        });
        return mediaItem.ui = {
            root: container,
            img: img,
            checkbox: checkbox
        };
    }

    function buildYear(date) {
        let result = document.createElement('h3');
        result.textContent = date.getUTCFullYear();
        return result;
    }

    function buildMonth(date) {
        let result = document.createElement('h4');
        result.textContent = date.toLocaleString('default', { month: 'long' });
        return result;
    }

    function redraw(container, media) {
        buildThumbnail(media);
        if (!media.ui)
            return;
        let yearUpdated = !container.dataset.lastItemYear || container.dataset.lastItemYear != media.date.getUTCFullYear();
        if (yearUpdated) {
            container.appendChild(buildYear(media.date));
            container.dataset.lastItemYear = media.date.getUTCFullYear();
        }
        if (yearUpdated || container.dataset.lastItemMonth === undefined || container.dataset.lastItemMonth != media.date.getUTCMonth()) {
            container.appendChild(buildMonth(media.date));
            container.dataset.lastItemMonth = media.date.getUTCMonth();
        }
        container.appendChild(media.ui.root);
    }

    MediaStorage.Instance.addEventListener("rebuildMedia", (evt) => {
        let newContainer = document.getElementById('pch-mediaList');
        newContainer.textContent = '';
        newContainer.dataset.lastItemYear = null;
        newContainer.dataset.lastItemMonth = null;
        for (let i of MediaStorage.Instance.medias)
            redraw(newContainer, i);
    });

    MediaStorage.Instance.addEventListener("newMedia", (evt) => {
        let container = document.getElementById('pch-mediaList');
        redraw(container, evt.detail);
    });

    function serializeFileSize(size) {
        let units = [ 'o', 'Ko', 'Mo', 'Go', 'To' ];
        let idx = 0;
        while (size >= 800 && idx < units.length) {
            ++idx;
            size /= 1024;
        }
        size = Math.floor(size * 100) / 100;
        return `${size} ${units[idx]}`;
    }

    function displayMeta(key, value) {
        let li = document.createElement("li");
        let type = value?.type || null;
        let val = (value?.value ? value.value : value) || null;
        if (!val)
            return null;
        if (type === 'date')
            val = val.toLocaleString();
        if (["dimension", "height", "width"].indexOf(key) >= 0)
            val += ' px';
        if (["fileSize"].indexOf(key) >= 0)
            val = serializeFileSize(val);
        let keyTranslate = {
            fileSize: "File Size",
            photochamberImport: "Photochamber Imported",
            lensModel: "Lens Model",
            exposureTimeStr: "Exposure Time"
        };
        let keyStr = keyTranslate[key] || (key[0].toUpperCase()+key.substr(1));
        li.innerText = `${keyStr}: ${val}`;
        return li;
    }

    function displayMetas(metaData) {
        let metaList = document.createElement("ul");

        metaData.libraryPath = null;

        if (metaData.exposureTime && metaData.exposureTimeStr)
            metaData.exposureTime = null;

        if (metaData.date && metaData.dateTime)
            metaData.dateTime = null;

        if (metaData.height && metaData.width) {
            metaData.dimension = { type: "string", value: `${metaData.width.value} x ${metaData.height.value}` }
            metaData.height = metaData.width = null;
        }

        for (let i of [ "date", "dimension", "height", "width", "fileSize" ]) {
            let metaItem = displayMeta(i, metaData[i]);
            metaItem && metaList.appendChild(metaItem);
            metaData[i] = null;
        }

        // FIXME sort and filter
        for (let i in metaData) {
            let metaItem = displayMeta(i, metaData[i]);
            metaItem && metaList.appendChild(metaItem);
        }
        return metaList;
    }

    function _displayMediaFullPage(fileName, imgUrl, metaData, downloadLink) {
        return new Promise(ok => {
            document.getElementById("pch-fullPagePreviewContainer").classList.add("loading");
            document.getElementById("pch-fullPageMedia-title").innerText = fileName;
            document.getElementById("pch-fullPagePreview").onceLoaded = ok;
            document.getElementById("pch-fullPagePreview").src = imgUrl;
            document.getElementById("pch-fullPageDetail").innerText = "";
            document.getElementById("pch-fullPageDetail").appendChild(displayMetas(Object.create(metaData || {})));
            if (downloadLink) {
                document.getElementById("pch-fullPageDetail-dlButton").classList.remove("hidden");
                document.getElementById("pch-fullPageDetail-dlButton").dataset["link"] = downloadLink;
            } else {
                document.getElementById("pch-fullPageDetail-dlButton").classList.add("hidden");
            }
        });
    }

    function LoadPreviousMedia() {
        let media = MediaStorage.Instance.previousMedia(fullPageMediaDisplayed);
        if (media)
            window.displayMediaFullPage(media);
    }

    function LoadNextMedia() {
        let media = MediaStorage.Instance.nextMedia(fullPageMediaDisplayed);
        if (media)
            window.displayMediaFullPage(media);
    }

    window.displayMediaFullPage = function(mediaItem) {
        document.getElementById("pch-fullPageMedia").classList.remove("hidden");
        fullPageMediaDisplayed = mediaItem;
        if (!mediaItem)
            return _displayMediaFullPage("Error", null, {}, null);
        let containerSize = document.getElementById("pch-fullPageMedia").getBoundingClientRect();
        let requestSize = mediaItem.resize(containerSize.width, containerSize.height);
        document.getElementById("pch-fullPagePreview").parentNode.style.maxWidth = "100%";
        document.getElementById("pch-fullPagePreview").parentNode.style.maxHeight = "100%";
        let meta = {
            ...mediaItem.meta,
            date: { type: 'date', value: mediaItem.date } || undefined,
            filename: mediaItem.filename ? { type: 'string', value: mediaItem.fileName } : undefined
        };
        if (document.location.hash != `#${mediaItem.md5sum}`)
            history.pushState({}, '', `#${mediaItem.md5sum}`);
        return _displayMediaFullPage(mediaItem.fileName, `${mediaItem.thumbnail}?w=${requestSize.width}&h=${requestSize.height}&q=6`, meta, mediaItem.original);
    }

    document.getElementById("pch-fullPageMedia-closeBt")
        .addEventListener("click", () => {
            document.getElementById("pch-fullPageMedia").classList.add("hidden");
            fullPageMediaDisplayed = false;
            history.pushState({}, '', '#');
        });
    document.getElementById("pch-fullPagePreview").addEventListener("load", () => {
        document.getElementById("pch-fullPagePreviewContainer").classList.remove("loading");
        let domItem = document.getElementById("pch-fullPagePreview");
        domItem.onceLoaded && domItem.onceLoaded();
        domItem.onceLoaded = null;
    });
    document.getElementById('pch-fullPageDetail-dlButton').addEventListener("click", (evt) => {
        if (!evt.target?.dataset?.link)
            return;
        let link = document.createElement('a');
        link.target='_blank';
        link.setAttribute("download", "");
        link.href = evt.target.dataset.link;
        link.click();
    });
    document.addEventListener("keyup", evt => {
        lastKeyboardEvent = evt;
    });
    document.addEventListener("keydown", evt => {
        lastKeyboardEvent = evt;
        if (!fullPageMediaDisplayed)
            return;
        if (evt.keyCode === 37 || evt.keyCode === 38)
            LoadPreviousMedia();
        else if (evt.keyCode === 39 || evt.keyCode === 40)
            LoadNextMedia();
        else {
            console.log("Unregistered key event", evt.key, evt.keyCode);
            return;
        }
        evt.preventDefault();
    });
});