/////////////////////////////////////

const UUID = function() {
    let allowedIdChars = "0123456789abcdef";

    // fallback in case we cannot crypto
    const notUniqueId = (t = 16) => {
        let out = "";
        for (let i = 0; i < t; i++) {
            out += allowedIdChars[(Math.random() * allowedIdChars.length + Math.floor(performance.now())) % allowedIdChars.length];
        }
        return out;
    }

    // from https://github.com/ai/nanoid/blob/main/nanoid.js
    const uniqueId = (t = 16) => {
        const indices = crypto.getRandomValues(new Uint8Array(t));
        let out = "";
        for (var i = 0; i < t; i++) {
            out += allowedIdChars[indices[i] % allowedIdChars.length];
        }
        return out;
    }

    this.getUuid = () => {
        return typeof crypto === 'object' && typeof crypto.getRandomValues === 'function' ?
            uniqueId() : notUniqueId();
    }
}

const uuid = new UUID();

const getUuid = () => {
    return uuid.getUuid();
}

const makeEven = (n) => {
    const nr = Math.round(n);
    return nr - nr % 2;
}

    const getMix = (before_s, after_s, time_s, clamp = true) => {
        const diff = after_s - before_s;
        const travel = time_s - before_s;
        if (diff === 0 || travel === 0) {
            return 0;
        } else if (clamp) {
            return Math.min(Math.max(travel / diff));
        } else {
            return travel / diff;
        }
    }
    const mix = (a, b, m, t) => {
        if (Math.abs(a - b) < t) {
            return b;
        } else {
            return a * (1.0 - m) + b * m;
        }
    };

const mixObject = (a, b, m) => {
    const out = JSON.parse(JSON.stringify(a));
    const a_keys = Object.keys(a);
    const b_keys = Object.keys(b);
    let keys = [...new Set([...a_keys, ...b_keys])];
    keys.forEach((key) => {
		if (!a.hasOwnProperty(key)) {
			out[key] = b[key];
		} else if (!b.hasOwnProperty(key)) {
			out[key] = a[key];
		} else {
	        if (typeof a[key] === 'object') {
	            out[key] = mixObject(a[key], b[key], m);
	        } else if (typeof a[key] === 'number') {
	            out[key] = a[key] * (1.0 - m) + b[key] * m;
	        } else {
	            out[key] = b[key];
	        }
	}
    });
    return out;
};

/////////////////////////////////////

const htmlToElement = (html) => {
    var template = document.createElement('template');
    html = html.trim(); // Never return a text node of whitespace as the result
    template.innerHTML = html;
    return template.content.firstChild;
}

/////////////////////////////////////

// download(textData, 'lol.txt', 'text/plain');
// download(jsonData, 'lol.json', 'application/json');
function downloadFile(content, fileName, contentType) {
    var a = document.createElement("a");
    var file = new Blob([content], {
        type: contentType
    });
    a.href = URL.createObjectURL(file);
    a.download = fileName;
    a.click();
}

function uploadFile(expectedType = 'application/json') {
    return new Promise((resolve, reject) => {
        var input = document.createElement('input');
        input.type = 'file';
        input.addEventListener('change', () => {
            let json;
            let files = input.files;

            if (files.length == 0) return;

            const file = files[0];
            console.log('file', file);

            let reader = new FileReader();

            if (expectedType === 'application/zip' || file.type === 'application/zip') {
                reader.onload = (e) => {
                    const f = e.target.result;
                    console.log(e, file.name, file.size, file.type, f);
                    resolve({
                        name: file.name,
                        size: file.size,
                        type: file.type,
                        arrayBuffer: f,
                    });
                };

                reader.onerror = (e) => reject(e.target.error.name);

                reader.readAsArrayBuffer(file);
            } else if (expectedType === 'application/json') {
                reader.onload = (e) => {
                    console.log(e);
                    const f = e.target.result;

                    // This is a regular expression to identify carriage
                    // Returns and line breaks
                    //const lines = file.split(/\r\n|\n/);
                    if (file.type === expectedType) {
                        try {
                            json = JSON.parse(f);
                            resolve(json);
                        } catch (e) {
                            reject("Caught: " + e.message)
                        }
                    }
                };

                reader.onerror = (e) => reject(e.target.error.name);

                reader.readAsText(file);
            } else if (expectedType.indexOf('font') >= 0) {
                console.log('expect font');
                reader.onload = (e) => {
                    console.log(e);
                    const f = e.target.result;
                    if (file.type.indexOf('font') >= 0) {
                        console.log('is font');
                        //var uint8View = new Uint8Array(f);
                        //console.log('trying to save the font file, file, uint8View', file, uint8View);
                        //FS.createDataFile(config.fs.idbfsFontDir, file.name, uint8View, true, true);
                        resolve({
                            name: file.name,
                            size: file.size,
                            type: file.type,
                            arrayBuffer: f
                        });
                    } else {
                        const extension = file.name.split('.').reverse().shift()
                        const fileType = `font/${extension}`;
                        if(confirm(`${file.name} has type ${file.type} instead of the expected ${fileType}. are you sure this is a font?`)) {
                            const outputFile = {
                                isFont: true,
                                name: file.name,
                                size: file.size,
                                type: file.type,
                                arrayBuffer: f
                            };
                            console.log({outputFile});
                            resolve(outputFile);
                        } else {
                            reject('not a font');
                        }
                    }
                };

                reader.onerror = (e) => reject(e.target.error.name);

                reader.readAsArrayBuffer(file);
            } else {
                alert(`unknown filetype ${file.type}, what are you uploading?`);
                resolve(false);
            }

        });
        input.click();

        //var a = document.createElement('a');
        //a.onclick = () => {
        //var e = document.createEvent('MouseEvents');
        //e.initEvent('click', true, false);
        //input.dispatchEvent(e);
        //};
        //a.click();
    });
}

const makeDraggable = (elmnt, draggedCallback = false) => {
    var pos1 = 0,
        pos2 = 0,
        pos3 = 0,
        pos4 = 0;
    if (elmnt.querySelector('.header .move')) {
        // if present, the header is where you move the DIV from:
        elmnt.querySelector('.header .move').onmousedown = dragMouseDown;
    } else {
        // otherwise, move the DIV from anywhere inside the DIV:
        elmnt.onmousedown = dragMouseDown;
    }

    function dragMouseDown(e) {
        e = e || window.event;
        e.preventDefault();
        // get the mouse cursor position at startup:
        pos3 = e.clientX;
        pos4 = e.clientY;
        document.onmouseup = closeDragElement;
        // call a function whenever the cursor moves:
        document.onmousemove = elementDrag;
    }

    function elementDrag(e) {
        e = e || window.event;
        e.preventDefault();
        // calculate the new cursor position:
        pos1 = pos3 - e.clientX;
        pos2 = pos4 - e.clientY;
        pos3 = e.clientX;
        pos4 = e.clientY;
        // set the element's new position:
        elmnt.style.top = (elmnt.offsetTop - pos2) + "px";
        elmnt.style.left = (elmnt.offsetLeft - pos1) + "px";
    }

    function closeDragElement() {
        // stop moving when mouse button is released:
        document.onmouseup = null;
        document.onmousemove = null;
        if (typeof draggedCallback === 'function') {
            draggedCallback();
        }
    }
}


const cyrb53 = (str, seed = 0) => {
    let h1 = 0xdeadbeef ^ seed,
        h2 = 0x41c6ce57 ^ seed;
    for (let i = 0, ch; i < str.length; i++) {
        ch = str.charCodeAt(i);
        h1 = Math.imul(h1 ^ ch, 2654435761);
        h2 = Math.imul(h2 ^ ch, 1597334677);
    }
    h1 = Math.imul(h1 ^ (h1 >>> 16), 2246822507);
    h1 ^= Math.imul(h2 ^ (h2 >>> 13), 3266489909);
    h2 = Math.imul(h2 ^ (h2 >>> 16), 2246822507);
    h2 ^= Math.imul(h1 ^ (h1 >>> 13), 3266489909);

    return 4294967296 * (2097151 & h2) + (h1 >>> 0);
};

const hashFromString = (str, prefix = 'hash') => {
    return `${prefix}${cyrb53(str)}`;
};

function getBaseName(filePath) {
    return filePath.substring(filePath.lastIndexOf('/') + 1, filePath.lastIndexOf('.'))
}

function verifyVariableTimeProject(vt_project) {
    const exampleProject = {
        projectId: 'exampleProject',
        variable_time_version: VARIABLE_TIME_VERSION,
        theatre: 'complete theatre saveFile',
        layerOrder: ['layer-0', 'layer-4', 'layer-2'],
    };
    if (!vt_project) {
        console.error('Utils::verifyVariableTimeProject::couldNotVerify',
            'project equals false',
            'this is what we received',
            vt_project,
            'compare to following example',
            exampleProject);
        return false;
    }
    if (typeof vt_project === 'string') {
        console.error('Utils::verifyVariableTimeProject::couldNotVerify',
            'project is a string, please first parse json ',
            'this is what we received',
            vt_project,
            'compare to following example',
            exampleProject);
        return false;
        // do not allow strings
        //try {
            //vt_project = JSON.parse(vt_project);
        //} catch (e) {
            //console.error('Utils::verifyVariableTimeProject::couldNotVerify',
                //'project is a string,
                //but could not parse json ',
                //'this is what we received',
                //vt_project,
                //'compare to following example',
                //exampleProject);
            //return false;
        //}
    }
    if (typeof vt_project !== 'object') {
        console.error('Utils::verifyVariableTimeProject::couldNotVerify',
            'project is not an object',
            'this is what we received',
            vt_project,
            'compare to following example',
            exampleProject);
        return false;
    }
    const exampleKeys = Object.keys(exampleProject);
    for (let i = 0; i < exampleKeys.length; i++) {
        if (!vt_project.hasOwnProperty(exampleKeys[i])) {
            console.error('Utils::verifyVariableTimeProject::couldNotVerify',
                `${exampleKeys[i]} missing`,
                'this is what we received',
                vt_project,
                'compare to following example',
                exampleProject);
            return false;
        }
    }
    return true;
}

function clone(a) {
    return JSON.parse(JSON.stringify(a));
};

function getParents(elem, until = null) {
    const parents = [];
    let done = false;
    while (!done) {
        elem = elem.parentNode;
        if (elem === until) {
            done = true;
        } else if (elem === null) {
            // until is not a parent
            return null;
        } else {
            parents.push(elem);
        }
    }
    return parents;
}

function arraysEqual(a, b, sortingMatters = false) {
    if (a === b) return true;
    if (a == null || b == null) return false;
    if (a.length !== b.length) return false;
    if (!Array.isArray(a) || !Array.isArray(b)) return false;

    let _a = sortingMatters ? a : a.toSorted();
    let _b = sortingMatters ? b : b.toSorted();

    for (var i = 0; i < _a.length; ++i) {
        if (_a[i] !== _b[i]) return false;
    }
    return true;
}

const mapValue = (value, low1, high1, low2, high2, clamp=false) => {
    const mapped = low2 + (high2 - low2) * (value - low1) / (high1 - low1);
    return clamp ? Math.min(high2 > low2 ? high2 : low2, Math.max(low2 < high2 ? low2 : high2, mapped)) : mapped;
}

const isMobile = () => {
    if (/Android|webOS|iPhone|iPad|iPod|BlackBerry|IEMobile|Opera Mini/i.test(navigator.userAgent)) {
        return true;
    } else if (navigator.maxTouchPoints && navigator.maxTouchPoints > 2 && /MacIntel/.test(navigator.platform)) {
        return true;
    }
    return false;
};

/////////////////////////////////////

export {
    getUuid,
    htmlToElement,
    downloadFile,
    uploadFile,
    makeDraggable,
    getBaseName,
    hashFromString,
    verifyVariableTimeProject,
    makeEven,
    mix,
    getMix,
	mixObject,
    clone,
    getParents,
    arraysEqual,
    mapValue,
}