oxe/src/batcher.js

A mighty tiny web components framework/library

export default {

    reads: [],
    writes: [],
    time: 1000 / 30,
    // time: 1000/60,
    pending: false,

    setup (options) {
        options = options || {};
        this.time = options.time || this.time;
    },

    tick (callback) {
        window.requestAnimationFrame(callback.bind(this, null));
    },

    // schedules a new read/write batch if one is not pending
    schedule () {
        if (this.pending) return;
        this.pending = true;
        this.tick(this.flush);
    },

    flush (time) {
        time = time || performance.now();

        let task;

        // if (data.reads === 0) {
        // 	while (task = this.reads.shift()) {
        //
        // 		if (task) {
        // 			task();
        // 			data.reads++;
        // 		}
        //
        // 		if (data.writes && data.writes === data.reads) {
        // 			data.writes = 0;
        // 			break;
        // 		}
        //
        // 		if ((performance.now() - data.time) > this.time) {
        // 			data.writes = 0;
        // 			data.time = null;
        // 			return this.tick(this.flush, data);
        // 			break;
        // 		}
        //
        // 	}
        // }
        //
        // if (data.writes === 0) {
        // 	while (task = this.writes.shift()) {
        //
        // 		if (task) {
        // 			task();
        // 			data.writes++;
        // 		}
        //
        // 		if (data.reads && data.reads === data.writes) {
        // 			data.reads = 0;
        // 			break;
        // 		}
        //
        // 		if ((performance.now() - data.time) > this.time) {
        // 			data.reads = 0;
        // 			data.time = null;
        // 			return this.tick(this.flush, data);
        // 		}
        //
        // 	}
        // }

        // while (task = this.reads.shift()) task();
        // while (task = this.writes.shift()) task();

        if (this.writes.length === 0) {
            while (task = this.reads.shift()) {

                if (task) {
                    task();
                }

                if ((performance.now() - time) > this.time) {
                    return this.tick(this.flush);
                }

            }
        }

        while (task = this.writes.shift()) {

            if (task) {
                task();
            }

            if ((performance.now() - time) > this.time) {
                return this.tick(this.flush);
            }

        }

        if (this.reads.length === 0 && this.writes.length === 0) {
            this.pending = false;
        } else if ((performance.now() - time) > this.time) {
            this.tick(this.flush);
        } else {
            this.flush(time);
        }

    },

    remove (tasks, task) {
        const index = tasks.indexOf(task);
        return !!~index && !!tasks.splice(index, 1);
    },

    clear (task) {
        return this.remove(this.reads, task) || this.remove(this.writes, task);
    },

    batch (data) {
        const self = this;

        if (!data) return;
        if (!data.read && !data.write) return;

        data.context = data.context || {};

        const read = function () {
            let result;

            if (data.read) {
                result = data.read.call(data.context, data.context);
            }

            if (data.write && result !== false) {
                const write = data.write.bind(data.context, data.context);

                self.writes.push(write);
            }

        };

        self.reads.push(read);
        self.schedule();
    }

};