import ngModule from '../../module';

export default class ModelProxy {
    constructor() {
        this._data = [];
        this.resetChanges();
    }

    get orgData() {
        return this._orgData;
    }

    set orgData(value) {
        this._orgData = value;
        // this._data.splice(0, this._data.length);

        if (this.Row) {
            this._data = [];

            for (let i = 0; i < value.length; i++) {
                let row = new this.Row(value[i], i);
                this._data.push(row);
            }
        } else
            this._data = value;

        this.resetChanges();
    }

    get data() {
        return this._data;
    }

    set data(value) {}

    get fields() {
        return this._fields;
    }

    set fields(value) {
        this._fields = value;

        let Row = function(data, index) {
            this.$data = data;
            this.$index = index;
            this.$oldData = null;
            this.$isNew = false;
        };

        for (let prop of value) {
            Object.defineProperty(Row.prototype, prop, {
                enumerable: true,
                configurable: false,
                set: function(value) {
                    if (!this.$isNew) {
                        if (!this.$oldData)
                            this.$oldData = {};
                        if (!this.$oldData[prop])
                            this.$oldData[prop] = this.$data[prop];
                    }

                    this.$data[prop] = value;
                },
                get: function() {
                    return this.$data[prop];
                }
            });
        }

        this.Row = Row;
    }

    remove(index) {
        let data = this._data;

        let item;
        [item] = data.splice(index, 1);

        for (let i = index; i < data.length; i++)
            data[i].$index = i;

        if (!item.$isNew)
            this.removed.push(item);
    }

    insert(data) {
        data = Object.assign(data || {}, this.link);
        let newRow = new this.Row(data, this._data.length);
        newRow.$isNew = true;
        return this._data.push(newRow);
    }

    resetChanges() {
        this.removed = [];

        for (let row of this._data) {
            row.$oldData = null;
            row.$isNew = false;
        }
    }

    undoChanges() {
        let data = this._data;

        for (let i = 0; i < data.length; i++) {
            let row = data[i];

            if (row.$oldData)
                Object.assign(row.$data, row.$oldData);
            if (row.$isNew)
                data.splice(i--, 1);
        }

        for (let row of this.removed)
            data.splice(row.$index, 0, row);

        this.resetChanges();
    }

    dataChanged() {
        if (this.onDataChange)
            this.onDataChange();
    }
}

ngModule.component('vnModelProxy', {
    controller: ModelProxy,
    bindings: {
        orgData: '<?',
        data: '=?',
        fields: '<?',
        link: '<?',
        onDataChange: '&?'
    }
});