// Simple Dropdown/Autocomplete with single/multiple selection and easy customisation via CSS modules
// Version 2021-09-18
// License: LGPLv3.0+
// (c) Vitaliy Filippov 2019+

import React from 'react';
import PropTypes from 'prop-types';

import autocomplete_css from './autocomplete.css';
import PickerMenu from './PickerMenu.js';

export default class Selectbox extends React.PureComponent
{
    static propTypes = {
        // multi-select
        multiple: PropTypes.bool,
        // make text input readonly (disable user input). still allows value change
        readOnly: PropTypes.bool,
        // show "clear" icon (cross)
        allowClear: PropTypes.bool,
        // select/autocomplete options - either an array of objects, or a { [string]: string } object
        source: PropTypes.oneOfType([PropTypes.array, PropTypes.object]),
        // current value
        value: PropTypes.oneOfType([PropTypes.array, PropTypes.string, PropTypes.number]),
        // change callback
        onChange: PropTypes.func,
        // do not hide suggestion list on change
        keepFocusOnChange: PropTypes.bool,
        // item name key - default "name"
        labelKey: PropTypes.oneOfType([PropTypes.string, PropTypes.number]),
        // item text key - default "name"
        textKey: PropTypes.oneOfType([PropTypes.string, PropTypes.number]),
        // item id key - default "id"
        valueKey: PropTypes.oneOfType([PropTypes.string, PropTypes.number]),
        // item "disabled" key - default none
        disabledKey: PropTypes.oneOfType([PropTypes.string, PropTypes.number]),
        // item CSS class key - default none
        classKey: PropTypes.oneOfType([PropTypes.string, PropTypes.number]),
        // automatically filter autocomplete options based on user input if `true`
        suggestionMatch: PropTypes.oneOfType([PropTypes.bool, PropTypes.oneOf(['disabled'])]),
        // additional message to display below autocomplete options (arbitrary HTML, for example "...")
        suggestionMsg: PropTypes.any,
        // disable the whole input
        disabled: PropTypes.bool,
        // placeholder to display when the input is empty
        placeholder: PropTypes.string,
        // minimum suggestion list width in pixels
        minWidth: PropTypes.number,
        // change theme (CSS module) for this input
        theme: PropTypes.object,
        // additional CSS class name for the input
        className: PropTypes.string,
        // additional CSS styles for the input
        style: PropTypes.object,
        // additional event listener for onFocus
        onFocus: PropTypes.func,
        // additional event listener for onBlur
        onBlur: PropTypes.func,
        // additional event listener for user text input
        onQueryChange: PropTypes.func,
    }

    state = {
        shown: false,
        query: null,
        inputWidth: 20,
    }

    setQuery = (ev) =>
    {
        const query = ev.target.value;
        this.setState({ query });
        const f = this.props.onQueryChange;
        if (f)
        {
            f(query);
        }
        if (!query.length && !this.props.multiple && this.props.allowClear)
        {
            this.clear();
        }
    }

    clear = () =>
    {
        this.setState({ query: null });
        const f = this.props.onChange;
        f && f(null);
    }

    removeValue = (ev) =>
    {
        const n = ev.currentTarget.getAttribute('data-n');
        if (n != null)
        {
            const v = [ ...this.props.value ];
            v.splice(n, 1);
            const f = this.props.onChange;
            f && f(v);
        }
    }

    onSelectItem = (item) =>
    {
        this.setState({ query: null });
        if (this.props.keepFocusOnChange === false ||
            this.props.keepFocusOnChange == null && !this.props.multiple)
        {
            this.picker.blur();
        }
        const sel = item[this.props.valueKey||'id'];
        if (this.props.disabledKey && item[this.props.disabledKey])
        {
            // item is disabled
            return;
        }
        let value = sel;
        if (this.props.multiple)
        {
            const already = (this.props.value||[]).indexOf(sel);
            if (already < 0)
            {
                // add
                value = [ ...(this.props.value||[]), sel ];
            }
            else
            {
                // remove
                value = [ ...this.props.value ];
                value.splice(already, 1);
            }
        }
        const f = this.props.onChange;
        f && f(value);
    }

    focusInput = () =>
    {
        if (!this.props.disabled)
        {
            this.input.focus();
        }
    }

    onFocus = () =>
    {
        if (this.props.disabled)
        {
            return;
        }
        if (!this.props.multiple && this.picker.state.active === null)
        {
            const v = this.props.value, vk = this.props.valueKey||'id';
            for (let i = 0; i < this.filtered_items.length; i++)
            {
                if (v == this.filtered_items[i][vk])
                {
                    this.picker.setState({ active: i });
                    break;
                }
            }
        }
        this.picker.focus();
        const f = this.props.onFocus;
        f && f();
    }

    onBlur = () =>
    {
        this.picker.blur();
        const f = this.props.onBlur;
        f && f();
        if (!this.props.multiple && !this.props.allowClear && !this.input.value.length)
        {
            this.setState({ query: null });
        }
    }

    renderInput = (p) =>
    {
        const theme = this.props.theme || autocomplete_css;
        const value = this.state.query == null
            ? (this.props.multiple ? '' : this.item_hash[this.props.value]||'')
            : this.state.query;
        const input = <input
            readOnly={this.props.readOnly}
            disabled={this.props.disabled}
            placeholder={!this.props.multiple || !this.props.value || !this.props.value.length ? this.props.placeholder : undefined}
            ref={this.setInput}
            className={theme.inputElement}
            style={this.props.multiple ? { width: this.state.inputWidth+'px' } : undefined}
            onFocus={this.onFocus}
            onBlur={this.onBlur}
            value={value}
            onChange={this.setQuery}
            onKeyDown={p.onKeyDown}
        />;
        return (<div ref={p.ref}
            className={theme.input +
                (p.focused ? ' '+(theme.focused||'') : '') +
                (this.props.disabled ? ' '+(theme.disabled||'') : '') +
                (this.props.readOnly ? ' '+(theme.readonly||'') : '') +
                (this.props.multiple
                    ? ' '+(theme.multiple||'')
                    : (this.props.allowClear ? ' '+(theme.withClear||'') : '')) +
                (this.props.className ? ' '+this.props.className : '')}
            style={this.props.style}
            onClick={this.focusInput}>
            {this.props.multiple
                ? <div className={theme.values}>
                    <span className={theme.inputElement+' '+theme.sizer} ref={this.setSizer}>
                        {this.props.multiple && (!this.props.value || !this.props.value.length) && value === ''
                            ? (this.props.placeholder || '') : value}
                    </span>
                    {(this.props.value||[]).map((id, idx) => <span className={theme.value} key={idx}>
                        {this.props.allowClear && !this.props.disabled
                            ? <span data-n={idx} className={theme.clearValue} onClick={this.removeValue}></span>
                            : null}
                        {this.item_hash[id]}
                    </span>)}
                    {input}
                </div>
                : input}
            {this.props.allowClear && !this.props.multiple && this.props.value != null
                ? <div className={theme.clear} onClick={this.clear}></div>
                : null}
        </div>);
    }

    setSizer = (e) =>
    {
        this.sizer = e;
    }

    setPicker = (e) =>
    {
        this.picker = e;
    }

    setInput = (e) =>
    {
        this.input = e;
    }

    render()
    {
        if (!this.prevProps || this.props.source != this.prevProps.source)
        {
            if (!this.props.source)
            {
                this.items = [];
                this.item_hash = {};
            }
            else if (this.props.source instanceof Array)
            {
                this.items = this.props.source;
                this.item_hash = this.items.reduce((a, c) => { a[c[this.props.valueKey||'id']] = c[this.props.textKey||'name']; return a; }, {});
            }
            else
            {
                this.items = Object.keys(this.props.source).map(id => ({ id, name: this.props.source[id] }));
                this.item_hash = this.props.source;
            }
        }
        if (!this.prevProps || this.props.source != this.prevProps.source ||
            this.props.suggestionMatch != this.prevProps.suggestionMatch ||
            this.state.query != this.prevState.query)
        {
            if (!this.props.suggestionMatch || this.props.suggestionMatch == 'disabled' || !this.state.query)
            {
                this.filtered_items = this.items;
            }
            else
            {
                const n = this.props.textKey||'name';
                const q = this.state.query.toLowerCase();
                this.filtered_items = this.items.filter(e => e[n].toLowerCase().indexOf(q) >= 0);
            }
        }
        this.prevProps = this.props;
        this.prevState = this.state;
        return (<PickerMenu
            ref={this.setPicker}
            minWidth={this.props.minWidth}
            autoHide={true}
            keepOnClick={this.props.keepFocusOnChange === true ||
                this.props.keepFocusOnChange == null && this.props.multiple}
            renderInput={this.renderInput}
            items={this.filtered_items}
            labelKey={this.props.labelKey||'name'}
            disabledKey={this.props.disabledKey}
            classKey={this.props.classKey}
            afterItems={this.props.suggestionMsg}
            onSelectItem={this.onSelectItem}
            usePortal={this.props.usePortal}
        />);
    }

    componentDidUpdate()
    {
        if (this.sizer)
        {
            this.setState({ inputWidth: this.sizer.offsetWidth });
        }
    }

    componentDidMount()
    {
        this.componentDidUpdate();
    }
}