/*******************************************************************************

    uBlock Origin - a browser extension to block requests.
    Copyright (C) 2014-present Raymond Hill

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see {http://www.gnu.org/licenses/}.

    Home: https://github.com/gorhill/uBlock
*/

'use strict';

/******************************************************************************/
/******************************************************************************/

(( ) => {

/******************************************************************************/

if ( typeof vAPI !== 'object' ) { return; }

const epickerId = (( ) => {
    const url = new URL(self.location.href);
    return url.searchParams.get('epid');
})();
if ( epickerId === null ) { return; }

let epickerConnectionId;
let filterHostname = '';
let filterOrigin = '';
let filterResultset = [];

/******************************************************************************/

const $id = id => document.getElementById(id);
const $stor = selector => document.querySelector(selector);
const $storAll = selector => document.querySelectorAll(selector);

/******************************************************************************/

const filterFromTextarea = function() {
    const s = taCandidate.value.trim();
    if ( s === '' ) { return ''; }
    const pos = s.indexOf('\n');
    const filter = pos === -1 ? s.trim() : s.slice(0, pos).trim();
    staticFilteringParser.analyze(filter);
    staticFilteringParser.analyzeExtra();
    return staticFilteringParser.shouldDiscard() ? '!' : filter;
};

/******************************************************************************/

const userFilterFromCandidate = function(filter) {
    if ( filter === '' || filter === '!' ) { return; }

    // Cosmetic filter?
    if ( filter.startsWith('##') ) {
        return filterHostname + filter;
    }

    // Assume net filter
    const opts = [];

    // If no domain included in filter, we need domain option
    if ( filter.startsWith('||') === false ) {
        opts.push(`domain=${filterHostname}`);
    }

    if ( filterResultset.length !== 0 ) {
        const item = filterResultset[0];
        if ( item.opts ) {
            opts.push(item.opts);
        }
    }

    if ( opts.length ) {
        filter += '$' + opts.join(',');
    }

    return filter;
};

/******************************************************************************/

const candidateFromFilterChoice = function(filterChoice) {
    let { slot, filters } = filterChoice;
    let filter = filters[slot];

    // https://github.com/uBlockOrigin/uBlock-issues/issues/47
    for ( const elem of $storAll('#candidateFilters li') ) {
        elem.classList.remove('active');
    }

    if ( filter === undefined ) { return ''; }

    // For net filters there no such thing as a path
    if ( filter.startsWith('##') === false ) {
        $stor(`#netFilters li:nth-of-type(${slot+1})`)
            .classList.add('active');
        return filter;
    }

    // At this point, we have a cosmetic filter

    $stor(`#cosmeticFilters li:nth-of-type(${slot+1})`)
        .classList.add('active');

    // Modifier means "target broadly". Hence:
    // - Do not compute exact path.
    // - Discard narrowing directives.
    // - Remove the id if one or more classes exist
    //   TODO: should remove tag name too? ¯\_(ツ)_/¯
    if ( filterChoice.modifier ) {
        filter = filter.replace(/:nth-of-type\(\d+\)/, '');
        // https://github.com/uBlockOrigin/uBlock-issues/issues/162
        //   Mind escaped periods: they do not denote a class identifier.
        if ( filter.charAt(2) === '#' ) {
            const pos = filter.search(/[^\\]\./);
            if ( pos !== -1 ) {
                filter = '##' + filter.slice(pos + 1);
            }
        }
        return filter;
    }

    // Return path: the target element, then all siblings prepended
    let selector = '', joiner = '';
    for ( ; slot < filters.length; slot++ ) {
        filter = filters[slot];
        // Remove all classes when an id exists.
        // https://github.com/uBlockOrigin/uBlock-issues/issues/162
        //   Mind escaped periods: they do not denote a class identifier.
        if ( filter.charAt(2) === '#' ) {
            filter = filter.replace(/([^\\])\..+$/, '$1');
        }
        selector = filter.slice(2) + joiner + selector;
        // Stop at any element with an id: these are unique in a web page
        if ( filter.startsWith('###') ) { break; }
        // Stop if current selector matches only one element on the page
        if ( document.querySelectorAll(selector).length === 1 ) { break; }
        joiner = ' > ';
    }

    // https://github.com/gorhill/uBlock/issues/2519
    // https://github.com/uBlockOrigin/uBlock-issues/issues/17
    if (
        slot === filters.length &&
        selector.startsWith('body > ') === false &&
        document.querySelectorAll(selector).length > 1
    ) {
        selector = 'body > ' + selector;
    }

    return '##' + selector;
};

/******************************************************************************/

const onCandidateChanged = function() {
    const filter = filterFromTextarea();
    const bad = filter === '!';
    $stor('section').classList.toggle('invalidFilter', bad);
    $id('create').disabled = bad;
    if ( bad ) {
        $id('resultsetCount').textContent = 'E';
        $id('create').setAttribute('disabled', '');
    }
    vAPI.MessagingConnection.sendTo(epickerConnectionId, {
        what: 'dialogSetFilter',
        filter,
        compiled: filter.startsWith('##')
            ? staticFilteringParser.result.compiled
            : undefined,
    });
};

/******************************************************************************/

const onPreviewClicked = function() {
    const state = pickerBody.classList.toggle('preview');
    vAPI.MessagingConnection.sendTo(epickerConnectionId, {
        what: 'dialogPreview',
        state,
    });
};

/******************************************************************************/

const onCreateClicked = function() {
    const candidate = filterFromTextarea();
    const filter = userFilterFromCandidate(candidate);
    if ( filter !== undefined ) {
        vAPI.messaging.send('elementPicker', {
            what: 'createUserFilter',
            autoComment: true,
            filters: filter,
            origin: filterOrigin,
            pageDomain: filterHostname,
            killCache: /^#[$?]?#/.test(candidate) === false,
        });
    }
    vAPI.MessagingConnection.sendTo(epickerConnectionId, {
        what: 'dialogCreate',
        filter: candidate,
        compiled: candidate.startsWith('##')
            ? staticFilteringParser.result.compiled
            : undefined,
    });
};

/******************************************************************************/

const onPickClicked = function(ev) {
    if (
        (ev instanceof MouseEvent) &&
        (ev.type === 'mousedown') &&
        (ev.which !== 1 || ev.target !== document.body)
    ) {
        return;
    }
    pickerBody.classList.remove('paused');
    vAPI.MessagingConnection.sendTo(epickerConnectionId, {
        what: 'dialogPick'
    });
};

/******************************************************************************/

const onQuitClicked = function() {
    vAPI.MessagingConnection.sendTo(epickerConnectionId, {
        what: 'dialogQuit'
    });
};

/******************************************************************************/

const onCandidateClicked = function(ev) {
    let li = ev.target.closest('li');
    const ul = li.closest('.changeFilter');
    if ( ul === null ) { return; }
    const choice = {
        filters: Array.from(ul.querySelectorAll('li')).map(a => a.textContent),
        slot: 0,
        modifier: ev.ctrlKey || ev.metaKey
    };
    while ( li.previousElementSibling !== null ) {
        li = li.previousElementSibling;
        choice.slot += 1;
    }
    taCandidate.value = candidateFromFilterChoice(choice);
    onCandidateChanged();
};

/******************************************************************************/

const onKeyPressed = function(ev) {
    // Esc
    if ( ev.key === 'Escape' || ev.which === 27 ) {
        onQuitClicked();
        return;
    }
};

/******************************************************************************/

const onStartMoving = (( ) => {
    let mx0 = 0, my0 = 0;
    let mx1 = 0, my1 = 0;
    let r0 = 0, b0 = 0;
    let rMax = 0, bMax = 0;
    let timer;

    const move = ( ) => {
        timer = undefined;
        let r1 = Math.min(Math.max(r0 - mx1 + mx0, 4), rMax);
        let b1 = Math.min(Math.max(b0 - my1 + my0, 4), bMax);
        dialog.style.setProperty('right', `${r1}px`, 'important');
        dialog.style.setProperty('bottom', `${b1}px`, 'important');
    };

    const moveAsync = ev => {
        if ( ev.isTrusted === false ) { return; }
        eatEvent(ev);
        if ( timer !== undefined ) { return; }
        mx1 = ev.pageX;
        my1 = ev.pageY;
        timer = self.requestAnimationFrame(move);
    };

    const stop = ev => {
        if ( ev.isTrusted === false ) { return; }
        if ( dialog.classList.contains('moving') === false ) { return; }
        dialog.classList.remove('moving');
        self.removeEventListener('mousemove', moveAsync, { capture: true });
        self.removeEventListener('mouseup', stop, { capture: true, once: true });
        eatEvent(ev);
    };

    return function(ev) {
        if ( ev.isTrusted === false ) { return; }
        const target = dialog.querySelector('#toolbar');
        if ( ev.target !== target ) { return; }
        if ( dialog.classList.contains('moving') ) { return; }
        mx0 = ev.pageX; my0 = ev.pageY;
        const style = self.getComputedStyle(dialog);
        r0 = parseInt(style.right, 10);
        b0 = parseInt(style.bottom, 10);
        const rect = dialog.getBoundingClientRect();
        rMax = pickerBody.clientWidth - 4 - rect.width ;
        bMax = pickerBody.clientHeight - 4 - rect.height;
        dialog.classList.add('moving');
        self.addEventListener('mousemove', moveAsync, { capture: true });
        self.addEventListener('mouseup', stop, { capture: true, once: true });
        eatEvent(ev);
    };
})();

/******************************************************************************/

const eatEvent = function(ev) {
    ev.stopPropagation();
    ev.preventDefault();
};

/******************************************************************************/

const showDialog = function(details) {
    pickerBody.classList.add('paused');

    const { netFilters, cosmeticFilters, filter, options } = details;

    // https://github.com/gorhill/uBlock/issues/738
    //   Trim dots.
    filterHostname = details.hostname;
    if ( filterHostname.slice(-1) === '.' ) {
        filterHostname = filterHostname.slice(0, -1);
    }
    filterOrigin = details.origin;

    // Create lists of candidate filters
    const populate = function(src, des) {
        const root = dialog.querySelector(des);
        const ul = root.querySelector('ul');
        while ( ul.firstChild !== null ) {
            ul.firstChild.remove();
        }
        for ( let i = 0; i < src.length; i++ ) {
            const li = document.createElement('li');
            li.textContent = src[i];
            ul.appendChild(li);
        }
        if ( src.length !== 0 ) {
            root.style.removeProperty('display');
        } else {
            root.style.setProperty('display', 'none', 'important');
        }
    };

    populate(netFilters, '#netFilters');
    populate(cosmeticFilters, '#cosmeticFilters');

    dialog.querySelector('ul').style.display =
        netFilters.length || cosmeticFilters.length ? '' : 'none';
    dialog.querySelector('#create').disabled = true;

    // Auto-select a candidate filter

    // 2020-09-01:
    //   In Firefox, `details instanceof Object` resolves to `false` despite
    //   `details` being a valid object. Consequently, falling back to use
    //   `typeof details`.
    //   This is an issue which surfaced when the element picker code was
    //   revisited to isolate the picker dialog DOM from the page DOM.
    if ( typeof filter !== 'object' || filter === null ) {
        taCandidate.value = '';
        return;
    }

    const filterChoice = {
        filters: filter.filters,
        slot: filter.slot,
        modifier: options.modifier || false
    };

    taCandidate.value = candidateFromFilterChoice(filterChoice);
    onCandidateChanged();
};

/******************************************************************************/

// Let's have the element picker code flushed from memory when no longer
// in use: to ensure this, release all local references.

const stopPicker = function() {
    vAPI.shutdown.remove(stopPicker);
};

/******************************************************************************/

const pickerBody = document.body;
const dialog = $stor('aside');
const taCandidate = $stor('textarea');
let staticFilteringParser;

/******************************************************************************/

const startDialog = function() {
    dialog.addEventListener('click', eatEvent);
    taCandidate.addEventListener('input', onCandidateChanged);
    $stor('body').addEventListener('mousedown', onPickClicked);
    $id('preview').addEventListener('click', onPreviewClicked);
    $id('create').addEventListener('click', onCreateClicked);
    $id('pick').addEventListener('click', onPickClicked);
    $id('quit').addEventListener('click', onQuitClicked);
    $id('candidateFilters').addEventListener('click', onCandidateClicked);
    $id('toolbar').addEventListener('mousedown', onStartMoving);
    self.addEventListener('keydown', onKeyPressed, true);
    staticFilteringParser = new vAPI.StaticFilteringParser({ interactive: true });
};

/******************************************************************************/

const onPickerMessage = function(msg) {
    switch ( msg.what ) {
    case 'showDialog':
        showDialog(msg);
        break;
    case 'filterResultset':
        filterResultset = msg.resultset;
        $id('resultsetCount').textContent = filterResultset.length;
        if ( filterResultset.length !== 0 ) {
            $id('create').removeAttribute('disabled');
        } else {
            $id('create').setAttribute('disabled', '');
        }
        break;
    }
};

/******************************************************************************/

const onConnectionMessage = function(msg) {
    switch ( msg.what ) {
    case 'connectionBroken':
        stopPicker();
        break;
    case 'connectionMessage':
        onPickerMessage(msg.payload);
        break;
    case 'connectionAccepted':
        epickerConnectionId = msg.id;
        startDialog();
        vAPI.MessagingConnection.sendTo(epickerConnectionId, {
            what: 'dialogInit',
        });
        break;
    }
};

vAPI.MessagingConnection.connectTo(
    `epickerDialog-${epickerId}`,
    `epicker-${epickerId}`,
    onConnectionMessage
);

/******************************************************************************/

})();








/*******************************************************************************

    DO NOT:
    - Remove the following code
    - Add code beyond the following code
    Reason:
    - https://github.com/gorhill/uBlock/pull/3721
    - uBO never uses the return value from injected content scripts

**/

void 0;