import React, {useState} from "react";
import {Link, Route, Routes, useLocation, useNavigate} from "react-router";
import {FilesSearchView, SearchViewButton} from "./Files";
import {useLatestRequest, usePages, useSearchChannels, useSearchDate, useSearchDeep, useSearchFilter} from "../hooks/customHooks";
import {ShortcutHint} from "./ShortcutHint";
import {ZimSearchView} from "./Zim";
import {MapSearchView} from "./MapSearchView";
import {searchEstimateFiles, searchEstimateMap, searchEstimateOthers, searchEstimateZims, searchSuggestions} from "../api";
import {filterToMimetypes, fuzzyMatch, normalizeEstimate, SearchResultsInput, TabLinks} from "./Common";
import _ from "lodash";
import {TagsContext} from "../Tags";
import {Accordion, Header, Icon, Label, Loading, Panel, Stack} from "./ui";
import {QueryContext} from "../contexts/contexts";
import {KeyboardShortcutsContext} from "../contexts/KeyboardShortcutsContext";

const SUGGESTED_APPS = [
    {location: '/admin', title: 'Downloads', description: 'View and control your downloads'},
    {location: '/admin/settings', title: 'Hotspot', description: 'Control your hotspot'},
    {location: '/admin/settings', title: 'Restart', description: 'Restart your WROLPi'},
    {location: '/admin/settings', title: 'Settings', description: 'View and modify your settings'},
    {location: '/admin/settings', title: 'Shutdown', description: 'Shutdown your WROLPi'},
    {location: '/admin/status', title: 'Status', description: 'View the status of this WROLPi server'},
    {location: '/admin/wrol', title: 'WROL Mode', description: 'Enable or disable WROL Mode'},
    {location: '/archives', title: 'Archives', description: 'View your Archives'},
    {location: '/archives/domains', title: 'Domains', description: 'View the domains of your Archives'},
    {location: '/files', title: 'Files', description: 'View your files'},
    {location: '/help', title: 'Help', description: 'Help documents for WROLPi'},
    {location: '/inventory', title: 'Inventory', description: 'Track and organize your food storage'},
    {location: '/map', title: 'Map', description: 'View your Map'},
    {location: '/map/manage', title: 'Manage Map', description: 'Manage your Map'},
    {location: '/more/calculators?calc=otp', title: 'One Time Pad', description: 'Encrypt and Decrypt messages'},
    {location: '/more/statistics', title: 'Statistics', description: 'View the statistics of your WROLPi'},
    {
        location: '/more/calculators?calc=vin',
        title: 'Vin Decoder',
        description: 'Decode and analyze vehicle VIN numbers'
    },
    {location: '/videos', title: 'Videos', description: 'View your Videos'},
    {location: '/videos/channel', title: 'Channels', description: 'View the Channels of your Videos'},
    {location: '/zim', title: 'Zim', description: 'View your Zims'},
    {location: '/zim/manage', title: 'Manage Zim', description: 'Manage your Zims'},
    {
        location: '/more/calculators?calc=temperature',
        title: 'Temperature Calculator',
        description: 'Convert Celsius, Fahrenheit, Kelvin'
    },
    {
        location: '/more/calculators?calc=electrical',
        title: 'Electrical Calculator',
        description: 'Convert Volts, Ohms, Amps, Watts, Power Loss.'
    },
    {
        location: '/more/calculators?calc=antenna',
        title: 'Antenna Calculator',
        description: 'Calculate dipole length, wavelength.'
    },
    {
        location: '/more/calculators?calc=drive',
        title: 'Drive Ratio Calculator',
        description: 'Calculate pulley, gear, and sprocket ratios, RPM, torque, belt and chain length.'
    },
    {
        location: '/more/calculators?calc=water',
        title: 'Water Storage Calculator',
        description: 'Calculate water storage for your household: drinking and hygiene needs, how much to store, and how many drums, buckets, or bottles you need.'
    },
];

export const useSearch = (defaultLimit = 48, totalPages = 0, emptySearch = false, model) => {
    const navigate = useNavigate();

    const {dateRange, setDateRange, months, setDates, isEmpty: datesIsEmpty} = useSearchDate();
    const {searchParams, updateQuery, getLocationStr} = React.useContext(QueryContext);
    // `searchStr` means actually fetch the files/zims.
    const searchStr = searchParams.get('q');
    // User can search only by Tags, `searchStr` not required.
    const activeTags = searchParams.getAll('tag');
    const pages = usePages(defaultLimit, totalPages);
    // text/html, video*, image*, etc.
    const filter = searchParams.get('filter');
    // archive/video/doc/etc.
    const model_ = searchParams.get('model') || model;

    const anySearch = (!datesIsEmpty) || searchStr || (activeTags && activeTags.length > 0) || filter || model;
    const isEmpty = !anySearch;

    const setSearchStr = (value) => {
        const searchQuery = {q: value, o: 0};
        if (filter) {
            searchQuery['filter'] = filter;
        }
        const location = getLocationStr(searchQuery, '/search');
        navigate(location);
    }

    const clearSearch = () => {
        navigate({pathname: window.location.pathname, search: ''});
    }

    const setTags = (tags) => {
        updateQuery({tag: tags, anyTag: null});
    }

    const addTag = (name) => {
        const newTags = [...activeTags, name];
        setTags(newTags);
    }

    const removeTag = (name) => {
        const newTags = activeTags.filter(i => i !== name);
        setTags(newTags);
    }

    const anyTag = searchParams.get('anyTag') === 'true';
    const setAnyTag = (value) => {
        updateQuery({tag: [], anyTag: value ? 'true' : null});
    }

    return {
        activeTags, addTag, removeTag, anyTag, setAnyTag, setTags,
        filter,
        model: model_,
        pages,
        searchParams,
        searchStr,
        setSearchStr,
        clearSearch,
        months, dateRange, setDateRange, setDates,
        anySearch, isEmpty,
    }
}

export function useSuggestions(searchStr, tagNames, filter, anyTag) {
    const defaultSuggestions = {
        fileGroups: [],
        channels: [],
        domains: [],
        authors: [],
        subjects: [],
        zimsEstimates: [],
    }
    const [suggestions, setSuggestions] = React.useState(defaultSuggestions);
    const {dateRange, months} = useSearchDate();
    // channels/domains.
    const {data: generalData, sendRequest: sendGeneralReqeust, loading: generalLoading} = useLatestRequest(500);
    const {data: filesData, sendRequest: sendFilesRequest, loading: filesLoading} = useLatestRequest(500);
    // Zims are slow, so they are separate.
    const {data: zimData, sendRequest: sendZimRequest, loading: zimLoading} = useLatestRequest(500);
    const {data: otherData, sendRequest: sendOtherRequest, loading: otherLoading} = useLatestRequest(500);
    const {data: mapData, sendRequest: sendMapRequest, loading: mapLoading} = useLatestRequest(500);

    React.useEffect(() => {
        if (searchStr || (tagNames && tagNames.length > 0)) {
            const mimetypes = filterToMimetypes(filter);
            setSuggestions(defaultSuggestions);
            if (searchStr && searchStr.length > 0) {
                // We can't search Channels/Domains without some string to filter by.
                sendGeneralReqeust(async () => await searchSuggestions(searchStr));
                sendMapRequest(async () => await searchEstimateMap(searchStr));
            }
            // The files estimate always uses deep search server-side, so users know results are possible.
            sendFilesRequest(async () => await searchEstimateFiles(searchStr, tagNames, mimetypes, months, dateRange, anyTag));
            sendZimRequest(async () => await searchEstimateZims(searchStr, tagNames));
            sendOtherRequest(async () => await searchEstimateOthers(tagNames));
        }
    }, [
        searchStr,
        sendGeneralReqeust,
        sendZimRequest,
        JSON.stringify(tagNames),
        JSON.stringify(months),
        JSON.stringify(dateRange),
        filter,
        anyTag,
    ]);

    React.useEffect(() => {
        if (!_.isEmpty(generalData)) {
            setSuggestions((prevState) => {
                return {
                    ...prevState,
                    channels: generalData.channels,
                    domains: generalData.domains,
                    authors: generalData.authors,
                    subjects: generalData.subjects,
                }
            });
        }
    }, [setSuggestions, generalData]);

    React.useEffect(() => {
        if (!_.isEmpty(filesData)) {
            setSuggestions((prevState) => {
                return {...prevState, fileGroups: filesData.fileGroups, fileGroupsDeep: filesData.fileGroupsDeep}
            });
        }
    }, [setSuggestions, filesData]);

    React.useEffect(() => {
        if (!_.isEmpty(zimData)) {
            setSuggestions((prevState) => {
                return {...prevState, zimsEstimates: zimData.zimsEstimates}
            });
        }
    }, [setSuggestions, zimData]);

    React.useEffect(() => {
        if (!_.isEmpty(otherData)) {
            setSuggestions((prevState) => {
                return {...prevState, otherEstimates: otherData.others}
            });
        }
    }, [setSuggestions, otherData]);

    React.useEffect(() => {
        if (!_.isEmpty(mapData)) {
            setSuggestions((prevState) => {
                return {...prevState, mapPlaces: mapData.mapPlaces}
            });
        }
    }, [setSuggestions, mapData]);

    return {suggestions, loading: generalLoading || zimLoading || filesLoading}
}


export function useSearchSuggestions(defaultSearchStr, defaultTagNames, anyTag) {
    const navigate = useNavigate();
    const {filter} = useSearchFilter();
    const [searchStr, setSearchStr] = React.useState(defaultSearchStr || '');
    const [searchTags, setSearchTags] = React.useState(defaultTagNames);
    const {SingleTag, fuzzyMatchTagsByName} = React.useContext(TagsContext);
    const {dateRange, months, setDates, clearDate} = useSearchDate();
    const {suggestions, loading} = useSuggestions(searchStr, searchTags, filter, anyTag);
    const {deep} = useSearchDeep();
    const {getLocationStr} = React.useContext(QueryContext);

    // The results that will be displayed by <Search>.
    const [suggestionsResults, setSuggestionsResults] = useState({});
    // The results summarized.
    const [suggestionsSums, setSuggestionsSums] = useState({});

    // Disable selecting a result briefly after new suggestions arrive.
    const [selectDisabled, setSelectDisabled] = React.useState(false);
    const selectDisableTimerRef = React.useRef(null);

    const noResults = [{title: 'No results'}];

    const normalizeSuggestionsResults = (newSuggestions) => {
        // Convert the suggestions from the Backend to what SearchBox expects.
        const lowerSearchStr = searchStr ? searchStr.toLowerCase() : '';

        let results = {};

        // The dropdown always suggests the deep count so users know what is findable.  The search results
        // page shows the active mode's count, and offers deep search when it found less than promised.
        const dropdownEstimate = newSuggestions.fileGroupsDeep ?? newSuggestions.fileGroups;
        // The tab badge shows the count matching the active search mode, so it agrees with the result list.
        const fileGroupsEstimate = deep ? newSuggestions.fileGroupsDeep : newSuggestions.fileGroups;

        // Suggested results are ordered.
        if (dropdownEstimate > 0) {
            results.fileGroups = {
                name: 'Files', results: [
                    {
                        title: dropdownEstimate.toString(),
                        type: 'files',
                        // Add search query onto current location.
                        location: getLocationStr({q: searchStr}, '/search'),
                    }
                ]
            };
        } else if (dropdownEstimate === 0) {
            // Tell the user there are no files.
            results.fileGroups = {name: 'Files', results: noResults};
        }

        const zimSum = newSuggestions.zimsEstimates && newSuggestions.zimsEstimates.length > 0
            ? newSuggestions.zimsEstimates.reduce((i, j) => i + j.estimate, 0)
            : null;
        if (newSuggestions && zimSum > 0) {
            results.zimsSum = {
                name: 'Zims', results: [
                    // Navigating to Zims is not relative. We don't want to keep filters or other extra params.
                    {title: zimSum.toString(), type: 'zims', location: `/search/zim?q=${encodeURIComponent(searchStr)}`}
                ],
            };
        } else if (newSuggestions && zimSum === 0) {
            results.zimsSum = {name: 'Zims', results: noResults};
        }
        if (newSuggestions.channels && newSuggestions.channels.length > 0) {
            results.channels = {
                name: 'Channels', results: newSuggestions.channels.map(i => {
                    return {type: 'channel', title: i['name'], id: i['id'], location: `/videos/channel/${i.id}/video`}
                })
            }
        } else if (newSuggestions.channels && newSuggestions.channels.length === 0) {
            results.channels = {name: 'Channels', results: noResults};
        }
        if (newSuggestions.domains && newSuggestions.domains.length > 0) {
            results.domains = {
                name: 'Domains', results: newSuggestions.domains.map(i => {
                    return {
                        type: 'domain',
                        title: i.domain,
                        id: i.id,
                        domain: i.domain,
                        location: `/archives?domain=${i.domain}`
                    }
                })
            }
        }
        if (newSuggestions.authors && newSuggestions.authors.length > 0) {
            results.authors = {
                name: 'Authors', results: newSuggestions.authors.map(i => {
                    return {
                        type: 'author',
                        title: i.name,
                        id: i.id,
                        location: `/docs?author=${encodeURIComponent(i.name)}`
                    }
                })
            }
        }
        if (newSuggestions.subjects && newSuggestions.subjects.length > 0) {
            results.subjects = {
                name: 'Subjects', results: newSuggestions.subjects.map(i => {
                    return {
                        type: 'subject',
                        title: i.name,
                        id: i.id,
                        location: `/docs?subject=${encodeURIComponent(i.name)}`
                    }
                })
            }
        }

        // Match at most 5 Tags.
        const matchingTags = searchStr ? fuzzyMatchTagsByName(searchStr).slice(0, 5) : null;
        if (matchingTags && matchingTags.length > 0) {
            results.tags = {
                name: 'Tags', results: matchingTags.map(i => {
                    return {type: 'tag', title: i.name, location: `/search?tag=${encodeURIComponent(i.name)}`}
                })
            }
        }

        const otherSum = suggestions.otherEstimates ? _.sum(Object.values(suggestions.otherEstimates)) : 0;

        const matchingApps = SUGGESTED_APPS.filter(i =>
            i.title.toLowerCase().includes(lowerSearchStr)
            || fuzzyMatch(i.title.toLowerCase(), lowerSearchStr)
            || i.description.toLowerCase().includes(lowerSearchStr)
            || fuzzyMatch(i.description.toLowerCase(), lowerSearchStr));
        if (matchingApps && matchingApps.length > 0) {
            // Match at most 5 apps.
            results.apps = {name: 'Apps', results: matchingApps.slice(0, 5)};
        }

        // Detect coordinates (e.g., "40.76, -111.89" or "40.76 -111.89").
        const coordMatch = searchStr && searchStr.trim().match(
            /^(-?\d+\.?\d*)[,\s]+(-?\d+\.?\d*)$/
        );
        // Map places suggestion in dropdown.
        if (newSuggestions.mapPlaces > 0) {
            results['map places'] = {
                name: 'Map Places', results: [{
                    type: 'search',
                    title: `Map: ${newSuggestions.mapPlaces} places`,
                    description: 'Search map locations',
                    location: `/search/map?q=${encodeURIComponent(searchStr)}`,
                }]
            };
        }

        if (coordMatch) {
            const lat = parseFloat(coordMatch[1]);
            const lon = parseFloat(coordMatch[2]);
            if (lat >= -90 && lat <= 90 && lon >= -180 && lon <= 180) {
                // Derive zoom from decimal precision: 0dp=3, 1dp=7, 2dp=10, 3dp=13, 4dp=16, 5+=18
                const maxDecimals = Math.max(
                    (coordMatch[1].split('.')[1] || '').length,
                    (coordMatch[2].split('.')[1] || '').length,
                );
                const zoom = Math.min([3, 7, 10, 13, 16, 18][maxDecimals] || 18, 18);
                results.map = {
                    name: 'Map', results: [{
                        type: 'map',
                        title: `${lat}, ${lon}`,
                        description: 'View on map',
                        location: `/map?lat=${lat}&lon=${lon}&z=${zoom}`,
                    }]
                };
            }
        }

        setSuggestionsResults(results);
        setSuggestionsSums({
            fileGroups: fileGroupsEstimate,
            fileGroupsDeep: newSuggestions.fileGroupsDeep,
            zims: zimSum,
            otherSum: otherSum,
            mapPlaces: newSuggestions.mapPlaces || 0,
            channels: newSuggestions.channels.length,
            domains: newSuggestions.domains.length,
            authors: newSuggestions.authors?.length,
            subjects: newSuggestions.subjects?.length,
            tags: matchingTags?.length,
            apps: matchingApps?.length,
        });
    }

    const suggestionSelectDelay = 250;

    React.useEffect(() => {
        setSuggestionsSums({});
        setSuggestionsResults({});

        if (!_.isEmpty(suggestions)) {
            // Start a brief window where selecting results is disabled to prevent accidental clicks
            // when the dropdown re-renders with new suggestions.
            if (selectDisableTimerRef.current) {
                clearTimeout(selectDisableTimerRef.current);
            }
            setSelectDisabled(true);
            selectDisableTimerRef.current = setTimeout(() => setSelectDisabled(false), suggestionSelectDelay);

            normalizeSuggestionsResults(suggestions);
        }
    }, [JSON.stringify(suggestions), deep]);

    // Clear timer on unmount.
    React.useEffect(() => {
        return () => {
            if (selectDisableTimerRef.current) {
                clearTimeout(selectDisableTimerRef.current);
            }
        };
    }, []);

    // User clicked on a result in the dropdown.
    const handleResultSelect = ({result}) => {
        if (selectDisabled) {
            console.debug('Selection temporarily disabled after suggestions update');
            return;
        }
        if (result.location) {
            console.info(`useSearchSuggestions Navigating: ${result.location}`)
            navigate(result.location);
        } else {
            console.error('No location to navigate');
        }
    }

    const resultRenderer = ({type, title, description}) => {
        if (type === 'tag') {
            return <SingleTag name={title}/>;
        }

        if (description) {
            return <>
                <Header as='h4'>{title}</Header>
                {description}
            </>
        }
        // No specific renderer, use the generic.
        return <span>{title}</span>
    };

    return {
        suggestions,
        suggestionsResults,
        suggestionsSums,
        searchStr, setSearchStr,
        setSearchTags,
        months, dateRange, setDates, clearDate,
        handleResultSelect,
        resultRenderer,
        loading,
    }
}


export function SearchView({suggestions, suggestionsSums, loading}) {
    const location = useLocation();
    const search = location.search;

    const filesTabName = <span>Files <Label>{normalizeEstimate(suggestionsSums?.fileGroups)}</Label></span>;
    const zimsTabName = <span>Zims <Label>{normalizeEstimate(suggestionsSums?.zims)}</Label></span>;
    const mapTabName = <span>Map <Label>{normalizeEstimate(suggestionsSums?.mapPlaces)}</Label></span>;
    const othersTabName = <span>Other <Label>{normalizeEstimate(suggestionsSums?.otherSum)}</Label></span>;

    const links = [
        {text: filesTabName, to: `/search${search}`, key: 'filesSearch_', end: true},
        {text: zimsTabName, to: `/search/zim${search}`, key: 'zimsSearch'},
        {text: mapTabName, to: `/search/map${search}`, key: 'mapSearch'},
        {text: othersTabName, to: `/search/other${search}`, key: 'othersSearch'},
    ];

    // The view toggle only applies to the Files tab; show it in the tab row's right slot there.
    const isFilesTab = !/\/(zim|map|other)$/.test(location.pathname);

    return <React.Fragment>
        <TabLinks links={links} right={isFilesTab ? <SearchViewButton headlines/> : null}/>
        <Routes>
            <Route path='/*' element={<FilesSearchView showView={false}
                                                       deepEstimate={suggestionsSums?.fileGroupsDeep}/>}/>
            <Route path='/zim' exact element={<ZimSearchView suggestions={suggestions} loading={loading}/>}/>
            <Route path='/map' exact element={<MapSearchView/>}/>
            <Route path='/other' exact element={<OtherSearchView loading={loading}/>}/>
        </Routes>
    </React.Fragment>
}

export function SearchIconButton() {
    /*
     * A single button which opens the search modal via keyboard shortcuts context.
     *
     * `wrolpi-navbar-link`, not the leftover `item` class, which carries no rules at all
     * now that the stylesheet defining it is gone: no pointer cursor, no hover highlight, and a hit area of
     * whatever the 18px glyph occupied rather than the height of the bar.  It is the same
     * kind of thing as Help and Admin and now has the same affordance.
     */
    const {openSearchModal} = React.useContext(KeyboardShortcutsContext);

    return (
        <a className='wrolpi-navbar-link' onClick={openSearchModal}
           role='button' tabIndex={0} aria-label='Search'
           onKeyDown={e => (e.key === 'Enter' || e.key === ' ') && openSearchModal()}>
            <Icon name='search'/>
            <ShortcutHint shortcutKey="K"/>
        </a>
    );
}

function SearchChannelPreview({channel}) {
    return <div>
        <Link to={`/videos/channel/${channel.id}/video`}>
            {channel.name}
        </Link>
    </div>
}

function OtherSearchView({loading}) {
    const {searchParams} = React.useContext(QueryContext);
    const [activeValue, setActiveValue] = React.useState('channels');
    const activeTags = searchParams.getAll('tag');
    const {channels, loading: channelsLoading} = useSearchChannels(activeTags);

    if (loading || channelsLoading) {
        return <Panel><Loading/></Panel>
    }

    return <Accordion value={activeValue} onChange={setActiveValue}>
        <Accordion.Item value='channels'>
            <Accordion.Control>
                <span style={{display: 'inline-flex', alignItems: 'center', gap: 8}}>
                    <Header as='h3' style={{margin: 0}}>Channels</Header>
                    <Label>{normalizeEstimate(channels.length)}</Label>
                </span>
            </Accordion.Control>
            <Accordion.Panel>
                <Stack gap='xs'>
                    {!_.isEmpty(channels) ?
                        channels.map(i => <SearchChannelPreview key={i.id} channel={i}/>)
                        : 'No Channels'}
                </Stack>
            </Accordion.Panel>
        </Accordion.Item>
    </Accordion>
}