import React from "react";
import {Link, NavLink} from "react-router";
import {Dropdown, Icon as SIcon, Menu} from "semantic-ui-react";
import {Media, SettingsContext, StatusContext, ThemeContext} from "../contexts/contexts";
import {DarkModeToggle, HotspotStatusIcon, useLocalStorage} from "./Common";
import {ShareButton} from "./Share";
import {
    useCPUTemperature,
    useDriveHealth,
    useDriveTemperature,
    useIOStats,
    useLoad,
    useMemoryStats,
    usePowerStats,
    useWROLMode
} from "../hooks/customHooks";
import {useReorganizationStatus} from "../contexts/FileWorkerStatusContext";
import {SearchIconButton} from "./Search";
import {Icon, Popup} from "./Theme";
import {HELP_VIEWER_URI, NAME, semanticUIColorMap} from "./Vars";
import {useOverflowNav} from "../hooks/useOverflowNav";
import _ from "lodash";

function updateFavicon(colorName) {
    // Fall back to violet if invalid color
    const safeColor = colorName in semanticUIColorMap ? colorName : 'violet';
    const faviconPath = `/favicon-${safeColor}.svg`;

    // Update all favicon links
    const iconLinks = document.querySelectorAll('link[rel="icon"], link[rel="shortcut icon"]');
    iconLinks.forEach(link => {
        link.href = faviconPath;
    });

    // Also update the 32x32 and 16x16 specific icons if they exist
    const icon32 = document.querySelector('link[sizes="32x32"]');
    const icon16 = document.querySelector('link[sizes="16x16"]');
    if (icon32) icon32.href = faviconPath;
    if (icon16) icon16.href = faviconPath;

    // Update theme-color meta tag for iOS/Android status bar
    const hexColor = semanticUIColorMap[safeColor];
    const themeColorMeta = document.querySelector('meta[name="theme-color"]');
    if (themeColorMeta) themeColorMeta.content = hexColor;
}

const help = {to: HELP_VIEWER_URI, text: 'Help', key: 'help', target: '_blank'};
const admin = {to: '/admin', text: 'Admin', key: 'admin'};
const rightLinks = [help, admin];
const allLinks = [
    {text: 'Videos', to: '/videos', key: 'videos'},
    {text: 'Archive', to: '/archives', key: 'archive'},
    {text: 'Docs', to: '/docs', key: 'docs'},
    {text: 'Map', to: '/map', key: 'map'},
    {text: 'Files', to: '/files', key: 'files'},
    {text: 'Playlists', to: '/playlists', key: 'playlists'},
    {text: 'Zim', to: '/zim', key: 'zim'},
    {text: 'Inventory', to: '/inventory', key: 'inventory'},
    {to: '/more/calculators', text: 'Calculators', key: 'calculators', end: true},
    {text: 'Flasher', to: '/flasher', key: 'flasher'},
    {to: '/more/statistics', text: 'Statistics', key: 'statistics', end: true},
];

function DropdownLinks({link}) {
    return <Dropdown item text={link.text} direction='left'>
        <Dropdown.Menu>
            {link.links.map(l => <MenuLink key={l.to} link={l}/>)}
        </Dropdown.Menu>
    </Dropdown>
}

function MenuLink({link}) {
    // Wrapper around NavLink to handle Navlink/Dropdown change.
    if (link.links) {
        return <DropdownLinks link={link}/>
    } else {
        const end = link.end ? {end: true} : {end: undefined};
        const target = link.target ? {target: link.target} : {};
        return <NavLink
            className='item'
            to={link.to}
            {...end}
            {...target}
        >
            {link.text}
        </NavLink>
    }
}

function NavIconWrapper({children}) {
    if (children) {
        return <div style={{marginTop: '0.8em', marginLeft: '1.5em'}}>{children}</div>
    } else {
        // Do not use navbar space if children is empty.
        return <React.Fragment/>
    }
}

function useNavColorSetting() {
    // Use localstorage to avoid flickering navbar color on startup.
    const {settings} = React.useContext(SettingsContext);
    const [navColor, setNavColor] = useLocalStorage('nav_color', 'violet');

    React.useEffect(() => {
        if (!_.isEmpty(settings)) {
            setNavColor(settings.nav_color);
        }
    }, [settings.nav_color]);

    // Update favicon to match nav color
    React.useEffect(() => {
        if (navColor) {
            updateFavicon(navColor);
        }
    }, [navColor]);

    return navColor
}

export function NavBar() {
    const wrolModeEnabled = useWROLMode();
    const {status} = React.useContext(StatusContext);
    const navColor = useNavColorSetting();
    const wrolpiIcon = <img src='/icon.svg' height='32px' width='32px' alt='WROLPi Home Icon'/>;
    const name = <i>{NAME || wrolpiIcon}</i>;
    const topNavText = wrolModeEnabled ? <>{name}&nbsp; <SIcon name='lock'/></> : name;
    const {i} = React.useContext(ThemeContext);

    const homeLink = <NavLink className='item' to='/' style={{paddingTop: 0, paddingBottom: 0}}>
        {topNavText}
    </NavLink>;

    // Red/Yellow colors will blend in to some navbar colors, swap the colors for high contrast.
    const conflictingColors = ['red', 'orange', 'yellow', 'olive', 'pink'];
    const [lowWarningColor, highWarningColor] = conflictingColors.includes(navColor)
        ? [null, 'black']
        : ['yellow', 'red'];

    // Generic system load, the least important warning.
    const {minute_1, mediumLoad, highLoad} = useLoad();
    let systemLoadIcon;
    if (mediumLoad || highLoad) {
        // System load is high, display a warning icon.
        const color = highLoad ? highWarningColor : lowWarningColor;
        const icon = <Link to='/admin/status'>
            <Icon name='tachometer alternate' size='large' color={color}/>
        </Link>;
        systemLoadIcon = <Popup content={`Load: ${minute_1}`} trigger={icon}/>
    }

    // RAM consumption.
    const {percent: memoryPercent} = useMemoryStats();
    let memoryIcon;
    if (memoryPercent > 80) {
        const color = memoryPercent > 90 ? highWarningColor : lowWarningColor;
        const icon = <Link to='/admin/status' color={color}>
            <Icon name='microchip' size='large'/>
        </Link>;
        memoryIcon = <Popup content={`System Memory: ${memoryPercent.toFixed()}%`} trigger={icon}/>
    }

    // Any disk is busy and processes are waiting.
    const {percentIOWait} = useIOStats();
    let diskWaitIcon;
    if (percentIOWait >= 50) {
        // Processes are waiting on disk, display a warning icon.
        const color = percentIOWait > 75 ? highWarningColor : lowWarningColor;
        const icon = <Link to='/admin/status'>
            <Icon name='disk' size='large' color={color}/>
        </Link>;
        diskWaitIcon = <Popup content={`Processes waiting on disk: ${percentIOWait.toFixed()}%`} trigger={icon}/>
    }

    // CPU temperature.
    const {temperature, highTemperature, criticalTemperature} = useCPUTemperature();
    let temperatureIcon;
    if (temperature && temperature >= highTemperature) {
        // CPU temperature is high, display a warning icon.
        const color = temperature >= criticalTemperature ? highWarningColor : lowWarningColor;
        const name = temperature >= criticalTemperature ? 'thermometer' : 'thermometer half';
        const icon = <Icon data-testid='cpuTemperatureIcon' name={name} size='large' color={color}/>
        const link = <Link to='/admin/status'>{icon}</Link>;
        temperatureIcon = <Popup content={`CPU: ${temperature.toFixed()}°C`} trigger={link}/>;
    }

    // Hard-drive temperature.  An overheating drive risks data loss.
    const {
        device: hotDrive,
        temperature: driveTemperature,
        highTemperature: driveHighTemperature,
        criticalTemperature: driveCriticalTemperature,
    } = useDriveTemperature();
    let driveTemperatureIcon;
    if (driveTemperature && driveTemperature >= driveHighTemperature) {
        const color = driveTemperature >= driveCriticalTemperature ? highWarningColor : lowWarningColor;
        const icon = <Icon data-testid='driveTemperatureIcon' name='hdd' size='large' color={color}/>
        const link = <Link to='/admin/controller'>{icon}</Link>;
        driveTemperatureIcon = <Popup content={`${hotDrive}: ${driveTemperature.toFixed()}°C`} trigger={link}/>;
    }

    // A drive's SMART health is degraded.  FAIL is an imminent failure (back
    // up now); WARN means unreadable/pending sectors are accumulating.  Always
    // displayed (like power); too important to hide behind a transient warning
    // in the priority chain.  Links to the Controller page, which shows the
    // SMART detail (the Status page does not).
    const {failingDevices, failing: driveFailing, warningDevices, warning: driveWarning} = useDriveHealth();
    let driveHealthIcon;
    if (driveFailing) {
        const icon = <Icon data-testid='driveHealthIcon' name='warning sign' size='large' color={highWarningColor}/>;
        const link = <Link to='/admin/controller'>{icon}</Link>;
        const message = failingDevices.length === 1
            ? `Drive ${failingDevices[0]} is failing its SMART health check! Back up your data.`
            : `Drives failing SMART health check: ${failingDevices.join(', ')}. Back up your data.`;
        driveHealthIcon = <Popup content={message} trigger={link}/>;
    } else if (driveWarning) {
        const icon = <Icon data-testid='driveHealthIcon' name='warning sign' size='large' color={lowWarningColor}/>;
        const link = <Link to='/admin/controller'>{icon}</Link>;
        const message = warningDevices.length === 1
            ? `Drive ${warningDevices[0]} has unreadable or pending sectors — check its SMART health.`
            : `Drives with unreadable or pending sectors: ${warningDevices.join(', ')}. Check their SMART health.`;
        driveHealthIcon = <Popup content={message} trigger={link}/>;
    }

    // Power issues, this is always displayed if detected.
    const {underVoltage, overCurrent} = usePowerStats();
    let powerIcon;
    if (underVoltage || overCurrent) {
        const name = underVoltage ? 'power cord' : 'lightning';
        const icon = <Icon name={name} size='large' color={highWarningColor}/>;
        const message = underVoltage
            ? 'Under-voltage detected! Your power supply is insufficient!'
            : 'Over-current detected! Your peripherals are using too much power!';
        powerIcon = <Popup content={message} trigger={icon}/>;
    }

    // Display the temperature icon first because it can cause the system to throttle.  The rest are in order of effects
    // that will slow down the system and the user should address.  Generic load is last because it is probably not an
    // issue.
    const warningIcon = temperatureIcon || driveTemperatureIcon || diskWaitIcon || memoryIcon || systemLoadIcon;

    const {isReorganizing, taskType, collectionId, collectionKind} = useReorganizationStatus();

    let processingLink;
    if (status && status.flags) {
        if (status.flags.file_worker_busy) {
            // Smart navigation based on what the file worker is doing
            if (isReorganizing && collectionId && collectionKind) {
                // Single collection reorganization - navigate to that collection
                if (collectionKind === 'channel') {
                    processingLink = `/videos/channel/${collectionId}/edit`;
                } else if (collectionKind === 'domain') {
                    processingLink = `/archives/domain/${collectionId}/edit`;
                } else {
                    processingLink = '/files';
                }
            } else if (isReorganizing && taskType === 'batch_reorganize' && collectionKind) {
                // Batch reorganization - navigate to settings page for that kind
                if (collectionKind === 'channel') {
                    processingLink = '/videos/settings';
                } else if (collectionKind === 'domain') {
                    processingLink = '/archives/settings';
                } else {
                    processingLink = '/files';
                }
            } else {
                processingLink = '/files';
            }
        }
    }
    const processingIcon = processingLink &&
        <Link to={processingLink}>
            <Icon loading name='circle notch' size='large'/>
        </Link>;

    let apiDownIcon;
    if (window.apiDown) {
        apiDownIcon = <Popup
            content='API is not responding'
            trigger={<Icon name='plug' color={highWarningColor}/>}
        />
    }

    // Upgrade available notification - only show on native (non-Docker) installs and when WROL Mode is disabled
    let upgradeIcon;
    if (status?.update_available && !status?.dockerized && !wrolModeEnabled) {
        const commitsBehind = status.commits_behind || 0;
        const branch = status.git_branch || 'unknown';
        const icon = <Link to='/admin/settings#upgrade'>
            <Icon name='arrow alternate circle up' size='large' color='green'/>
        </Link>;
        upgradeIcon = <Popup
            content={`Upgrade available: ${commitsBehind} commit(s) behind on ${branch}`}
            trigger={icon}
        />;
    }

    const icons = <React.Fragment>
        <NavIconWrapper>{apiDownIcon}</NavIconWrapper>
        <NavIconWrapper>{processingIcon}</NavIconWrapper>
        <NavIconWrapper>{upgradeIcon}</NavIconWrapper>
        <NavIconWrapper>{driveHealthIcon}</NavIconWrapper>
        <NavIconWrapper>{powerIcon}</NavIconWrapper>
        <NavIconWrapper>{warningIcon}</NavIconWrapper>
        <NavIconWrapper><ShareButton/></NavIconWrapper>
        <NavIconWrapper><HotspotStatusIcon/></NavIconWrapper>
        <NavIconWrapper><DarkModeToggle/></NavIconWrapper>
    </React.Fragment>;

    return <>
        <Media between={['mobile', 'tablet']}>
            <Menu {...i} attached='top' color={navColor} id='global_navbar'>
                {homeLink}
                <Menu.Menu position='right'>
                    {icons}
                    <SearchIconButton/>
                    <Dropdown item icon="bars">
                        <Dropdown.Menu>
                            {allLinks.map(i => <MenuLink link={i} key={i.key}/>)}
                            {rightLinks.map(i => <MenuLink link={i} key={i.key}/>)}
                        </Dropdown.Menu>
                    </Dropdown>
                </Menu.Menu>
            </Menu>
        </Media>
        <Media greaterThanOrEqual='tablet'>
            <DesktopNav i={i} navColor={navColor} homeLink={homeLink} icons={icons}/>
        </Media>
    </>
}

function DesktopNav({i, navColor, homeLink, icons}) {
    const containerRef = React.useRef(null);
    const homeRef = React.useRef(null);
    const rightMenuRef = React.useRef(null);
    const moreRef = React.useRef(null);
    const {visibleLinks, overflowLinks, itemRefCallback, isReady} = useOverflowNav({
        links: allLinks,
        containerRef,
        homeRef,
        rightMenuRef,
        moreRef,
    });

    return (
        <div ref={containerRef}>
            <Menu {...i} attached='top' color={navColor} id='global_navbar'>
                <span ref={homeRef} style={{display: 'contents'}}>{homeLink}</span>
                {(isReady ? visibleLinks : allLinks).map((link, idx) => (
                    <span
                        key={link.key}
                        ref={itemRefCallback(idx)}
                        style={isReady ? {display: 'contents'} : {visibility: 'hidden', flexShrink: 0}}
                    >
                        <MenuLink link={link}/>
                    </span>
                ))}
                {!isReady && <span ref={moreRef} style={{visibility: 'hidden', flexShrink: 0}}>
                    <Dropdown item text='More'><Dropdown.Menu/></Dropdown>
                </span>}
                {isReady && overflowLinks.length > 0 &&
                    <DropdownLinks link={{text: 'More', key: 'more', links: overflowLinks}}/>}
                <div ref={rightMenuRef} className='right menu'>
                    {icons}
                    <SearchIconButton/>
                    {rightLinks.map(i => <MenuLink link={i} key={i.key}/>)}
                </div>
            </Menu>
        </div>
    );
}