/**
 * @type {string | null}
 */
var fromStation = null
/**
 * @type {string | null}
 */
var toStation = null
/**
 * @type {Date | null}
 */
var departureDate = null
var arrivalInsteadOfDeparture = false
var transitKind = {
    ice: true,
    ic: true,
    re: true,
    rb: true,
    s: true,
    bus: true,
    ferry: true,
    u: true,
    tram: true,
}
var starred = []

/**
 * @type {{id: string, name: string}[]}
 */
var knownStations = []

/**
 * @type {'unavailable' | 'notRequested' | 'waiting' | 'gotData'}
 */
var nearbyStatus = 'notRequested'
var nearbyStations = []

function goToStation(stationId) {
    var url = new URL(window.location.href)
    if (!fromStation) {
        url.searchParams.set('from', stationId)
    }
    else if (!toStation) {
        url.searchParams.set('to', stationId)
    }
    // url.searchParams.set('date', new Date().toISOString())
    window.location.href = url.toString()
}

function setDepartureDate(departureDate) {
    var url = new URL(window.location.href)
    url.searchParams.set('departureDate', departureDate.toISOString())
    window.location.href = url.toString()
}

function searchNormalize(str) {
    return str
        .toLowerCase()
        .replaceAll('ă', 'a')
        .replaceAll('â', 'a')
        .replaceAll('î', 'i')
        .replaceAll('ș', 's')
        .replaceAll('ț', 't')
}

var focusedElement = null

var _rebuildDebounce = null
var _rebuildRequested = false
function createSuggestion(suggestion, index) {
    delete suggestion['products']
    var suggestionDiv = document.createElement('div')
    suggestionDiv.classList.add('suggestion')

    var suggestionLi = document.createElement('li')
    suggestionDiv.appendChild(suggestionLi)

    suggestionLi.classList.add('items')
    if (index) {
        suggestionLi.tabIndex = index + 1
    }
    suggestionLi.style.padding = '2px 0'

    function onAction(e) {
        goToStation(JSON.stringify(suggestion))
    }
    suggestionLi.addEventListener('click', onAction)
    suggestionLi.addEventListener('keypress', function (e) {
        if (e.key == 'Enter') {
            onAction(e)
        }
    })
    suggestionLi.addEventListener('focus', function (e) {
        focusedElement = suggestionLi
    })

    var stationNameP = document.createElement('p')
    suggestionLi.appendChild(stationNameP)

    var stationNameSpan = document.createElement('span')
    stationNameP.append(stationNameSpan)
    stationNameSpan.textContent = suggestion.name || suggestion.address
    stationNameSpan.classList.add('pri', 'stationName')

    if (suggestion.distance) {
        stationNameP.append(' ')
        var stationDistanceSpan = document.createElement('span')
        stationNameP.append(stationDistanceSpan)
        stationDistanceSpan.append('(', suggestion.distance.toString(), ' m)')
        stationDistanceSpan.classList.add('stationDistance')
    }


    if (window.localStorage) {
        var suggestionDistance = suggestion['distance']
        delete suggestion['distance']
        var suggestionLink = document.createElement('a')
        suggestionLink.classList.add('no-custom-a')

        var suggestionStar = document.createElement('object')
        suggestionLink.appendChild(suggestionStar)
        suggestionStar.classList.add('star')
        suggestionStar.type = 'image/svg+xml'
        function setStar() {
            if (starred.includes(JSON.stringify(suggestion))) {
                suggestionStar.data = '/icons/star_full.svg'
                suggestionStar.classList.add('checked')
            }
            else {
                suggestionStar.data = '/icons/star_empty.svg'
                suggestionStar.classList.remove('checked')
            }
        }
        suggestionLink.addEventListener('click', function (event) {
            event.preventDefault()
            if (starred.includes(JSON.stringify(suggestion))) {
                starred = starred.filter(function (s) {
                    return s !== suggestion
                })
            } else {
                starred.push(JSON.stringify(suggestion))
            }
            setStar()
            localStorage.setItem('stations/starred', JSON.stringify(starred))
        })
        setStar()
        suggestionDiv.appendChild(suggestionLink)
        suggestion['distance'] = suggestionDistance
    }

    // var trainCompanyP = document.createElement('p')
    // suggestionLi.appendChild(trainCompanyP)

    // trainCompanyP.textContent = suggestion.company
    // trainCompanyP.classList.add('thi')
    return suggestionDiv
}
function rebuildSuggestions() {
    if (_rebuildDebounce !== null) {
        _rebuildRequested = true
        return
    }

    _rebuildRequested = false
    _rebuildDebounce = 123

    var suggestionsArea = document.getElementById('suggestionsArea')
    while (suggestionsArea.childNodes.length > 0) {
        suggestionsArea.childNodes[0].remove()
    }

    var suggestions = knownStations.slice()
    if (suggestions.length === 0) {
        suggestions = starred.map(function (s) { return JSON.parse(s) })
    }

    suggestions.forEach(function (suggestion, index) {
        suggestionsArea.appendChild(createSuggestion(suggestion, index))
    })

    if (nearbyStatus !== 'unavailable') {
        suggestionsArea.appendChild(h4('Nearby stations'))
        if (nearbyStatus === 'notRequested') {
            suggestionsArea.appendChild(a('', 'Load nearby stations').event$('click', function (event) {
                event.preventDefault()
                var latitude = 0
                var longitude = 0
                var watchId = navigator.geolocation.watchPosition(
                    function (data) {
                        if (data.coords.latitude !== latitude || data.coords.longitude !== longitude) {
                            latitude = data.coords.latitude
                            longitude = data.coords.longitude
                            var geoUrl = new URL('https://v6.db.transport.rest/locations/nearby')
                            geoUrl.searchParams.append('latitude', data.coords.latitude.toString())
                            geoUrl.searchParams.append('longitude', data.coords.longitude.toString())
                            geoUrl.searchParams.append('results', '10')
                            fetch(geoUrl)
                                .then(function (response) {
                                    return response.json()
                                })
                                .then(function (data) {
                                    nearbyStatus = 'gotData'
                                    nearbyStations = data
                                    rebuildSuggestions()
                                })
                                .catch(function () {
                                    nearbyStatus = 'unavailable'
                                    rebuildSuggestions()
                                })
                        }
                    },
                    function (error) {
                        if (nearbyStations.length === 0) {
                            nearbyStatus = 'unavailable'
                            rebuildSuggestions()
                        }
                        navigator.geolocation.clearWatch(watchId)
                    },
                    {
                        enableHighAccuracy: true,
                    },
                )
                nearbyStatus = 'waiting'
                rebuildSuggestions()
            }))
        }
        else if (nearbyStatus === 'waiting') {
            var waitingP = document.createElement('p')
            suggestionsArea.append(waitingP)
            waitingP.append('Loading...')
            waitingP.classList.add('pri')
        }
        else if (nearbyStatus === 'gotData') {
            nearbyStations.forEach(function (suggestion, index) {
                suggestionsArea.appendChild(createSuggestion(suggestion, suggestions.length + index))
            })
        }
    }

    setTimeout(function () {
        _rebuildDebounce = null
        if (_rebuildRequested) {
            rebuildSuggestions()
        }
    }, 500)
}

var fetchAbortController = new AbortController()
function reloadSuggestions() {
	var stationNameInput = document.getElementById('stationName')
	var stationName = searchNormalize(stationNameInput.value.trim())

	var locationsUrl = new URL('https://v6.db.transport.rest/locations')
	locationsUrl.searchParams.set('query', stationName)
	locationsUrl.searchParams.set('limit', '25')
	locationsUrl.searchParams.set('fuzzy', 'true')
	locationsUrl.searchParams.set('stops', 'true')
	locationsUrl.searchParams.set('addresses', 'true')
	locationsUrl.searchParams.set('poi', 'true')

	fetchAbortController.abort()
	fetchAbortController = new AbortController()
	fetch(locationsUrl.toString(), { signal: fetchAbortController.signal })
		.then(function (response) {
            if (response.ok) {
                return response.json()
            }
            else {
                return {}
            }
		})
		.then(function (data) {
			if (data) {
				knownStations = Object.values(data)
				rebuildSuggestions()
			}
		})
}

function lsk() {
    document.getElementById('stationName').focus()
}

function csk() {
    if (focusedElement == null) {
        return
    }

    focusedElement.click()
}

window.addEventListener('load', function (e) {
    if ('geolocation' in navigator) {}
    else {
        nearbyStatus = 'unavailable'
    }

    var sp = new URL(window.location.href).searchParams
    fromStation = sp.get('from')
    var fromJson = JSON.parse(fromStation || 'null')
    toStation = sp.get('to')
    var toJson = JSON.parse(toStation || 'null')
    var departureDateStr = sp.get('departureDate')
    if (departureDateStr) {
        departureDate = new Date(departureDateStr)
    }

    var titleH1 = document.querySelector("header > h1")
    if (!fromStation) {
        titleH1.textContent = 'Find Route - From'
    }
    else if (!toStation) {
        titleH1.textContent = 'Find Route - To'
    }
    else if (!departureDate) {
        titleH1.textContent = 'Find Route - Date'
    }
    else {
        // titleH1.textContent = `${fromJson.name || fromJson.address} - ${toJson.name || toJson.address}`
        titleH1.textContent = 'Find Route - Configure'
    }

    if (window.localStorage) {
        var maybeTransitKind = JSON.parse(localStorage.getItem('config-route/transitKind'))
        if (maybeTransitKind) {
            transitKind = maybeTransitKind
        }

        var maybeStarred = JSON.parse(localStorage.getItem('stations/starred'))
        if (maybeStarred) {
            starred = maybeStarred
        }
    }

    var footer = document.querySelector('footer')

    if (!fromStation || !toStation) {
        // Build station selection UI
        document.body.insertBefore(
            h4(
                label('Station Name').att$('for', 'stationName'),
            ),
            footer,
        )
        // var stationNameH4 = document.createElement('h4')
        // document.body.insertBefore(stationNameH4, footer)
        // var stationNameLabel = document.createElement('label')
        // stationNameH4.appendChild(stationNameLabel)
        // stationNameLabel.htmlFor = 'stationName'
        // stationNameLabel.textContent = 'Station Name'

        document.body.insertBefore(
            input('search').id$('stationName').att$('name', 'stationName').class$('items'),
            footer,
        )
        // var stationNameInput = document.createElement('input')
        // document.body.insertBefore(stationNameInput, footer)
        // stationNameInput.type = 'search'
        // stationNameInput.classList.add('items')
        // stationNameInput.name = 'stationName'
        // stationNameInput.id = 'stationName'

        document.body.insertBefore(h4('Suggestions'), footer)
        // var suggestionsH4 = document.createElement('h4')
        // document.body.insertBefore(suggestionsH4, footer)
        // suggestionsH4.textContent = 'Suggestions'

        var contentDiv = document.createElement('div')
        document.body.insertBefore(contentDiv, footer)
        contentDiv.classList.add('content')
        var suggestionsUl = document.createElement('ul')
        contentDiv.appendChild(suggestionsUl)
        suggestionsUl.id = 'suggestionsArea'
        rebuildSuggestions()

        document.querySelector('.csk').textContent = 'Search'

        var stationName = document.getElementById('stationName')
        stationName.addEventListener('input', function (e) {
            reloadSuggestions()
        })
        stationName.addEventListener('focus', function (e) {
            focusedElement = stationName
            document.getElementsByClassName('lsk')[0].textContent = ''
            document.getElementsByClassName('csk')[0].textContent = 'Search'
        })
        stationName.addEventListener('blur', function (e) {
            document.getElementsByClassName('lsk')[0].textContent = 'Search'
            document.getElementsByClassName('csk')[0].textContent = 'Select'
        })
        stationName.addEventListener('keypress', function (e) {
            if (e.key == 'Enter') {
                goToStation(stationName.value.trim())
            }
        })
    }
    else if (!departureDate) {
        var departureDateH4 = document.createElement('h4')
        document.body.insertBefore(departureDateH4, footer)
        departureDateH4.textContent = 'Departure Date'

        var contentDiv = document.createElement('div')
        document.body.insertBefore(contentDiv, footer)
        contentDiv.classList.add('content')
        var departureDateUl = document.createElement('ul')
        contentDiv.appendChild(departureDateUl)
        departureDateUl.id = 'suggestionsArea'

        for (var i = -1, departureOption = (function () { var d = new Date(); d.setDate(d.getDate() - 1); return d })(); i < 30; i++, departureOption.setDate(departureOption.getDate() + 1)) {
            var suggestionLi = document.createElement('li')
            departureDateUl.appendChild(suggestionLi)
            suggestionLi.classList.add('items')
            suggestionLi.tabIndex = i + 10
            // Capture
            ;(function () {
                var d = new Date(departureOption.getTime())
                function onAction() {
                    setDepartureDate(d)
                }
                suggestionLi.addEventListener('click', onAction)
                suggestionLi.addEventListener('keypress', function (e) {
                    if (e.key == 'Enter') {
                        onAction(e)
                    }
                })
                suggestionLi.addEventListener('focus', function (e) {
                    focusedElement = suggestionLi
                })
                if (i === 0) {
                    suggestionLi.focus()
                }
            })()
            var innerP = document.createElement('p')
            suggestionLi.appendChild(innerP)
            innerP.classList.add('pri')
            var innerPre = document.createElement('pre')
            innerP.appendChild(innerPre)
            innerPre.textContent = `${departureOption.getDate().toString().padStart(2, '0')}.${(departureOption.getMonth() + 1).toString().padStart(2, '0')}.${departureOption.getFullYear().toString().padStart(4, '0')}`
            if (i === 0) {
                innerPre.textContent += ' (today)'
            }
        }

        document.querySelector('.csk').textContent = 'Select'
    }
    else {
        // var contentDiv = document.createElement('div')
        // document.body.insertBefore(contentDiv, footer)
        // contentDiv.classList.add('content')
        // contentDiv.style.display = 'flex'
        // contentDiv.style.flexDirection = 'column'

        function updateSearchLink() {
            var a = document.getElementById('search-link')
            var url = new URL(window.location.href)
            url.pathname = 'route.html'
            if (arrivalInsteadOfDeparture) {
                url.searchParams.delete('departureDate')
                url.searchParams.set('arrivalDate', departureDate.toISOString())
            }
            else {
                url.searchParams.delete('arrivalDate')
                url.searchParams.set('departureDate', departureDate.toISOString())
            }
            url.searchParams.set('from', JSON.stringify(fromJson))
            url.searchParams.set('to', JSON.stringify(toJson))
            url.searchParams.set('transitKind', JSON.stringify(transitKind))
            a.href = url.toString()
        }

        function transitKindCheckChanged(event) {
            transitKind[event.target.id.slice(13)] = event.target.checked
            if (window.localStorage) {
                localStorage.setItem('config-route/transitKind', JSON.stringify(transitKind))
            }
            updateSearchLink()
        }

        function timeKindRadioChanged(event) {
            var kind = event.target.id.split('-')[2]
            if (kind === 'arrival') {
                arrivalInsteadOfDeparture = true
            }
            else if (kind === 'departure') {
                arrivalInsteadOfDeparture = false
            }
            updateSearchLink()
        }

        var contentDiv = div(
            h4('Route'),
            p('From').class$('thi'),
            p(fromJson.name || fromJson.address).class$('pri'),
            p('To').class$('thi'),
            p(toJson.name || toJson.address).class$('pri'),
            // a('', 'Configure via...'),
            h4('Date and time'),
            div(
                p(label('Departure time').att$('for', 'time-kind-departure')),
                input('radio')
                    .checked$(!arrivalInsteadOfDeparture)
                    .id$('time-kind-departure')
                    .att$('name', 'time-kind')
                    .class$('time-kind')
                    .class$('items')
                    .event$('change', timeKindRadioChanged),
            ).class$('checkbox'),
            div(
                p(label('Arrival time').att$('for', 'time-kind-arrival')),
                input('radio')
                    .checked$(arrivalInsteadOfDeparture)
                    .id$('time-kind-arrival')
                    .att$('name', 'time-kind')
                    .class$('time-kind')
                    .class$('items')
                    .event$('change', timeKindRadioChanged),
            ).class$('checkbox'),
            p('Date').class$('thi'),
            p(departureDate.toDateString()).class$('pri'),
            p(label('Time').att$('for', 'time')).class$('thi'),
            p(
                input('time')
                    .id$('time')
                    .att$('value', departureDate.getHours().toString().padStart(2, '0') + ':' + departureDate.getMinutes().toString().padStart(2, '0'))
                    .class$('items')
                    .event$('input', function(event) {
                        var text = event.target.value
                        var splitted = text.toString().split(':')
                        var h = parseInt(splitted[0])
                        var m = parseInt(splitted[1])
                        departureDate.setHours(h, m)
                        updateSearchLink()
                    }),
            ),
            h4('Transport categories'),
            div(
                p(label('ICE, RJX, High speed').class$('product-nationalExpress').att$('for', 'transit-kind-ice')),
                input('checkbox')
                    .checked$(transitKind.ice)
                    .id$('transit-kind-ice')
                    .class$('transit-kind')
                    .class$('items')
                    .event$('change', transitKindCheckChanged),
            ).class$('checkbox'),
            div(
                p(label('IC, EC, RJ').class$('product-national').att$('for', 'transit-kind-ic')),
                input('checkbox')
                    .checked$(transitKind.ic)
                    .id$('transit-kind-ic')
                    .class$('transit-kind')
                    .class$('items')
                    .event$('change', transitKindCheckChanged),
            ).class$('checkbox'),
            div(
                p(label('RE, IRE').class$('product-regionalExpress').att$('for', 'transit-kind-re')),
                input('checkbox')
                    .checked$(transitKind.re)
                    .id$('transit-kind-re')
                    .class$('transit-kind')
                    .class$('items')
                    .event$('change', transitKindCheckChanged),
            ).class$('checkbox'),
            div(
                p(label('RB').class$('product-regional').att$('for', 'transit-kind-rb')),
                input('checkbox')
                    .checked$(transitKind.rb)
                    .id$('transit-kind-rb')
                    .class$('transit-kind')
                    .class$('items')
                    .event$('change', transitKindCheckChanged),
            ).class$('checkbox'),
            div(
                p(label('S-Bahn').class$('product-suburban').att$('for', 'transit-kind-s')),
                input('checkbox')
                    .checked$(transitKind.s)
                    .id$('transit-kind-s')
                    .class$('transit-kind')
                    .class$('items')
                    .event$('change', transitKindCheckChanged),
            ).class$('checkbox'),
            div(
                p(label('U-Bahn').class$('product-subway').att$('for', 'transit-kind-u')),
                input('checkbox')
                    .checked$(transitKind.u)
                    .id$('transit-kind-u')
                    .class$('transit-kind')
                    .class$('items')
                    .event$('change', transitKindCheckChanged),
            ).class$('checkbox'),
            div(
                p(label('Tram, Stadtbahn').class$('product-tram').att$('for', 'transit-kind-tram')),
                input('checkbox')
                    .checked$(transitKind.tram)
                    .id$('transit-kind-tram')
                    .class$('transit-kind')
                    .class$('items')
                    .event$('change', transitKindCheckChanged),
            ).class$('checkbox'),
            div(
                p(label('Bus').class$('product-bus').att$('for', 'transit-kind-bus')),
                input('checkbox')
                    .checked$(transitKind.bus)
                    .id$('transit-kind-bus')
                    .class$('transit-kind')
                    .class$('items')
                    .event$('change', transitKindCheckChanged),
            ).class$('checkbox'),
            div(
                p(label('Ferry').class$('product-ferry').att$('for', 'transit-kind-ferry')),
                input('checkbox')
                    .checked$(transitKind.ferry)
                    .id$('transit-kind-ferry')
                    .class$('transit-kind')
                    .class$('items')
                    .event$('change', transitKindCheckChanged),
            ).class$('checkbox'),
            h4('Start search'),
            a('', 'Search').id$('search-link').class$('items'),
        ).class$('content')
        document.body.insertBefore(contentDiv, footer)
        contentDiv.style.display = 'flex'
        contentDiv.style.flexDirection = 'column'

        updateSearchLink()
    }

    document.querySelectorAll('.lsk').forEach(function (lskElem) {
        lskElem.addEventListener('click', function (e) {
            lsk()
        })
    })
    document.querySelectorAll('.csk').forEach(function (cskElem) {
        cskElem.addEventListener('click', function (e) {
            csk()
        })
    })
    document.body.addEventListener('keydown', function (e) {
        if (e.key == 'SoftLeft') {
            lsk()
        }
        else if (e.key == 'Enter') {
            csk()
        }
    })
})