const DAY_IN_MS = 8.64e+7;

class StopId {
    constructor(stopIdString){
        let [lineId, direction, stopId] = stopIdString.split(/\//)
        this.lineId = lineId
        this.stopId = stopId
        this.direction = direction
    }
}

async function getNextTripJSON(stop_id){
    let res = await fetch(`/api/interface/tcl/next-trips/stops/${encodeURIComponent(stop_id.stopId)}/${encodeURIComponent(stop_id.lineId)}/${stop_id.direction}`);
    if(!res.ok){
        throw new Error(`Server responded with ${res.status} ${res.statusText}`)
    }

    let result = await res.json();

    if(!result.data){
        throw new Error(`Stop ${stop_id.stopId} not found`)
    }

    return result.data[0]
}

async function getStopsJSON(stop_id){
    let res = await fetch(`/api/interface/tcl/lines/${encodeURIComponent(stop_id.lineId)}/stops`);
    if(!res.ok){
        throw new Error(`Server responded with ${res.status} ${res.statusText}`)
    }

    let result = await res.json();

    if(!result.data){
        throw new Error(`Line ${stop_id.lineId} not found`)
    }

    return result.data
}

async function getTimetableJSON(stop_id, date){
    let res = await fetch(`/api/interface/tcl/timetables/${encodeURIComponent(stop_id.stopId)}/${encodeURIComponent(stop_id.lineId)}/${stop_id.direction}?date=${date.getFullYear()}-${(date.getMonth()+1).toString().padStart(2, "0")}-${date.getDate().toString().padStart(2, "0")}`);
    if(!res.ok){
        throw new Error(`Server responded with ${res.status} ${res.statusText}`)
    }

    let result = await res.json();

    if(!result.data){
        throw new Error(`Timetable for ${stop_id.lineId} not found`)
    }

    return result.data
}

async function getLineDetailsJSON(stop_id){
    let res = await fetch(`/api/interface/tcl/lines/${encodeURIComponent(stop_id.lineId)}`);
    if(!res.ok){
        throw new Error(`Server responded with ${res.status} ${res.statusText}`)
    }

    let result = await res.json();

    if(!result.data){
        throw new Error(`Line ${stop_id.lineId} not found`)
    }

    return result.data
}

function getIconURL(stop_id){
    return new URL(`/api/valkyrie/assets/lines/${stop_id.lineId}.svg?type=image%2Fsvg%2Bxml`, window.location).toString()
}

async function getLineDetails(stop_id){
    let line_json = await getLineDetailsJSON(stop_id)

    let route = line_json.routes.find(it => it.direction == stop_id.direction)

    let line = {
        id: stop_id.lineId,
        displayName: route?.name,
        picto: getIconURL(stop_id),
        name: line_json.code,
        direction: route?.name,
        timetable: null
    }

    return line
}

async function getTimetable(stop_id, date){
    let timetable_json = await getTimetableJSON(stop_id, date)
    
    let timetable = []
    for(let scheduled_time of timetable_json.scheduleTimes){
        let time = new Date(scheduled_time.dateTime)
        timetable.push({
            displayHours: time.getHours().toString().padStart(2, "0"),
            displayMinutes: time.getMinutes().toString().padStart(2, "0"),
            displayTime: `${time.getHours().toString().padStart(2, "0")}h${time.getMinutes().toString().padStart(2, "0")}`,
            time
        })
    }

    return timetable
}

/**
 * Get next Bus/Metro/Tram passage of given stop description
 * @param {String} stop_description Stop description string
 * 
 * To get stop description go to https://carte-interactive.tcl.fr/public-transport/lines/
 * then find your line and your stop in this line.
 * Your URL must look like something like this
 * https://carte-interactive.tcl.fr/public-transport/lines/line:SYTNEX:C/forward/stop_point:SYTNEX:10787
 * Stop description is everything after "lines/" ("line:SYTNEX:C/forward/stop_point:SYTNEX:10787" in example above)
 */
export async function getNextPassage(stop_description, options = {
    timetable: +2 // Today and tomorrow
}){
    let stopId = new StopId(stop_description);

    let proms = [
        getLineDetails(stopId),
        getNextTripJSON(stopId),
        getStopsJSON(stopId),
        Promise.resolve([])
    ]

    let timeTableAmount = options?.timetable || +2;
    if(timeTableAmount){
        for(let dayOffset = 0; dayOffset<timeTableAmount; dayOffset++){
            let now = new Date(Date.now()+(dayOffset*DAY_IN_MS))
            proms.push(await getTimetable(stopId, now))
        }
    }

    let [line, next_trip, line_stops, ...all_timetables] = await Promise.all(proms);
    
    console.log(stopId)
    console.log("line", line)
    console.log("next trip", next_trip)
    console.log("stop", line_stops)
    console.log("timetable", all_timetables)

    let line_timetables = []
    for(let timetable of all_timetables){
        line_timetables.push(...timetable)
    }
    line.timetable = line_timetables

    let stop = line_stops.find(it => it.id == stopId.stopId)

    let nextPassage = {
        line,
        displayName: stop?.name,
        displayTime: "<unsupported>",
        time: next_trip.schedules?.[0] ? new Date(next_trip.schedules?.[0].dateTime) : null
    }

    return nextPassage
}