const BASE_MAP_URL = new URL("/public-transport/lines/", document.baseURI)

const DAY_IN_MS = 8.64e+7;

async function waitForElement(iframe, selector, options = {
    timeout: 15000,
    multiple: false
}){
    let timeout = options?.timeout || 15000
    let multiple = options?.multiple || false

    let el = null;
    let startDate = Date.now()

    if(multiple){
        while(!(
            el = iframe.contentWindow.document.querySelectorAll(selector)
        )?.length){
            await new Promise(res => setTimeout(res, 500))
            if(Date.now() > startDate+timeout) {
                throw new Error("Element search timeout")
            }
        }
    } else {
        while((
            el = iframe.contentWindow.document.querySelector(selector)
        ) == null){
            await new Promise(res => setTimeout(res, 500))
            if(Date.now() > startDate+timeout) {
                throw new Error("Element search timeout")
            }
        }
    }

    return el
}

async function spawnIframe(url){
    /** @type {HTMLIFrameElement} */
    let iframe = document.createElement("iframe")
    
    let container = document.createElement("div")
    container.classList.add("thinking")

    container.style.left = Math.round(Math.random()*(window.innerWidth-400))+"px"
    container.style.top = Math.round(Math.random()*(window.innerHeight-350))+"px"

    let img = document.createElement("img")
    img.src = "/lol/math.gif"
    container.append(img)
    
    container.append(iframe)
    
    document.body.append(container)
    
    await navigateIframe(iframe, url)

    return iframe
}

async function navigateIframe(iframe, url){
    let prom = new Promise(res => iframe.addEventListener("load", res(), {once: true}))
    iframe.src = new URL(url, BASE_MAP_URL).toString()
    await prom

    return iframe
}

async function getLineDetails(iframe){
    let lineElement = await waitForElement(iframe, `[class|="content"] [class|="pictoAndDirection"]`)
    let linePictoElement = await waitForElement(iframe, `[class|="content"] [class|="linePictoSvg"]`)
    let directionTextElement = await waitForElement(iframe, `[class|="content"] [class|="directionText"]`)

    let line = {
        displayName: lineElement.getAttribute("aria-label"),
        picto: linePictoElement.src,
        name: linePictoElement.getAttribute("aria-label"),
        direction: directionTextElement.innerText,
        timetable: null
    }

    return line
}

async function getStopTimeTable(iframe, stop_description, amount=1){
    let timetable = []
    for(let dayOffset = 0; dayOffset<amount; dayOffset++){

        let now = new Date(Date.now()+(dayOffset*DAY_IN_MS))
        await navigateIframe(iframe, "./"+stop_description+`/timetable?date=${now.getFullYear()}-${(now.getMonth()+1).toString().padStart(2, "0")}-${(now.getDate()).toString().padStart(2, "0")}`)

        let timeTableElList = await waitForElement(iframe, `[class|="content"] [class|="timeTableContainer"] table`, {multiple: true});
        for(let timeTableEl of timeTableElList){
            let trancheHoraires = timeTableEl.querySelectorAll("thead tr:first-child th")
            for(let i = 0; i< trancheHoraires.length; i++){
                let el = trancheHoraires[i]
                let hours = parseInt(el.innerText.trim())
                if(Number.isFinite(hours)){
                    let allHoraires = timeTableEl.querySelectorAll(`tbody tr td:nth-child(${i+1})`)
                    for(let hel of allHoraires){
                        let minutes = parseInt(hel.innerText.trim())
                        if(Number.isFinite(minutes)){
                            timetable.push({
                                displayHours: el.innerText,
                                displayMinutes: hel.innerText,
                                displayTime: `${el.innerText}${hel.innerText}`,
                                time: new Date(
                                    now.getFullYear(),
                                    now.getMonth(),
                                    now.getDate(),
                                    hours,
                                    minutes
                                )
                            })
                        }
                    }
                }
            }
        }
    }
    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 iframe = await spawnIframe("./"+stop_description)

    let nextPassageElement = await waitForElement(iframe, `[class|="content"] [class|="stopCard"] [class|="schedule"]`);
    let stopName = await waitForElement(iframe, `[class|="content"] [class|="stopCard"] [class|="nameStop"]`);

    let line = await getLineDetails(iframe, stop_description)

    let timetable = []
    let timeTableAmount = options?.timetable || +2;
    if(timeTableAmount){
        timetable = await getStopTimeTable(iframe, stop_description, timeTableAmount)
    } else {
        timetable = null
    }
    line.timetable = timetable

    let nextPassage = {
        line,
        displayName: stopName.innerText,
        displayTime: nextPassageElement.innerText
    }

    {
        let timeText = nextPassageElement.innerText.trim();
        let time;
        if(timeText.endsWith("min")){
            time = new Date(Date.now() + parseInt(timeText)*60000)
        } else {
            let match = timeText.match(/^(\d+):(\d+)/)
            if(match){
                let now = new Date()
                time = new Date(
                    now.getFullYear(),
                    now.getMonth(),
                    now.getDate(),
                    parseInt(match[1]),
                    parseInt(match[2])
                )

                if(time.getTime() < Date.now()){
                    time.setTime(time.getTime() + DAY_IN_MS)
                }
            }
        }
        nextPassage.time = time
    }

    setTimeout(() => {
        iframe.parentElement.remove()
    }, Math.random()*1000)

    return nextPassage
}