import maplibregl from "maplibre-gl"

const trackingMinTimeMs = 5000

const defaultStyle = {
  version: 8,
  sources: {
    osm: {
      type: "raster",
      tiles: [document.documentElement.dataset.mapTileUrl],
      tileSize: 256,
      attribution: "© OpenStreetMap contributors"
    }
  },
  layers: [{id: "osm", type: "raster", source: "osm"}]
}

const markerPoints = element => {
  try {
    const points = JSON.parse(element.dataset.items || element.dataset.markers || "[]")

    if (!Array.isArray(points)) return []

    return points.filter(point =>
      Number.isFinite(point?.longitude) && Number.isFinite(point?.latitude)
    )
  } catch (_error) {
    return []
  }
}

const emptyFeatureCollection = () => ({type: "FeatureCollection", features: []})

const areaPolygon = point => {
  const {longitude, latitude, radius_meters: radiusMeters} = point
  const earthRadiusMeters = 6371008.8
  const angularDistance = radiusMeters / earthRadiusMeters
  const latitudeRadians = latitude * Math.PI / 180
  const longitudeRadians = longitude * Math.PI / 180
  const coordinates = []

  for (let step = 0; step <= 64; step += 1) {
    const bearing = step / 64 * Math.PI * 2
    const pointLatitude = Math.asin(
      Math.sin(latitudeRadians) * Math.cos(angularDistance) +
      Math.cos(latitudeRadians) * Math.sin(angularDistance) * Math.cos(bearing)
    )
    const pointLongitude = longitudeRadians + Math.atan2(
      Math.sin(bearing) * Math.sin(angularDistance) * Math.cos(latitudeRadians),
      Math.cos(angularDistance) - Math.sin(latitudeRadians) * Math.sin(pointLatitude)
    )

    coordinates.push([pointLongitude * 180 / Math.PI, pointLatitude * 180 / Math.PI])
  }

  return {
    type: "Feature",
    id: point.id,
    properties: {
      id: point.id,
      title: point.title || "",
      location: point.location || "",
      type: point.type || "request"
    },
    geometry: {type: "Polygon", coordinates: [coordinates]}
  }
}

const areaFeatureCollection = points => ({
  type: "FeatureCollection",
  features: points
    .filter(point => !point.exact && Number.isFinite(point.radius_meters))
    .map(areaPolygon)
})

const clusterFeatureCollection = points => ({
  type: "FeatureCollection",
  features: points
    .filter(point => point.type === "cluster")
    .map(point => ({
      type: "Feature",
      id: point.id,
      properties: {
        id: point.id,
        count: point.count,
        urgent_count: point.urgent_count || 0
      },
      geometry: {type: "Point", coordinates: [point.longitude, point.latitude]}
    }))
})

const mapViewport = map => {
  const bounds = map.getBounds()
  const container = map.getContainer()
  if (container.clientWidth < 160 || container.clientHeight < 160) return null

  return {
    west: Math.max(-180, Math.min(180, bounds.getWest())),
    south: Math.max(-85.05112878, Math.min(85.05112878, bounds.getSouth())),
    east: Math.max(-180, Math.min(180, bounds.getEast())),
    north: Math.max(-85.05112878, Math.min(85.05112878, bounds.getNorth())),
    zoom: map.getZoom(),
    width: Math.round(container.clientWidth),
    height: Math.round(container.clientHeight)
  }
}

const savedViewport = element => {
  try {
    const viewport = JSON.parse(element.dataset.viewport || "")
    if (!viewport || typeof viewport !== "object") return null

    const west = Number(viewport.west)
    const south = Number(viewport.south)
    const east = Number(viewport.east)
    const north = Number(viewport.north)

    if (![west, south, east, north].every(Number.isFinite)) return null
    return {west, south, east, north}
  } catch (_error) {
    return null
  }
}

const extendBoundsWithFeature = (bounds, feature) => {
  feature.geometry.coordinates[0].forEach(coordinate => bounds.extend(coordinate))
}

const privacySafeAreaCenter = (latitude, longitude, radiusMeters) => {
  const latitudeStep = radiusMeters * Math.SQRT2 / 111320
  const longitudeScale = Math.max(Math.cos(latitude * Math.PI / 180), 0.2)
  const longitudeStep = latitudeStep / longitudeScale

  return {
    latitude: Math.round(latitude / latitudeStep) * latitudeStep,
    longitude: Math.round(longitude / longitudeStep) * longitudeStep
  }
}

const createAidMap = element => {
  const state = {
    element,
    map: null,
    active: true,
    viewportFrame: null,
    resizeFrame: null,
    resizeObserver: null,
    markers: [],
    markerElements: new Map(),
    initializedViewport: false,
    areaSourceId: `${element.id || "aid-map"}-areas`,
    areaFillId: `${element.id || "aid-map"}-area-fill`,
    areaLineId: `${element.id || "aid-map"}-area-line`,
    areaSelectedId: `${element.id || "aid-map"}-area-selected`,
    clusterSourceId: `${element.id || "aid-map"}-clusters`,
    clusterCircleId: `${element.id || "aid-map"}-cluster-circle`,
    clusterCountId: `${element.id || "aid-map"}-cluster-count`
  }

  state.markLoading = () => {
    if (state.element.dataset.mapReady !== "true") {
      state.element.dataset.mapReady = "false"
    }
  }

  state.markReady = () => {
    state.element.dataset.mapReady = "true"
  }

  state.showUnavailable = () => {
    state.map = null
    state.element.dataset.mapUnavailable = "true"
    state.markReady()

    if (state.element.dataset.demoMap !== "true") {
      const fallback = document.createElement("p")
      fallback.className = "grid h-full place-items-center p-6 text-center text-sm"
      fallback.dataset.mapFallback = "true"
      fallback.textContent = state.element.dataset.mapUnavailableLabel
      state.element.replaceChildren(fallback)
      return
    }

    const fallback = document.createElement("div")
    fallback.className = "home-demo-map-fallback"
    fallback.dataset.mapFallback = "true"

    const note = document.createElement("p")
    note.className = "home-demo-map-fallback-note"
    note.textContent = state.element.dataset.mapUnavailableLabel
    fallback.append(note)

    const points = document.createElement("div")
    points.className = "home-demo-map-fallback-points"

    markerPoints(state.element).forEach((point, index) => {
      const item = document.createElement("div")
      item.className = "home-demo-map-fallback-point"

      const marker = document.createElement("span")
      marker.className = "home-demo-map-fallback-marker"
      marker.setAttribute("aria-hidden", "true")
      marker.textContent = String(index + 1)

      const copy = document.createElement("span")
      copy.className = "home-demo-map-fallback-copy"

      const title = document.createElement("strong")
      title.textContent = point.title || ""

      const location = document.createElement("small")
      location.textContent = point.location || ""

      copy.append(title, location)
      item.append(marker, copy)
      points.append(item)
    })

    fallback.append(points)
    state.element.replaceChildren(fallback)
  }

  state.popupContent = point => {
    const content = document.createElement("div")
    content.className = "request-map-popup"

    const title = document.createElement("strong")
    title.textContent = point.title || ""
    content.append(title)

    const location = document.createElement("small")
    location.textContent = point.location || ""
    content.append(location)

    if (point.id) {
      const link = document.createElement("a")
      link.href = `/requests/${encodeURIComponent(point.id)}`
      link.textContent = state.element.dataset.requestLabel || "Open request"
      content.append(link)
    }

    return content
  }

  state.highlightRequest = id => {
    state.markerElements.forEach((element, requestId) => {
      element.classList.toggle("is-selected", requestId === id)
    })

    if (state.map?.getLayer(state.areaSelectedId)) {
      state.map.setFilter(state.areaSelectedId, ["==", ["get", "id"], id || ""])
    }
  }

  state.selectRequest = id => {
    state.highlightRequest(id)
    window.dispatchEvent(new CustomEvent("wnh:request-selected", {detail: {id}}))
  }

  state.resize = () => {
    if (!state.active || !state.map) return

    const {width, height} = state.element.getBoundingClientRect()
    if (width < 160 || height < 160) return

    if (state.resizeFrame !== null) window.cancelAnimationFrame(state.resizeFrame)
    state.resizeFrame = window.requestAnimationFrame(() => {
      state.resizeFrame = null
      if (!state.active || !state.map) return

      const current = state.element.getBoundingClientRect()
      if (current.width >= 160 && current.height >= 160) state.map.resize()
    })
  }

  state.applySavedViewport = () => {
    if (!state.active || !state.map) return

    const viewport = savedViewport(state.element)
    const serialized = viewport ? JSON.stringify(viewport) : ""
    if (!viewport || state.appliedViewport === serialized) return

    state.appliedViewport = serialized
    state.map.fitBounds(
      [[viewport.west, viewport.south], [viewport.east, viewport.north]],
      {padding: 0, duration: 0}
    )
  }

  state.renderMarkers = () => {
    if (!state.map) return

    state.markers.forEach(marker => marker.remove())
    state.markers = []
    state.markerElements.clear()

    const points = markerPoints(state.element)
    const exactPoints = points.filter(
      point => point.type !== "cluster" && (point.exact || !Number.isFinite(point.radius_meters))
    )
    const areaFeatures = areaFeatureCollection(points)
    const clusterFeatures = clusterFeatureCollection(points)

    if (state.map.isStyleLoaded()) {
      const areaSource = state.map.getSource(state.areaSourceId)

      if (areaSource) {
        areaSource.setData(areaFeatures)
      } else {
        state.map.addSource(state.areaSourceId, {type: "geojson", data: areaFeatures})
        state.map.addLayer({
          id: state.areaFillId,
          type: "fill",
          source: state.areaSourceId,
          paint: {"fill-color": "#278467", "fill-opacity": 0.18}
        })
        state.map.addLayer({
          id: state.areaLineId,
          type: "line",
          source: state.areaSourceId,
          paint: {
            "line-color": "#16725b",
            "line-width": 2,
            "line-dasharray": [2, 2]
          }
        })
        state.map.addLayer({
          id: state.areaSelectedId,
          type: "line",
          source: state.areaSourceId,
          filter: ["==", ["get", "id"], ""],
          paint: {"line-color": "#d6573b", "line-width": 5}
        })

        state.map.on("mouseenter", state.areaFillId, () => {
          state.map.getCanvas().style.cursor = "pointer"
        })
        state.map.on("mouseleave", state.areaFillId, () => {
          state.map.getCanvas().style.cursor = ""
        })
        state.map.on("click", state.areaFillId, event => {
          const properties = event.features?.[0]?.properties
          if (!properties?.id) return

          state.selectRequest(properties.id)
          new maplibregl.Popup({offset: 12})
            .setLngLat(event.lngLat)
            .setDOMContent(state.popupContent(properties))
            .addTo(state.map)
        })
      }

    }

    exactPoints.forEach(point => {
      const popup = new maplibregl.Popup({offset: 18}).setDOMContent(state.popupContent(point))
      const marker = new maplibregl.Marker({color: point.exact ? "#d6573b" : "#278467"})
        .setLngLat([point.longitude, point.latitude])
        .setPopup(popup)
        .addTo(state.map)

      const markerElement = marker.getElement()
      markerElement.dataset.requestId = point.id
      markerElement.addEventListener("click", () => state.selectRequest(point.id))
      state.markerElements.set(point.id, markerElement)
      state.markers.push(marker)
    })

    points.filter(point => point.type === "cluster").forEach(point => {
      const element = document.createElement("button")
      element.type = "button"
      element.className = "request-map-cluster"
      element.classList.toggle("is-urgent", Number(point.urgent_count) > 0)
      element.textContent = String(point.count)
      element.setAttribute("aria-label", `${point.count} requests`)
      element.addEventListener("click", event => {
        event.stopPropagation()
        state.map.easeTo({
          center: [point.longitude, point.latitude],
          zoom: Math.min(state.map.getZoom() + 2, 20)
        })
      })

      const marker = new maplibregl.Marker({element})
        .setLngLat([point.longitude, point.latitude])
        .addTo(state.map)

      state.markers.push(marker)
    })

    if (points.length > 0 && state.element.dataset.autoFit !== "false") {
      const bounds = new maplibregl.LngLatBounds()
      exactPoints.forEach(point => bounds.extend([point.longitude, point.latitude]))
      areaFeatures.features.forEach(feature => extendBoundsWithFeature(bounds, feature))
      clusterFeatures.features.forEach(feature => bounds.extend(feature.geometry.coordinates))
      state.map.fitBounds(bounds, {padding: 52, maxZoom: 13, duration: 0})
    }
  }

  state.mount = () => {
    state.markLoading()
    const demoMap = state.element.dataset.demoMap === "true"

    if (!supportsMapCanvas()) {
      state.showUnavailable()
      return
    }

    try {
      state.map = new maplibregl.Map({
        container: state.element,
        style: defaultStyle,
        center: [30.5234, 50.4501],
        zoom: 5,
        attributionControl: true,
        renderWorldCopies: false,
        maxBounds: [[-180, -85.05112878], [180, 85.05112878]],
        trackResize: false,
        dragRotate: !demoMap,
        pitchWithRotate: !demoMap,
        scrollZoom: !demoMap
      })
    } catch (_error) {
      state.showUnavailable()
      return
    }

    if (demoMap) state.map.touchZoomRotate.disableRotation()

    state.map.addControl(
      new maplibregl.NavigationControl({showCompass: !demoMap}),
      demoMap ? "bottom-right" : "top-right"
    )

    if (state.element.dataset.discoveryMap === "true" && navigator.geolocation) {
      state.map.addControl(
        new maplibregl.GeolocateControl({
          positionOptions: {enableHighAccuracy: false},
          trackUserLocation: false,
          showUserLocation: false,
          fitBoundsOptions: {maxZoom: 13}
        }),
        "top-right"
      )
    }

    state.onLoad = () => {
      if (!state.active || !state.map) return

      state.markReady()
      state.applySavedViewport()
      state.renderMarkers()

      state.viewportFrame = window.requestAnimationFrame(() => {
        state.viewportFrame = null
        if (!state.active || !state.map) return

        state.initializedViewport = true

        if (state.element.dataset.discoveryMap === "true" && !savedViewport(state.element)) {
          const viewport = mapViewport(state.map)
          if (viewport) state.onInitializeViewport?.(viewport)
        }
      })
    }

    state.onMoveEnd = () => {
      if (!state.initializedViewport || state.element.dataset.discoveryMap !== "true") return
      const viewport = mapViewport(state.map)
      if (viewport) state.onViewportChange?.(viewport)
    }

    state.onRequestHighlight = event => state.highlightRequest(event.detail?.id)

    state.map.on("dataloading", state.markLoading)
    state.map.on("load", state.onLoad)
    state.map.on("idle", state.markReady)
    state.map.on("moveend", state.onMoveEnd)
    window.addEventListener("wnh:request-highlight", state.onRequestHighlight)
    if ("ResizeObserver" in window) {
      state.resizeObserver = new ResizeObserver(state.resize)
      state.resizeObserver.observe(state.element)
    }
    state.renderMarkers()
  }

  state.destroy = () => {
    state.active = false
    if (state.viewportFrame !== null) window.cancelAnimationFrame(state.viewportFrame)
    if (state.resizeFrame !== null) window.cancelAnimationFrame(state.resizeFrame)
    state.resizeObserver?.disconnect()
    state.map?.off("dataloading", state.markLoading)
    state.map?.off("load", state.onLoad)
    state.map?.off("idle", state.markReady)
    state.map?.off("moveend", state.onMoveEnd)
    window.removeEventListener("wnh:request-highlight", state.onRequestHighlight)
    state.map?.remove()
    state.map = null
  }

  return state
}

export const mountStaticAidMaps = root => {
  root.querySelectorAll("[data-static-aid-map]").forEach(element => {
    if (element.dataset.staticMapMounted === "true") return

    const mount = () => {
      element.dataset.staticMapMounted = "true"
      element._aidMap = createAidMap(element)
      element._aidMap.mount()
    }

    if (!("IntersectionObserver" in window)) {
      mount()
      return
    }

    const observer = new IntersectionObserver(entries => {
      if (!entries.some(entry => entry.isIntersecting)) return

      observer.disconnect()
      mount()
    }, {rootMargin: "240px"})

    observer.observe(element)
  })
}

export const Hooks = {
  DateTimePicker: {
    mounted() {
      this.hiddenInput = this.el.querySelector("[data-datetime-value]")
      this.unusedInput = this.el.querySelector("[data-datetime-unused]")
      this.dateInput = this.el.querySelector("[data-datetime-date]")
      this.timeInput = this.el.querySelector("[data-datetime-time]")
      this.timezoneLabel = this.el.querySelector("[data-datetime-timezone]")
      this.quickButtons = [...this.el.querySelectorAll("[data-datetime-offset]")]

      const pad = value => String(value).padStart(2, "0")
      const localParts = date => ({
        date: `${date.getFullYear()}-${pad(date.getMonth() + 1)}-${pad(date.getDate())}`,
        time: `${pad(date.getHours())}:${pad(date.getMinutes())}`
      })
      const utcValue = date =>
        `${date.getUTCFullYear()}-${pad(date.getUTCMonth() + 1)}-${pad(date.getUTCDate())}` +
        `T${pad(date.getUTCHours())}:${pad(date.getUTCMinutes())}`

      this.parseUtc = value => {
        const match = String(value || "").match(
          /^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2})(?::\d{2})?/
        )
        if (!match) return null

        const [, year, month, day, hour, minute] = match
        const date = new Date(Date.UTC(year, Number(month) - 1, day, hour, minute))
        return Number.isNaN(date.getTime()) ? null : date
      }

      this.applyLocalDate = date => {
        const parts = localParts(date)
        this.dateInput.value = parts.date
        this.timeInput.value = parts.time
        this.updateMinimum()
      }

      this.updateMinimum = () => {
        const minimum = this.parseUtc(this.el.dataset.minValue)
        if (!minimum) return

        const parts = localParts(minimum)
        this.dateInput.min = parts.date
        this.timeInput.min = this.dateInput.value === parts.date ? parts.time : ""
      }

      this.syncHidden = () => {
        this.updateMinimum()

        let value = ""
        if (this.dateInput.value && this.timeInput.value) {
          const [year, month, day] = this.dateInput.value.split("-").map(Number)
          const [hour, minute] = this.timeInput.value.split(":").map(Number)
          const date = new Date(year, month - 1, day, hour, minute)
          if (!Number.isNaN(date.getTime())) value = utcValue(date)
        }

        if (this.hiddenInput.value === value) return
        this.hiddenInput.value = value
        this.hiddenInput.dispatchEvent(new Event("input", {bubbles: true}))
      }

      this.syncUserInput = () => {
        if (this.unusedInput) this.unusedInput.disabled = true
        this.syncHidden()
      }

      this.setQuickTime = event => {
        const minutes = Number(event.currentTarget.dataset.datetimeOffset)
        if (!Number.isFinite(minutes)) return

        const date = new Date(Date.now() + minutes * 60_000)
        date.setSeconds(0, 0)
        this.applyLocalDate(date)
        this.syncUserInput()
      }

      this.dateInput.addEventListener("input", this.syncUserInput)
      this.timeInput.addEventListener("input", this.syncUserInput)
      this.quickButtons.forEach(button => button.addEventListener("click", this.setQuickTime))

      const initial = this.parseUtc(this.hiddenInput.value)
      if (initial) this.applyLocalDate(initial)
      this.updateMinimum()

      if (this.timezoneLabel) {
        this.timezoneLabel.textContent =
          Intl.DateTimeFormat().resolvedOptions().timeZone || "UTC"
      }
    },
    destroyed() {
      this.dateInput?.removeEventListener("input", this.syncUserInput)
      this.timeInput?.removeEventListener("input", this.syncUserInput)
      this.quickButtons?.forEach(button => button.removeEventListener("click", this.setQuickTime))
    }
  },

  LocalTime: {
    mounted() {
      const value = this.el.dateTime || this.el.dataset.datetime
      const date = new Date(value)
      if (Number.isNaN(date.getTime())) return

      this.el.textContent = new Intl.DateTimeFormat(undefined, {
        dateStyle: "medium",
        timeStyle: "short"
      }).format(date)
      this.el.title = date.toISOString()
    }
  },

  ChatMessages: {
    mounted() {
      this.wasNearBottom = true
      this.el.scrollTop = this.el.scrollHeight
      this.isIntersecting = false
      this.markingRead = false
      this.recordPosition = () => {
        this.wasNearBottom =
          this.el.scrollHeight - this.el.scrollTop - this.el.clientHeight < 80
      }
      this.markRead = () => {
        if (
          this.el.dataset.readReceipts !== "true" ||
          this.el.dataset.hasUnread !== "true" ||
          document.visibilityState !== "visible" ||
          !this.isIntersecting ||
          this.markingRead
        ) return

        this.markingRead = true
        this.pushEvent("mark-messages-read", {}, () => {
          this.markingRead = false
        })
      }
      this.visibilityChanged = () => this.markRead()
      this.el.addEventListener("scroll", this.recordPosition, {passive: true})
      document.addEventListener("visibilitychange", this.visibilityChanged)

      if (this.el.dataset.readReceipts === "true" && "IntersectionObserver" in window) {
        this.visibilityObserver = new IntersectionObserver(entries => {
          this.isIntersecting = entries.some(entry => entry.isIntersecting)
          this.markRead()
        }, {threshold: 0.1})
        this.visibilityObserver.observe(this.el)
      } else {
        this.isIntersecting = true
        this.markRead()
      }
    },
    beforeUpdate() {
      this.recordPosition()
      const firstMessage = this.el.querySelector("[data-chat-message]")
      this.anchorId = firstMessage?.id
      this.anchorOffset = firstMessage?.offsetTop
    },
    updated() {
      if (this.wasNearBottom) {
        this.el.scrollTop = this.el.scrollHeight
      } else if (this.anchorId) {
        const anchor = document.getElementById(this.anchorId)
        if (anchor && Number.isFinite(this.anchorOffset)) {
          this.el.scrollTop += anchor.offsetTop - this.anchorOffset
        }
      }
      this.markRead()
    },
    destroyed() {
      this.el.removeEventListener("scroll", this.recordPosition)
      document.removeEventListener("visibilitychange", this.visibilityChanged)
      this.visibilityObserver?.disconnect()
    }
  },

  ChatComposer: {
    mounted() {
      this.resize = () => {
        this.el.style.height = "auto"
        this.el.style.height = `${Math.min(this.el.scrollHeight, 160)}px`
      }
      this.submitOnEnter = event => {
        if (event.key !== "Enter" || event.shiftKey || event.isComposing) return
        event.preventDefault()
        this.el.form?.requestSubmit()
      }
      this.reset = () => window.requestAnimationFrame(this.resize)

      this.el.addEventListener("input", this.resize)
      this.el.addEventListener("keydown", this.submitOnEnter)
      this.el.form?.addEventListener("reset", this.reset)
      this.resize()
    },
    destroyed() {
      this.el.removeEventListener("input", this.resize)
      this.el.removeEventListener("keydown", this.submitOnEnter)
      this.el.form?.removeEventListener("reset", this.reset)
    }
  },

  CopyToClipboard: {
    mounted() {
      this.resetLabel = () => {
        this.el.textContent = this.el.dataset.defaultLabel
      }

      this.copy = async () => {
        const value = this.el.dataset.copyValue || ""

        const fallbackCopy = () => {
          const input = document.createElement("textarea")
          input.value = value
          input.setAttribute("readonly", "")
          input.style.position = "fixed"
          input.style.opacity = "0"
          document.body.append(input)
          input.select()
          const copied = document.execCommand("copy")
          input.remove()

          if (!copied) throw new Error("Clipboard copy failed")
        }

        try {
          if (navigator.clipboard?.writeText) {
            await navigator.clipboard.writeText(value)
          } else {
            fallbackCopy()
          }
          this.el.textContent = this.el.dataset.copiedLabel
        } catch (_error) {
          try {
            fallbackCopy()
            this.el.textContent = this.el.dataset.copiedLabel
          } catch (_fallbackError) {
            this.el.textContent = this.el.dataset.errorLabel
          }
        }

        window.clearTimeout(this.labelTimer)
        this.labelTimer = window.setTimeout(this.resetLabel, 1800)
      }

      this.el.addEventListener("click", this.copy)
    },
    destroyed() {
      this.el.removeEventListener("click", this.copy)
      window.clearTimeout(this.labelTimer)
    }
  },

  HandoverCode: {
    mounted() {
      this.normalize = () => {
        this.el.value = this.el.value.replace(/[^0-9]/g, "").slice(0, 6)
      }

      this.el.addEventListener("input", this.normalize)
    },
    destroyed() {
      this.el.removeEventListener("input", this.normalize)
    }
  },

  AidMap: {
    mounted() {
      this.aidMap = createAidMap(this.el)
      this.el._aidMap = this.aidMap
      this.aidMap.onInitializeViewport = viewport =>
        this.pushEvent("initialize-map-area", viewport)
      this.aidMap.onViewportChange = viewport =>
        this.pushEvent("map-viewport-change", viewport)
      this.aidMap.mount()
    },
    updated() {
      this.aidMap.applySavedViewport()
      this.aidMap.renderMarkers()
      this.aidMap.resize()
    },
    destroyed() {
      this.aidMap.destroy()
      delete this.el._aidMap
    }
  },

  RequestDiscovery: {
    mounted() {
      this.storageKey = "wnh:request-discovery-view"
      this.allowedViews = ["list", "split", "map"]

      this.resizeMap = () => {
        document.querySelector("#request-map")?._aidMap?.resize()
      }

      this.persistView = () => {
        const view = this.el.dataset.viewMode
        if (!this.allowedViews.includes(view)) return

        try {
          window.localStorage.setItem(this.storageKey, view)
        } catch (_error) {
          // The URL still keeps the selected mode when storage is unavailable.
        }
      }

      this.onPointerOver = event => {
        const card = event.target.closest("[data-discovery-card]")
        if (!card || !this.el.contains(card)) return

        window.dispatchEvent(
          new CustomEvent("wnh:request-highlight", {detail: {id: card.dataset.requestId}})
        )
      }

      this.onPointerOut = event => {
        const card = event.target.closest("[data-discovery-card]")
        if (!card || card.contains(event.relatedTarget)) return
        window.dispatchEvent(new CustomEvent("wnh:request-highlight", {detail: {id: null}}))
      }

      this.onRequestSelected = event => {
        this.el.querySelectorAll("[data-discovery-card]").forEach(card => {
          card.classList.toggle("is-selected", card.dataset.requestId === event.detail?.id)
        })

        const selected = this.el.querySelector(
          `[data-discovery-card][data-request-id="${CSS.escape(String(event.detail?.id || ""))}"]`
        )

        if (selected && this.el.dataset.viewMode !== "map") {
          selected.scrollIntoView({block: "nearest", behavior: "smooth"})
        }
      }

      this.el.addEventListener("pointerover", this.onPointerOver)
      this.el.addEventListener("pointerout", this.onPointerOut)
      window.addEventListener("wnh:request-selected", this.onRequestSelected)

      let savedView = null

      try {
        savedView = window.localStorage.getItem(this.storageKey)
      } catch (_error) {
        savedView = null
      }

      if (
        this.el.dataset.viewExplicit !== "true" &&
        this.allowedViews.includes(savedView) &&
        savedView !== this.el.dataset.viewMode
      ) {
        this.pushEvent("restore-view-mode", {view: savedView})
      } else {
        this.persistView()
      }

      this.resizeMap()
    },
    updated() {
      this.persistView()
      this.resizeMap()
    },
    destroyed() {
      this.el.removeEventListener("pointerover", this.onPointerOver)
      this.el.removeEventListener("pointerout", this.onPointerOut)
      window.removeEventListener("wnh:request-selected", this.onRequestSelected)
    }
  },

  RequestLocationPicker: {
    mounted() {
      this.map = null
      this.marker = null
      this.markerMode = null
      this.mapLoaded = false
      this.mapUnavailable = false
      this.areaSourceId = `${this.el.id}-selection-area`
      this.areaFillId = `${this.el.id}-selection-fill`
      this.areaLineId = `${this.el.id}-selection-line`

      this.cacheElements = () => {
        this.mapElement = this.el.querySelector(this.el.dataset.mapTarget)
        this.latitudeInput = this.el.querySelector(this.el.dataset.latitudeTarget)
        this.longitudeInput = this.el.querySelector(this.el.dataset.longitudeTarget)
        this.statusElement = this.el.querySelector(this.el.dataset.statusTarget)
      }

      this.renderMapUnavailable = () => {
        if (!this.mapElement) return

        this.mapElement.dataset.mapUnavailable = "true"
        this.mapElement.textContent = this.mapElement.dataset.mapUnavailableLabel
      }

      this.mode = () =>
        this.el.querySelector("[data-location-mode-input]:checked")?.value ||
        this.el.dataset.locationMode ||
        "approximate_public"

      this.radius = () => {
        const value = Number(
          this.el.querySelector("[data-location-radius-input]:checked")?.value || 1000
        )
        return [500, 1000, 2000].includes(value) ? value : 1000
      }

      this.coordinates = () => {
        const latitudeValue = String(this.latitudeInput?.value || "").trim()
        const longitudeValue = String(this.longitudeInput?.value || "").trim()
        if (latitudeValue === "" || longitudeValue === "") return null

        const latitude = Number(latitudeValue)
        const longitude = Number(longitudeValue)

        if (
          !Number.isFinite(latitude) ||
          !Number.isFinite(longitude) ||
          latitude < -90 ||
          latitude > 90 ||
          longitude < -180 ||
          longitude > 180
        ) return null

        return {latitude, longitude}
      }

      this.setStatus = message => {
        if (this.statusElement) this.statusElement.textContent = message
      }

      this.setSelectionStatus = () => {
        if (!this.coordinates()) {
          this.setStatus(this.el.dataset.mapReadyLabel)
          return
        }

        this.setStatus(
          this.mode() === "approximate_public"
            ? this.el.dataset.areaSelectedLabel
            : this.el.dataset.pointSelectedLabel
        )
      }

      this.focusSelection = () => {
        const coordinates = this.coordinates()
        if (!coordinates || !this.map) return

        this.map.flyTo({
          center: [coordinates.longitude, coordinates.latitude],
          zoom: this.mode() === "exact_public" ? 15 : 13
        })
      }

      this.notifyCoordinatesChanged = () => {
        this.longitudeInput?.dispatchEvent(new Event("input", {bubbles: true}))
      }

      this.setCoordinates = ({latitude, longitude}, {notify = true, center = false} = {}) => {
        if (!this.latitudeInput || !this.longitudeInput) return

        this.latitudeInput.value = latitude.toFixed(6)
        this.longitudeInput.value = longitude.toFixed(6)
        this.renderSelection()

        if (center && this.map) {
          this.map.flyTo({center: [longitude, latitude], zoom: this.mode() === "exact_public" ? 15 : 13})
        }

        if (notify) this.notifyCoordinatesChanged()
      }

      this.clearCoordinates = ({notify = false} = {}) => {
        if (this.latitudeInput) this.latitudeInput.value = ""
        if (this.longitudeInput) this.longitudeInput.value = ""
        this.renderSelection()
        if (notify) this.notifyCoordinatesChanged()
      }

      this.ensureAreaLayers = () => {
        if (!this.mapLoaded || this.map.getSource(this.areaSourceId)) return

        this.map.addSource(this.areaSourceId, {type: "geojson", data: emptyFeatureCollection()})
        this.map.addLayer({
          id: this.areaFillId,
          type: "fill",
          source: this.areaSourceId,
          paint: {"fill-color": "#278467", "fill-opacity": 0.2}
        })
        this.map.addLayer({
          id: this.areaLineId,
          type: "line",
          source: this.areaSourceId,
          paint: {
            "line-color": "#16725b",
            "line-width": 2,
            "line-dasharray": [2, 2]
          }
        })
      }

      this.setAreaData = data => {
        if (!this.mapLoaded) return
        this.ensureAreaLayers()
        this.map.getSource(this.areaSourceId)?.setData(data)
      }

      this.removeMarker = () => {
        this.marker?.remove()
        this.marker = null
        this.markerMode = null
      }

      this.ensureSelectionMarker = (coordinates, mode) => {
        if (this.marker && this.markerMode !== mode) this.removeMarker()

        if (!this.marker) {
          this.markerMode = mode
          this.marker = new maplibregl.Marker({
            color: mode === "approximate_public" ? "#16725b" : "#d6573b",
            draggable: true
          })
            .setLngLat([coordinates.longitude, coordinates.latitude])
            .addTo(this.map)

          const markerElement = this.marker.getElement()
          markerElement.setAttribute(
            "aria-label",
            mode === "approximate_public"
              ? this.el.dataset.areaMarkerLabel
              : this.el.dataset.pointMarkerLabel
          )
          markerElement.setAttribute(
            "title",
            mode === "approximate_public"
              ? this.el.dataset.areaMarkerLabel
              : this.el.dataset.pointMarkerLabel
          )

          this.marker.on("drag", () => {
            const point = this.marker.getLngLat()

            if (this.latitudeInput) this.latitudeInput.value = point.lat.toFixed(6)
            if (this.longitudeInput) this.longitudeInput.value = point.lng.toFixed(6)

            if (this.markerMode === "approximate_public") {
              this.setAreaData(areaFeatureCollection([{
                latitude: point.lat,
                longitude: point.lng,
                exact: false,
                radius_meters: this.radius()
              }]))
            }
          })

          this.marker.on("dragend", () => {
            const point = this.marker.getLngLat()
            this.setCoordinates({latitude: point.lat, longitude: point.lng})
            this.setSelectionStatus()
          })
        } else {
          this.marker.setLngLat([coordinates.longitude, coordinates.latitude])
        }
      }

      this.renderSelection = () => {
        const mode = this.mode()
        const coordinates = this.coordinates()
        this.el.dataset.locationMode = mode

        if (!this.mapLoaded) return

        if (mode === "hidden") {
          this.removeMarker()
          this.setAreaData(emptyFeatureCollection())
          return
        }

        if (!coordinates) {
          this.removeMarker()
          this.setAreaData(emptyFeatureCollection())
          return
        }

        if (mode === "approximate_public") {
          this.ensureSelectionMarker(coordinates, mode)
          this.setAreaData(areaFeatureCollection([{
            ...coordinates,
            exact: false,
            radius_meters: this.radius()
          }]))
          return
        }

        this.setAreaData(emptyFeatureCollection())
        this.ensureSelectionMarker(coordinates, mode)
      }

      this.syncMode = () => {
        const mode = this.mode()
        this.el.dataset.locationMode = mode

        if (mode === "hidden") {
          this.clearCoordinates()
          this.setStatus(this.el.dataset.hiddenLabel)
        } else {
          this.renderSelection()
          this.setSelectionStatus()
          window.requestAnimationFrame(() => this.map?.resize())
        }
      }

      this.onChange = event => {
        if (event.target.matches("[data-location-mode-input]")) {
          this.syncMode()
          return
        }

        if (event.target.matches("[data-location-radius-input]")) {
          this.renderSelection()
          this.setSelectionStatus()
          return
        }

        if (event.target.matches("[data-coordinate-input]")) {
          this.renderSelection()

          if (this.coordinates()) {
            this.focusSelection()
            this.setSelectionStatus()
          }
        }
      }

      this.onClick = event => {
        const button = event.target.closest("[data-use-current-location]")
        if (!button) return

        if (!navigator.geolocation) {
          this.setStatus(this.el.dataset.locationUnavailableLabel)
          return
        }

        button.disabled = true
        navigator.geolocation.getCurrentPosition(
          position => {
            const raw = {
              latitude: position.coords.latitude,
              longitude: position.coords.longitude
            }
            const selected = this.mode() === "approximate_public"
              ? privacySafeAreaCenter(raw.latitude, raw.longitude, this.radius())
              : raw

            this.setCoordinates(selected, {center: true})
            this.setStatus(
              this.mode() === "approximate_public"
                ? this.el.dataset.areaSelectedLabel
                : this.el.dataset.pointSelectedLabel
            )
            button.disabled = false
          },
          () => {
            this.setStatus(this.el.dataset.locationDeniedLabel)
            button.disabled = false
          },
          {enableHighAccuracy: true, timeout: 10000}
        )
      }

      this.cacheElements()
      this.el.addEventListener("change", this.onChange)
      this.el.addEventListener("click", this.onClick)

      if (!this.mapElement || !supportsMapCanvas()) {
        if (this.mapElement) {
          this.mapUnavailable = true
          this.renderMapUnavailable()
        }
        this.syncMode()
        return
      }

      const initialCoordinates = this.coordinates()
      this.map = new maplibregl.Map({
        container: this.mapElement,
        style: defaultStyle,
        center: initialCoordinates
          ? [initialCoordinates.longitude, initialCoordinates.latitude]
          : [30.5234, 50.4501],
        zoom: initialCoordinates ? 13 : 5,
        attributionControl: true,
        dragRotate: false,
        pitchWithRotate: false
      })
      this.map.touchZoomRotate.disableRotation()
      this.map.addControl(new maplibregl.NavigationControl({showCompass: false}), "top-left")

      this.map.on("load", () => {
        this.mapLoaded = true
        this.mapElement.dataset.mapReady = "true"
        this.ensureAreaLayers()
        this.renderSelection()
      })

      this.map.on("click", event => {
        if (this.mode() === "hidden") return

        this.setCoordinates(
          {latitude: event.lngLat.lat, longitude: event.lngLat.lng},
          {center: true}
        )
        this.setStatus(
          this.mode() === "approximate_public"
            ? this.el.dataset.areaSelectedLabel
            : this.el.dataset.pointSelectedLabel
        )
      })

      this.syncMode()
    },
    updated() {
      this.cacheElements()
      if (this.mapUnavailable) this.renderMapUnavailable()
      this.syncMode()
    },
    destroyed() {
      this.el.removeEventListener("change", this.onChange)
      this.el.removeEventListener("click", this.onClick)
      this.removeMarker()
      this.map?.remove()
    }
  },

  LocationPicker: {
    mounted() {
      this.el.addEventListener("click", () => {
        const latitudeInput = document.querySelector(this.el.dataset.latitudeTarget)
        const longitudeInput = document.querySelector(this.el.dataset.longitudeTarget)

        if (!latitudeInput || !longitudeInput || !navigator.geolocation) {
          this.el.textContent = "Location is unavailable"
          this.el.classList.add("btn-error")
          return
        }

        navigator.geolocation.getCurrentPosition(
          position => {
            latitudeInput.value = position.coords.latitude
            longitudeInput.value = position.coords.longitude
            latitudeInput.dispatchEvent(new Event("input", {bubbles: true}))
            longitudeInput.dispatchEvent(new Event("input", {bubbles: true}))
            this.el.textContent = "Location added"
            this.el.classList.add("btn-success")
          },
          () => {
            this.el.textContent = "Location permission denied"
            this.el.classList.add("btn-error")
          },
          {enableHighAccuracy: true, timeout: 10000}
        )
      })
    }
  },

  LiveTracking: {
    mounted() {
      this.destroying = false
      this.lastLocationSentAt = 0
      this.pendingLocation = null
      this.locationTimer = undefined

      this.sendLocation = payload => {
        this.lastLocationSentAt = Date.now()
        this.pendingLocation = null
        this.pushEvent("location-update", payload)
      }

      this.queueLocation = payload => {
        const elapsed = Date.now() - this.lastLocationSentAt

        if (this.lastLocationSentAt === 0 || elapsed >= trackingMinTimeMs) {
          if (this.locationTimer !== undefined) {
            window.clearTimeout(this.locationTimer)
            this.locationTimer = undefined
          }

          this.sendLocation(payload)
          return
        }

        this.pendingLocation = payload

        if (this.locationTimer === undefined) {
          this.locationTimer = window.setTimeout(() => {
            this.locationTimer = undefined

            if (!this.destroying && this.pendingLocation) {
              this.sendLocation(this.pendingLocation)
            }
          }, trackingMinTimeMs - elapsed)
        }
      }

      if (typeof window.WhoNeedHelpAndroid?.postMessage === "function") {
        this.nativeError = () => {
          this.pushEvent("location-error", {})
          this.pushEvent("stop-tracking", {})
        }
        window.addEventListener("wnh:native-tracking-error", this.nativeError)
        return
      }

      this.watchId = navigator.geolocation.watchPosition(
        position => this.queueLocation({
          latitude: position.coords.latitude,
          longitude: position.coords.longitude,
          accuracy_meters: position.coords.accuracy
        }),
        () => {
          if (!this.destroying) this.pushEvent("location-error", {})
        },
        {enableHighAccuracy: true, maximumAge: 5000, timeout: 15000}
      )
    },
    destroyed() {
      this.destroying = true
      this.pendingLocation = null

      if (this.locationTimer !== undefined) {
        window.clearTimeout(this.locationTimer)
        this.locationTimer = undefined
      }

      if (this.nativeError) {
        window.removeEventListener("wnh:native-tracking-error", this.nativeError)
      }
      if (this.watchId !== undefined) navigator.geolocation.clearWatch(this.watchId)
    }
  }
}

function supportsMapCanvas() {
  const canvas = document.createElement("canvas")
  const attributes = {
    alpha: true,
    depth: true,
    stencil: true,
    premultipliedAlpha: true
  }

  try {
    const context =
      canvas.getContext("webgl2", attributes) ||
      canvas.getContext("webgl", attributes)

    if (!context) return false

    return true
  } catch (_error) {
    return false
  }
}