build: bump version to 4.4.7-ba7opf.16 (509)

feat(map): add TianDiTu switching and AutoTLE sources

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/LoTWRepository.kt

@@ -252,17 +252,40 @@ class LoTWRepository : ILoTWRepository {
         var country: String? = null
         var cqz: Int? = null
         var state: String? = null
-        var myGrid: String? = null
+        // Own-station (台址) fields: MY_GRIDSQUARE + MY_VUCC_GRIDS give the
+        // full grid set of the station location; the remaining MY_* fields
+        // together identify the station location (one callsign can own
+        // several locations, and one location can span several grids).
+        var myGrids = mutableSetOf<String>()
+        var myCallsign: String? = null
+        var myDxcc: String? = null
+        var myState: String? = null
+        var myCq: String? = null
+        var myItu: String? = null
+        var myIota: String? = null
+        var myCountry: String? = null
         val gridsInRecord = mutableListOf<String>()
 
         fun emitRecord() {
             if (propMode != "SAT" || gridsInRecord.isEmpty()) return
             val epochMs = adifTimestampToEpoch(qsoDate, timeOn)
+            val stationKey = buildString {
+                append(myCallsign ?: "")
+                append('|').append(myDxcc ?: "")
+                append('|').append(myState ?: "")
+                append('|').append(myCq ?: "")
+                append('|').append(myItu ?: "")
+                append('|').append(myIota ?: "")
+                append('|').append(myCountry ?: "")
+            }.ifBlank { null }
             val qso = com.rtbishop.look4sat.core.domain.model.GridQso(
                 call = call, epochMs = epochMs, satName = satName,
                 mode = mode, bandUp = bandUp, bandDown = bandDown,
                 dxcc = dxcc, country = country, cqz = cqz, state = state,
-                myGrid = myGrid
+                myGrid = myGrids.firstOrNull(),
+                myGrids = myGrids,
+                myCallsign = myCallsign,
+                stationKey = stationKey
             )
             for (grid in gridsInRecord) {
                 result.getOrPut(grid) { mutableListOf() }.add(qso)
@@ -273,7 +296,9 @@ class LoTWRepository : ILoTWRepository {
             propMode = null; call = ""; qsoDate = ""; timeOn = ""
             satName = ""; mode = ""; bandUp = ""; bandDown = ""
             dxcc = null; country = null; cqz = null; state = null
-            myGrid = null
+            myGrids = mutableSetOf()
+            myCallsign = null; myDxcc = null; myState = null
+            myCq = null; myItu = null; myIota = null; myCountry = null
             gridsInRecord.clear()
         }
 
@@ -311,10 +336,40 @@ class LoTWRepository : ILoTWRepository {
                 line.startsWith("<MY_GRIDSQUARE:") -> {
                     // Own-station grid (must not be confused with GRIDSQUARE —
                     // the opposite station's grid). Recorded per QSO so awards
-                    // can be counted per operated grid.
+                    // can be counted per operated grid. A station location may
+                    // also carry MY_VUCC_GRIDS (below) for multi-grid roaming.
                     val value = adifValue(line)
-                    if (value.length >= 4) myGrid = value.take(4).uppercase()
+                    if (value.length >= 4) myGrids.add(value.take(4).uppercase())
                 }
+                line.startsWith("<MY_VUCC_GRIDS:") -> {
+                    // Own-station VUCC grids: a comma-separated list LoTW emits
+                    // when one station location spans several grid squares
+                    // (e.g. "OM60,OM50" with MY_GRIDSQUARE absent). Without
+                    // this field the extra grids of a multi-grid 台址 silently
+                    // vanished from both the blue stripes and the per-台址 VUCC
+                    // count. Same split/truncate as VUCC_GRIDS below.
+                    adifValue(line).split(',').forEach { grid ->
+                        val field = grid.trim().uppercase()
+                        if (field.length >= 4) myGrids.add(field.take(4))
+                    }
+                }
+                // Remaining MY_* fields identify the station location (台址):
+                // grouped together they form the stationKey used by the map's
+                // operated-grid selector. One callsign can own several 台址.
+                line.startsWith("<STATION_CALLSIGN:") ->
+                    myCallsign = adifValue(line).trim().uppercase().ifBlank { null }
+                line.startsWith("<MY_DXCC:") ->
+                    myDxcc = adifValue(line).trim().ifBlank { null }
+                line.startsWith("<MY_STATE:") ->
+                    myState = adifValue(line).trim().ifBlank { null }?.let { normalizeState(it) }
+                line.startsWith("<MY_CQ_ZONE:") ->
+                    myCq = adifValue(line).trim().ifBlank { null }
+                line.startsWith("<MY_ITU_ZONE:") ->
+                    myItu = adifValue(line).trim().ifBlank { null }
+                line.startsWith("<MY_IOTA:") ->
+                    myIota = adifValue(line).trim().uppercase().ifBlank { null }
+                line.startsWith("<MY_COUNTRY:") ->
+                    myCountry = adifValue(line).trim().ifBlank { null }
                 line.startsWith("<GRIDSQUARE:") || line.startsWith("<VUCC_GRIDS:") -> {
                     // VUCC_GRIDS holds a comma-separated list of grids
                     // ("EN52en,EN53fa"), up to four for contacts spanning
@@ -420,23 +475,30 @@ class LoTWRepository : ILoTWRepository {
         // would silently drop every own grid on real reports; buffer the record
         // and decide at <EOR> instead.
         var propMode: String? = null
-        var myGrid: String? = null
+        var myGrids = mutableSetOf<String>()
         for (raw in body.lineSequence()) {
             val line = raw.trim()
             when {
                 line.equals("<EOR>", ignoreCase = true) -> {
-                    if (propMode == "SAT" && myGrid != null) grids.add(myGrid)
+                    if (propMode == "SAT" && myGrids.isNotEmpty()) grids.addAll(myGrids)
                     propMode = null
-                    myGrid = null
+                    myGrids = mutableSetOf()
                 }
                 line.startsWith("<PROP_MODE:") -> {
                     propMode = adifValue(line).uppercase()
                 }
                 line.startsWith("<MY_GRIDSQUARE:") -> {
-                    // MY_GRIDSQUARE must not be mistaken for GRIDSQUARE (the
-                    // opposite station's grid) — only own-station grids count.
                     val value = adifValue(line)
-                    if (value.length >= 4) myGrid = value.take(4)
+                    if (value.length >= 4) myGrids.add(value.take(4).uppercase())
+                }
+                line.startsWith("<MY_VUCC_GRIDS:") -> {
+                    // Multi-grid 台址: each field of MY_VUCC_GRIDS is a grid the
+                    // station location covered; without this the extra grids
+                    // never reached the blue stripes.
+                    adifValue(line).split(',').forEach { grid ->
+                        val field = grid.trim().uppercase()
+                        if (field.length >= 4) myGrids.add(field.take(4))
+                    }
                 }
             }
         }

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/SettingsRepo.kt

@@ -25,6 +25,7 @@ import androidx.core.location.LocationListenerCompat
 import androidx.core.location.LocationManagerCompat
 import com.rtbishop.look4sat.core.domain.model.DataSourcesSettings
 import com.rtbishop.look4sat.core.domain.model.DatabaseState
+import com.rtbishop.look4sat.core.domain.model.MapSource
 import com.rtbishop.look4sat.core.domain.model.OtherSettings
 import com.rtbishop.look4sat.core.domain.model.PassesSettings
 import com.rtbishop.look4sat.core.domain.model.RCSettings
@@ -98,6 +99,8 @@ class SettingsRepo(
     private val keySstvMode = "sstvMode"
     private val keyLowElevation = "lowElevation"
     private val keyHighElevation = "highElevation"
+    private val keyMapSource = "mapSource"
+    private val keyTiandituKey = "tiandituKey"
     private val keyUseCustomTle = "useCustomTle"
     private val keyUseCustomTransceivers = "useCustomTransceivers"
     private val keyTleUrl = "tleUrl"
@@ -107,6 +110,7 @@ class SettingsRepo(
     private val keySatelliteEnabled = "satelliteEnabled"
     private val keyTransceiversEnabled = "transceiversEnabled"
     private val keySatnogsTleSourceMigration = "satnogsTleSourceMigration"
+    private val keyAutoTleSourceMigration = "autoTleSourceMigration"
     private val separatorComma = ","
     private val separatorUrl = "\n"
     private val legacyCelestrakSatnogsUrl =
@@ -210,7 +214,20 @@ class SettingsRepo(
                         cqz = o.optInt("cq", 0).takeIf { it > 0 },
                         state = o.optString("st").ifBlank { null },
                         // Own-grid field: absent in pre-myGrid data -> null.
-                        myGrid = o.optString("mg").ifBlank { null }
+                        myGrid = o.optString("mg").ifBlank { null },
+                        // Multi-grid 台址 fields (v4.4.7-ba7opf.16+): "mgs" is
+                        // the full grid set (MY_GRIDSQUARE + MY_VUCC_GRIDS);
+                        // pre-multi-grid data has only "mg" and falls back to a
+                        // single-element set so every consumer sees myGrids.
+                        myGrids = o.optJSONArray("mgs")?.let { arr ->
+                            (0 until arr.length()).mapNotNull { i ->
+                                arr.optString(i).takeIf { it.isNotBlank() }
+                            }.toSet()
+                        }?.takeIf { it.isNotEmpty() }
+                            ?: o.optString("mg").ifBlank { null }?.let { setOf(it) }
+                            ?: emptySet(),
+                        myCallsign = o.optString("mc").ifBlank { null },
+                        stationKey = o.optString("sk").ifBlank { null }
                     )
                 }
                 if (list.isNotEmpty()) result[grid] = list
@@ -239,6 +256,9 @@ class SettingsRepo(
                         .put("cq", q.cqz ?: 0)
                         .put("st", q.state ?: "")
                         .put("mg", q.myGrid ?: "")
+                        .put("mgs", org.json.JSONArray(q.myGrids.sorted()))
+                        .put("mc", q.myCallsign ?: "")
+                        .put("sk", q.stationKey ?: "")
                 )
             }
             root.put(grid, array)
@@ -597,7 +617,12 @@ class SettingsRepo(
 
     override fun updateOtherSettings(transform: (OtherSettings) -> OtherSettings) {
         _otherSettings.update { current ->
-            val new = transform(current)
+            val new = transform(current).let {
+                it.copy(
+                    mapSource = MapSource.normalize(it.mapSource),
+                    tiandituKey = it.tiandituKey.trim()
+                )
+            }
             preferences.edit {
                 putBoolean(keyStateOfAutoUpdate, new.stateOfAutoUpdate)
                 putBoolean(keyStateOfAutoLotwSync, new.stateOfAutoLotwSync)
@@ -614,6 +639,8 @@ class SettingsRepo(
                 putString(keySstvMode, new.sstvMode)
                 putLong(keyLowElevation, new.lowElevation.toRawBits())
                 putLong(keyHighElevation, new.highElevation.toRawBits())
+                putString(keyMapSource, new.mapSource)
+                putString(keyTiandituKey, new.tiandituKey)
             }
             new
         }
@@ -634,7 +661,9 @@ class SettingsRepo(
         shouldSeeWhatsNew = preferences.getBoolean(keyShouldSeeWhatsNew, true),
         sstvMode = preferences.getString(keySstvMode, null) ?: "Auto",
         lowElevation = Double.fromBits(preferences.getLong(keyLowElevation, 15.0.toRawBits())),
-        highElevation = Double.fromBits(preferences.getLong(keyHighElevation, 45.0.toRawBits()))
+        highElevation = Double.fromBits(preferences.getLong(keyHighElevation, 45.0.toRawBits())),
+        mapSource = MapSource.normalize(preferences.getString(keyMapSource, null).orEmpty()),
+        tiandituKey = preferences.getString(keyTiandituKey, null).orEmpty().trim()
     )
     //endregion
 
@@ -656,6 +685,7 @@ class SettingsRepo(
             putString(keySatelliteEnabled, normalized.satelliteEnabled.joinToString(separatorComma))
             putString(keyTransceiversEnabled, normalized.transceiversEnabled.joinToString(separatorComma))
             putBoolean(keySatnogsTleSourceMigration, true)
+            putBoolean(keyAutoTleSourceMigration, true)
         }
         _dataSourcesSettings.value = normalized
     }
@@ -666,7 +696,7 @@ class SettingsRepo(
             defaultUrls = Sources.satelliteDataUrls.values.filter { it.isNotBlank() },
             legacyEnabledKey = keyUseCustomTle,
             legacyUrlKey = keyTleUrl
-        ).migrateSatnogsTleSource(),
+        ).migrateSatnogsTleSource().migrateAutoTleSources(),
         transceiversUrls = getDataSourceUrls(
             key = keyTransceiversUrls,
             defaultUrls = Sources.transceiversDataUrls.values.filter { it.isNotBlank() },
@@ -727,6 +757,28 @@ class SettingsRepo(
         return migrated
     }
 
+    private fun List<String>.migrateAutoTleSources(): List<String> {
+        if (preferences.getBoolean(keyAutoTleSourceMigration, false)) return this
+        val autoTleUrls = listOfNotNull(
+            Sources.satelliteDataUrls["BI4PYM AutoTLE (GitHub)"],
+            Sources.satelliteDataUrls["BI4PYM AutoTLE (Mirror)"]
+        ).filter { it.isNotBlank() }
+        val missingUrls = autoTleUrls.filterNot { containsSourceUrl(it) }
+        if (missingUrls.isEmpty()) {
+            preferences.edit { putBoolean(keyAutoTleSourceMigration, true) }
+            return this
+        }
+
+        val migrated = this + missingUrls
+        val enabled = alignFlags(migrated, readEnabledFlags(keySatelliteEnabled))
+        preferences.edit {
+            putString(keySatelliteUrls, migrated.joinToString(separatorUrl))
+            putString(keySatelliteEnabled, enabled.joinToString(separatorComma))
+            putBoolean(keyAutoTleSourceMigration, true)
+        }
+        return migrated
+    }
+
     private fun List<String>.containsSourceUrl(url: String): Boolean = any { isSameSourceUrl(it, url) }
 
     private fun isSameSourceUrl(first: String, second: String): Boolean =

core/data/src/test/java/com/rtbishop/look4sat/core/data/repository/LoTWRepositoryTest.kt

@@ -169,6 +169,53 @@ class LoTWRepositoryTest {
         assertTrue(repo.parseConfirmedGridQsos(report(qso1, ground))!!.values.all { it.all { q -> q.myGrid == "OL62" } })
     }
 
+    @Test
+    fun parseQsosCapturesMyVuccGridsMultiGridStation() {
+        // A station location (台址) can span several grids: LoTW emits
+        // <MY_VUCC_GRIDS> (comma-separated) with MY_GRIDSQUARE absent. Both
+        // grids must land in myGrids, and myGrid (back-compat) = the first.
+        val qso = "<CALL:5>A50QO\n<QSO_DATE:8>20260820\n<TIME_ON:4>1130\n" +
+            "<PROP_MODE:3>SAT\n<SAT_NAME:5>RS-44\n<MODE:2>CW\n" +
+            "<MY_VUCC_GRIDS:11>OM60,OM50\n<GRIDSQUARE:4>NL47\n<EOR>\n"
+        val result = repo.parseConfirmedGridQsos(report(qso))!!
+        val parsed = result["NL47"]!!.first()
+        assertEquals(setOf("OM60", "OM50"), parsed.myGrids)
+        assertEquals("OM60", parsed.myGrid)
+        // 6-char fields are truncated to 4 like every other grid path.
+        val six = "<PROP_MODE:3>SAT\n<SAT_NAME:5>RS-44\n" +
+            "<MY_VUCC_GRIDS:17>OM60IL70,OM50MA20\n<GRIDSQUARE:4>OK48\n<EOR>\n"
+        assertEquals(setOf("OM60", "OM50"), repo.parseConfirmedGridQsos(report(six))!!["OK48"]!!.first().myGrids)
+    }
+
+    @Test
+    fun parseQsosBuildsStationKeyFromMyFields() {
+        // 台址 identity = the MY_* station snapshot (callsign + dxcc + state +
+        // CQ/ITU + IOTA + country). A record with the full snapshot yields the
+        // stable key the operated-grid selector groups by.
+        val qso = "<CALL:5>A50QO\n<QSO_DATE:8>20260820\n<TIME_ON:4>1130\n" +
+            "<PROP_MODE:3>SAT\n<SAT_NAME:5>RS-44\n" +
+            "<STATION_CALLSIGN:6>BH6RJD\n<MY_DXCC:3>318\n<MY_STATE:11>JS // Jiangsu\n" +
+            "<MY_CQ_ZONE:2>24\n<MY_ITU_ZONE:2>44\n<MY_COUNTRY:5>CHINA\n" +
+            "<GRIDSQUARE:4>NL47\n<EOR>\n"
+        val parsed = repo.parseConfirmedGridQsos(report(qso))!!["NL47"]!!.first()
+        assertEquals("BH6RJD", parsed.myCallsign)
+        assertEquals("BH6RJD|318|JS|24|44||CHINA", parsed.stationKey)
+    }
+
+    @Test
+    fun parseQsosStationKeyDistinguishesLocationsUnderSameCallsign() {
+        // One callsign can own several 台址 (e.g. BH6RJD with a Hubei location
+        // and a Zhejiang location); different MY_STATE -> different stationKey.
+        val hb = "<CALL:5>A50QO\n<QSO_DATE:8>20260820\n<TIME_ON:4>1130\n" +
+            "<PROP_MODE:3>SAT\n<SAT_NAME:5>RS-44\n" +
+            "<STATION_CALLSIGN:6>BH6RJD\n<MY_STATE:11>HB // Hubei\n<GRIDSQUARE:4>NL47\n<EOR>\n"
+        val zj = "<CALL:5>BG7ZFK\n<QSO_DATE:8>20260819\n<TIME_ON:4>1130\n" +
+            "<PROP_MODE:3>SAT\n<SAT_NAME:5>SO-50\n" +
+            "<STATION_CALLSIGN:6>BH6RJD\n<MY_STATE:11>ZJ // Zhejiang\n<GRIDSQUARE:4>OK48\n<EOR>\n"
+        val result = repo.parseConfirmedGridQsos(report(hb, zj))!!
+        assertTrue(result["NL47"]!!.first().stationKey != result["OK48"]!!.first().stationKey)
+    }
+
     // endregion
 
     // region parseRoamedGrids (MY_GRIDSQUARE = grids the account operated from)
@@ -224,6 +271,30 @@ class LoTWRepositoryTest {
         assertNull(repo.parseRoamedGrids("<HTML>Username/password incorrect</HTML>"))
     }
 
+    @Test
+    fun parseRoamedGridsCollectsMyVuccGrids() {
+        // Multi-grid 台址: MY_VUCC_GRIDS carries the extra grids (MY_GRIDSQUARE
+        // may be absent); every field must reach the roamed set for the stripes.
+        val qso = "<PROP_MODE:3>SAT\n<SAT_NAME:5>RS-44\n" +
+            "<MY_VUCC_GRIDS:11>OM60,OM50\n<GRIDSQUARE:4>NL47\n<EOR>\n"
+        assertEquals(setOf("OM60", "OM50"), repo.parseRoamedGrids(report(qso)))
+        // Combined with MY_GRIDSQUARE the union is kept.
+        val both = "<PROP_MODE:3>SAT\n<SAT_NAME:5>RS-44\n" +
+            "<MY_GRIDSQUARE:4>OL62\n<MY_VUCC_GRIDS:11>OM60,OM50\n<GRIDSQUARE:4>NL47\n<EOR>\n"
+        assertEquals(setOf("OL62", "OM60", "OM50"), repo.parseRoamedGrids(report(both)))
+    }
+
+    @Test
+    fun parseRoamedGridsUppercasesLowercaseMyGrid() {
+        // LoTW emits the <eor> tag lowercase, so field CASE is not guaranteed:
+        // a lowercase MY_GRIDSQUARE must still match the overlay's uppercase
+        // labels (regression: take(4) without .uppercase() silently dropped
+        // stripes for lowercase grids).
+        val qso = "<PROP_MODE:3>SAT\n<SAT_NAME:5>IO-86\n" +
+            "<MY_GRIDSQUARE:4>ol62\n<GRIDSQUARE:4>PM95\n<EOR>\n"
+        assertEquals(setOf("OL62"), repo.parseRoamedGrids(report(qso)))
+    }
+
     // endregion
 
     // region failure classification (fetchReportBody -> LoTWResult mapping)

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/GridQso.kt

@@ -49,8 +49,27 @@ data class GridQso(
     val country: String? = null,
     val cqz: Int? = null,
     val state: String? = null,
-    /** 4-char grid the station itself operated from (ADIF MY_GRIDSQUARE). */
-    val myGrid: String? = null
+    /** 4-char grid the station itself operated from (ADIF MY_GRIDSQUARE).
+     *  Kept as the first entry of [myGrids] for backward compatibility with
+     *  consumers that predate multi-grid station locations. */
+    val myGrid: String? = null,
+    /** Every 4-char grid the station operated from for this QSO — ADIF
+     *  <MY_GRIDSQUARE> plus every field of <MY_VUCC_GRIDS> (a comma-separated
+     *  list LoTW emits when one station location roams across several grid
+     *  squares; MY_GRIDSQUARE may be absent on those records). A station
+     *  location (台址) can legitimately span multiple grids, and the map's
+     *  stripes and the operated-grid selector must show all of them. */
+    val myGrids: Set<String> = emptySet(),
+    /** Callsign of the station location this QSO was logged under (ADIF
+     *  <STATION_CALLSIGN>; e.g. "BH6RJD", "BH6RJD/P"). NOT the 台址 identity
+     *  on its own — one callsign can have several station locations. */
+    val myCallsign: String? = null,
+    /** Stable key of the station location (台址) this QSO was logged under,
+     *  derived from the MY_* station fields (STATION_CALLSIGN + MY_DXCC +
+     *  MY_STATE + MY_CQ_ZONE + MY_ITU_ZONE + MY_IOTA + MY_COUNTRY), so the
+     *  operated-grid selector can group QSOs per 台址 and show each 台址 with
+     *  its full grid set. Null for data synced before this field existed. */
+    val stationKey: String? = null
 ) {
     /** Short uplink/downlink band label ("U/V", "V/A"), or "" when unknown. */
     val bandLabel: String

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/Settings.kt

@@ -75,9 +75,23 @@ data class OtherSettings(
      *  ephemeris auto-update; only effective after at least one manual sync). */
     val stateOfAutoLotwSync: Boolean = true,
     /** 指南针手动航向偏置(度, -180..180): 雷达方位 = 传感器方位 + 磁偏角 + 该偏置. */
-    val compassOffsetDegrees: Float = 0f
+    val compassOffsetDegrees: Float = 0f,
+    val mapSource: String = MapSource.OSM,
+    val tiandituKey: String = ""
 )
 
+object MapSource {
+    const val OSM = "osm"
+    const val TIANDITU_VECTOR = "tianditu_vector"
+    const val TIANDITU_IMAGE = "tianditu_image"
+    private const val LEGACY_TIANDITU = "tianditu"
+
+    fun normalize(source: String): String = when (source) {
+        OSM, TIANDITU_VECTOR, TIANDITU_IMAGE -> source
+        LEGACY_TIANDITU -> TIANDITU_VECTOR
+        else -> OSM
+    }
+}
 data class DataSourcesSettings(
     val satelliteUrls: List<String>,
     val transceiversUrls: List<String>,

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/source/Sources.kt

@@ -21,6 +21,8 @@ object Sources {
     val satelliteDataUrls = mapOf(
         "LAPAN-A2" to "https://www.kaggle.com/api/v1/datasets/download/muazamnugroho/lapan-a2-satellite-two-line-element-tle-dataset/LAPAN-A2_TLE_latest.txt",
         "R4UAB" to "https://r4uab.ru/satonline.txt",
+        "BI4PYM AutoTLE (GitHub)" to "https://raw.githubusercontent.com/BI4PYM/AutoTLE/refs/heads/master/AutoTLE.txt",
+        "BI4PYM AutoTLE (Mirror)" to "https://autotle.bi4pym.cn/AutoTLE.txt",
         "All" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=active&FORMAT=csv",
         "SatNOGS" to "https://db.satnogs.org/api/tle/?format=3le",
         "Amateur" to "https://celestrak.org/NORAD/elements/gp.php?GROUP=amateur&FORMAT=csv",

core/presentation/src/main/res/values-tr/strings.xml

@@ -88,7 +88,7 @@
     <!-- Map screen -->
     <string name="map_prev">Önceki</string>
     <string name="map_next">Sonraki</string>
-    <string name="map_copyright" translatable="false">© OpenStreetMap contributors</string>
+    <string name="map_copyright_osm" translatable="false">© OpenStreetMap contributors</string>
     <string name="map_azimuth">Azimut: %.1f°</string>
     <string name="map_elevation">Yükseklik açısı: %.1f°</string>
     <string name="map_altitude">İrtifa: %.0f km</string>
@@ -209,7 +209,8 @@
         \n• Alexandru Csete (Gpredict)
         \n• Dr T.S. Kelso (Celestrak)
         \n• Libre Space Foundation (SatNOGS)
-        \n• BG7NTA BG5JSU (CW decoding feature)</string>
+        \n• BG7NTA BG5JSU (CW decoding feature)
+        \n• BH2VSQ BG5JSU (TianDiTu rendering support)</string>
     <string name="prefs_outro_license">Bu uygulama herhangi bir garanti sunmaz</string>
 
 </resources>

core/presentation/src/main/res/values-zh/strings.xml

@@ -247,6 +247,15 @@
     <string name="rc_enable_switch">启用 CAT 控制</string>
 
     <string name="prefs_other_title">其他设置</string>
+    <string name="prefs_map_title">地图设置</string>
+    <string name="prefs_map_configure">配置地图</string>
+    <string name="prefs_map_source_title">地图来源</string>
+    <string name="prefs_map_source_osm">离线 OSM 地图</string>
+    <string name="prefs_map_source_tianditu_vector">天地图（矢量）</string>
+    <string name="prefs_map_source_tianditu_image">天地图（影像）</string>
+    <string name="prefs_map_tianditu_key">天地图访问密钥</string>
+    <string name="prefs_map_tianditu_key_help">使用天地图前，需先在天地图开发者控制台申请服务端应用 Key。</string>
+    <string name="prefs_map_tianditu_key_required">选择天地图需要填写访问密钥；保存密钥前将继续使用离线 OSM 地图。</string>
     <string name="prefs_other_switch_utc">以 UTC 时间显示</string>
     <string name="prefs_other_switch_update">启用卫星数据自动更新</string>
     <string name="prefs_other_switch_lotw_sync">自动同步 LoTW 已确认网格</string>
@@ -282,7 +291,8 @@
         \n• Dr T.S. Kelso (Celestrak)
         \n• Libre Space Foundation (SatNOGS)
         \n• xdsopl 和 Robot36 贡献者!
-        \n• BG7NTA BG5JSU（CW解码功能）</string>
+        \n• BG7NTA BG5JSU（CW解码功能）
+        \n• BH2VSQ BG5JSU（天地图渲染支持）</string>
     <string name="prefs_outro_license">该应用程序不提供任何保修.</string>
 
     <!-- 匹配页 Mutual match page -->

core/presentation/src/main/res/values/strings.xml

@@ -128,7 +128,8 @@
     <!-- Map screen -->
     <string name="map_prev">Prev</string>
     <string name="map_next">Next</string>
-    <string name="map_copyright" translatable="false">© OpenStreetMap contributors</string>
+    <string name="map_copyright_osm" translatable="false">© OpenStreetMap contributors</string>
+    <string name="map_copyright_tianditu" translatable="false">© Tianditu</string>
     <string name="map_grid_mode">Grid mode</string>
     <string name="map_satellite_mode">Satellite mode</string>
     <string name="map_first_call_mode">First call</string>
@@ -276,6 +277,15 @@
     <string name="prefs_net_perm_error">Check your network permission</string>
 
     <string name="prefs_other_title">Other settings</string>
+    <string name="prefs_map_title">Map settings</string>
+    <string name="prefs_map_configure">Configure map</string>
+    <string name="prefs_map_source_title">Map source</string>
+    <string name="prefs_map_source_osm">Offline OSM</string>
+    <string name="prefs_map_source_tianditu_vector">TianDiTu vector</string>
+    <string name="prefs_map_source_tianditu_image">TianDiTu imagery</string>
+    <string name="prefs_map_tianditu_key">TianDiTu access key</string>
+    <string name="prefs_map_tianditu_key_help">Request a server-side application key from the TianDiTu developer console before using TianDiTu maps.</string>
+    <string name="prefs_map_tianditu_key_required">A TianDiTu key is required. Offline OSM remains active until it is entered.</string>
     <string name="prefs_other_switch_utc">Show pass time in UTC</string>
     <string name="prefs_other_switch_update">Enable automatic data update</string>
     <string name="prefs_other_switch_lotw_sync">Auto-sync LoTW confirmed grids</string>
@@ -312,6 +322,7 @@
         \n* Libre Space Foundation (SatNOGS)
         \n* xdsopl and Robot36 contributors!
         \n* BG7NTA BG5JSU (CW decoding feature)
+        \n* BH2VSQ BG5JSU (TianDiTu rendering support)
     </string>
     <string name="prefs_outro_license">The app comes with no warranty</string>
 

feature/map/src/main/java/com/rtbishop/look4sat/feature/map/MapScreen.kt

@@ -85,6 +85,7 @@ import androidx.lifecycle.viewmodel.compose.viewModel
 import com.rtbishop.look4sat.core.domain.model.AwardCalculator
 import com.rtbishop.look4sat.core.domain.model.AwardProgress
 import com.rtbishop.look4sat.core.domain.model.AwardType
+import com.rtbishop.look4sat.core.domain.model.MapSource
 import com.rtbishop.look4sat.core.domain.predict.GeoPos
 import com.rtbishop.look4sat.core.domain.predict.OrbitalObject
 import com.rtbishop.look4sat.core.domain.predict.OrbitalPos
@@ -96,31 +97,40 @@ import com.rtbishop.look4sat.core.presentation.TimerRow
 import com.rtbishop.look4sat.core.presentation.TopBar
 import com.rtbishop.look4sat.core.presentation.isVerticalLayout
 import com.rtbishop.look4sat.core.presentation.layoutPadding
+import org.osmdroid.tileprovider.MapTileProviderBasic
+import org.osmdroid.tileprovider.tilesource.OnlineTileSourceBase
 import org.osmdroid.tileprovider.tilesource.XYTileSource
 import org.osmdroid.events.DelayedMapListener
 import org.osmdroid.events.MapListener
 import org.osmdroid.events.ScrollEvent
 import org.osmdroid.events.ZoomEvent
 import org.osmdroid.util.GeoPoint
+import org.osmdroid.util.MapTileIndex
 import org.osmdroid.views.CustomZoomButtonsController
 import org.osmdroid.views.MapView
 import org.osmdroid.views.overlay.FolderOverlay
 import org.osmdroid.views.overlay.Marker
 import org.osmdroid.views.overlay.Polyline
+import org.osmdroid.views.overlay.TilesOverlay
+import java.net.URLEncoder
 
 // Overlay indices
-private const val OVERLAY_GRID = 0
-private const val OVERLAY_STATION = 1
-private const val OVERLAY_TRACK = 2
-private const val OVERLAY_FOOTPRINT = 3
-private const val OVERLAY_POSITIONS = 4
-private const val OVERLAY_TERMINATOR = 5
-private const val OVERLAY_SUN = 6
-private const val OVERLAY_MOON = 7
-private const val OVERLAY_COUNT = 8
+private const val OVERLAY_TDT_LABELS = 0
+private const val OVERLAY_GRID = 1
+private const val OVERLAY_STATION = 2
+private const val OVERLAY_TRACK = 3
+private const val OVERLAY_FOOTPRINT = 4
+private const val OVERLAY_POSITIONS = 5
+private const val OVERLAY_TERMINATOR = 6
+private const val OVERLAY_SUN = 7
+private const val OVERLAY_MOON = 8
+private const val OVERLAY_COUNT = 9
 
 private val minLat = MapView.getTileSystem().minLatitude
 private val maxLat = MapView.getTileSystem().maxLatitude
+private val offlineTileSource = XYTileSource("tiles", 0, 6, 256, ".webp", emptyArray<String>())
+private const val OFFLINE_MAX_ZOOM = 7.0
+private const val TIANDITU_MAX_ZOOM = 18.0
 private val trackPaint = Paint(Paint.ANTI_ALIAS_FLAG).apply {
     strokeWidth = 3f
     style = Paint.Style.STROKE
@@ -209,6 +219,8 @@ private fun MapScreen(
     val rotateMod = Modifier.rotate(180f)
     val timeString = uiState.mapData?.aosTime ?: "00:00:00"
     val isTimeAos = uiState.mapData?.isTimeAos ?: true
+    val usesTianditu = tiandituLayers(uiState.mapSource) != null && uiState.tiandituKey.isNotBlank()
+    val copyrightResId = if (usesTianditu) R.string.map_copyright_tianditu else R.string.map_copyright_osm
 
     // Tapped worked grid -> centered QSO dialog. Local UI state: the map is the
     // only consumer and it resets when leaving the page.
@@ -216,19 +228,6 @@ private fun MapScreen(
     // Selected award filter. Lives in an Activity-scoped ViewModel so it
     // survives page switches; defaults to VUCC only once per process (cold start).
     var selectedAward by mapFilterViewModel.selectedAward
-    // Six-award progress derived from the confirmed QSO store; recomputed when
-    // the store changes (LoTW/Wavelog sync).
-    // Per operated-grid VUCC breakdown: myGrid -> set of worked grids worked from it.
-    val vuccByMyGrid: Map<String, Set<String>> = remember(uiState.workedGridQsos) {
-        val m = mutableMapOf<String, MutableSet<String>>()
-        for ((grid, qsos) in uiState.workedGridQsos) {
-            for (q in qsos) {
-                val mg = q.myGrid ?: continue
-                m.getOrPut(mg) { mutableSetOf() }.add(grid)
-            }
-        }
-        m
-    }
     // First callsign worked in each grid (earliest QSO by time), used by the
     // "首通呼号" label mode — derived from the same QSO store as the worked fills.
     val firstCallsByGrid: Map<String, String> = remember(uiState.workedGridQsos) {
@@ -236,26 +235,47 @@ private fun MapScreen(
             qsos.minByOrNull { it.epochMs }?.let { grid to it.call }
         }.toMap()
     }
-    // Selected operated grid for VUCC counting; defaults to the grid with the
-    // most worked grids. Null when the store carries no per-QSO myGrid data
-    // (requires a LoTW resync) — then VUCC falls back to the global count.
-    var selectedMyGrid by remember(vuccByMyGrid) {
-        mutableStateOf(vuccByMyGrid.maxByOrNull { it.value.size }?.key)
+    // 台址名单: QSOs grouped by the 台址's GRID SET. A station location (台址)
+    // can span several grids (MY_GRIDSQUARE + MY_VUCC_GRIDS), and QSOs whose
+    // location covers the same grid set belong to the same 台址; groups with an
+    // identical grid set merge (they are VUCC-equivalent — the MY_* snapshot
+    // can differ between records of the same physical 台址 when LoTW omits
+    // optional fields). Data synced before multi-grid support falls back to
+    // one group per grid, preserving the old selector exactly.
+    val stationGroups: List<StationGroup> = remember(uiState.workedGridQsos) {
+        val byGridSet = LinkedHashMap<String, Pair<Set<String>, MutableSet<String>>>()
+        for ((grid, qsos) in uiState.workedGridQsos) {
+            for (q in qsos) {
+                val gs = q.myGrids.ifEmpty { q.myGrid?.let { setOf(it) }.orEmpty() }
+                if (gs.isEmpty()) continue
+                val key = gs.sorted().joinToString(",")
+                byGridSet.getOrPut(key) { gs to mutableSetOf() }.second.add(grid)
+            }
+        }
+        byGridSet.map { (key, v) -> StationGroup(id = key, grids = v.first, worked = v.second) }
+            .sortedByDescending { it.workedCount }
     }
-    val awardProgress: List<AwardProgress> = remember(uiState.workedGridQsos, vuccByMyGrid, selectedMyGrid) {
-        val vuccGrids = selectedMyGrid?.let { vuccByMyGrid[it].orEmpty() }
+    // Selected 台址 for VUCC counting; defaults to the group with the most
+    // worked grids. Null = "All" (every 台址 combined). Empty when the store
+    // carries no per-QSO myGrid data (requires a LoTW resync) — the selector
+    // is hidden then and VUCC falls back to the global count.
+    var selectedStationId by remember(stationGroups) {
+        mutableStateOf(stationGroups.maxByOrNull { it.workedCount }?.id)
+    }
+    val awardProgress: List<AwardProgress> = remember(uiState.workedGridQsos, stationGroups, selectedStationId) {
         val base = AwardCalculator.calculate(uiState.workedGridQsos)
-        if (vuccGrids == null) base
+        val worked = stationGroups.firstOrNull { it.id == selectedStationId }?.worked
+        if (worked == null) base
         else base.map { p ->
-            if (p.type == AwardType.VUCC) p.copy(workedKeys = vuccGrids, count = vuccGrids.size) else p
+            if (p.type == AwardType.VUCC) p.copy(workedKeys = worked, count = worked.size) else p
         }
     }
-    // Worked grids drawn on the map: filtered by the selected operated grid
-    // (null = all operated grids). Drives both the green fills and the tap
-    // listener below, so switching the selector changes which cells are green.
-    val workedGrids = remember(uiState.workedGrids, vuccByMyGrid, selectedMyGrid) {
-        if (selectedMyGrid == null) uiState.workedGrids
-        else vuccByMyGrid[selectedMyGrid] ?: emptySet()
+    // Worked grids drawn on the map: filtered by the selected 台址 (null = all).
+    // Drives both the green fills and the tap listener below, so switching the
+    // selector changes which cells are green.
+    val workedGrids = remember(uiState.workedGrids, stationGroups, selectedStationId) {
+        if (selectedStationId == null) uiState.workedGrids
+        else stationGroups.firstOrNull { it.id == selectedStationId }?.worked ?: emptySet()
     }
     val isGridMode = uiState.isGridMode
     // True when this composition restored a saved viewport. Only grid mode
@@ -300,6 +320,9 @@ private fun MapScreen(
         val firstPos = uiState.track?.firstOrNull()?.firstOrNull() ?: return@LaunchedEffect
         mapView.controller.animateTo(GeoPoint(firstPos.latitude, firstPos.longitude))
     }
+    LaunchedEffect(uiState.mapSource, uiState.tiandituKey) {
+        configureTileSources(mapView, uiState.mapSource, uiState.tiandituKey)
+    }
     Column(modifier = Modifier.layoutPadding(), verticalArrangement = Arrangement.spacedBy(6.dp)) {
         val isVertical = isVerticalLayout()
         if (isGridMode) {
@@ -382,17 +405,18 @@ private fun MapScreen(
                 }
                 uiState.mapData?.let { mapData ->
                     if (!uiState.isGridMode) {
-                        if (isVertical) MapDataCard(mapData) else MapDataCards(mapData)
+                        if (isVertical) MapDataCard(mapData, copyrightResId)
+                        else MapDataCards(mapData, copyrightResId)
                     }
                 }
-                // Top-left: operated-grid selector for VUCC counting (grid mode only).
+                // Top-left: 台址 selector for VUCC counting (grid mode only).
                 // Shown whenever per-grid QSO data exists; "All" (null) is available.
-                if (uiState.isGridMode && selectedAward == AwardType.VUCC && vuccByMyGrid.isNotEmpty()) {
+                if (uiState.isGridMode && selectedAward == AwardType.VUCC && stationGroups.isNotEmpty()) {
                     VuccGridSelector(
-                        options = vuccByMyGrid,
+                        stations = stationGroups,
                         allCount = uiState.workedGrids.size,
-                        selected = selectedMyGrid,
-                        onSelect = { selectedMyGrid = it },
+                        selected = selectedStationId,
+                        onSelect = { selectedStationId = it },
                         modifier = Modifier
                             .align(Alignment.TopStart)
                             .padding(8.dp)
@@ -761,11 +785,11 @@ private fun formatTime(epochMs: Long, isUtc: Boolean): String {
 
 // region Map data composables
 @Composable
-private fun MapDataCard(data: MapData) {
+private fun MapDataCard(data: MapData, copyrightResId: Int) {
     val textColor = MaterialTheme.colorScheme.primary
     val cardColors = CardDefaults.cardColors(containerColor = MaterialTheme.colorScheme.surfaceContainerLowest)
     Column(horizontalAlignment = Alignment.CenterHorizontally) {
-        Text(text = stringResource(R.string.map_copyright), fontSize = 14.sp)
+        Text(text = stringResource(copyrightResId), fontSize = 14.sp)
         Card(colors = cardColors) {
             Column(modifier = Modifier.padding(horizontal = 8.dp, vertical = 4.dp)) {
                 MapDataRow(
@@ -803,7 +827,7 @@ private fun MapDataRow(
 }
 
 @Composable
-private fun MapDataCards(data: MapData) {
+private fun MapDataCards(data: MapData, copyrightResId: Int) {
     val cardColors = CardDefaults.cardColors(containerColor = MaterialTheme.colorScheme.surfaceContainerLowest)
     val paddingMod = Modifier
         .padding(horizontal = 8.dp, vertical = 4.dp)
@@ -830,7 +854,7 @@ private fun MapDataCards(data: MapData) {
             }
         }
         Text(
-            text = stringResource(R.string.map_copyright),
+            text = stringResource(copyrightResId),
             fontSize = 14.sp,
             modifier = Modifier.align(Alignment.BottomCenter)
         )
@@ -881,22 +905,42 @@ private fun AwardChipsRow(
 }
 
 /**
- * Compact pill toggle for switching between satellite view and grid mode,
+ * One 台址 shown by the operated-grid selector. A 台址 is a station location
+ * and can span SEVERAL grids (MY_GRIDSQUARE + MY_VUCC_GRIDS); groups are keyed
+ * by the 台址's full grid set, so a multi-grid 台址 is one entry listing all
+ * its grids. Data synced before multi-grid support falls back to one group
+ * per grid.
+ */
+private data class StationGroup(
+    /** Grid-set key (sorted 4-char grids joined by ","). */
+    val id: String,
+    /** Full grid set of this 台址 (1..n 4-char grids). */
+    val grids: Set<String>,
+    /** Distinct worked grids worked under this 台址 (any of its grids). */
+    val worked: Set<String>
+) {
+    val workedCount: Int get() = worked.size
+    /** Selector label: the grids themselves — "OL62" for a single-grid 台址,
+     *  "OM60,PM01" for a multi-grid one (matches how 台址 are described). */
+    val label: String get() = grids.sorted().joinToString(",")
+}
+
+/** Compact pill toggle for switching between satellite view and grid mode,
  * floated over the map's top-right corner. The label reflects the active
  * mode ("Grid mode" when ON, "Satellite mode" when OFF). Semi-transparent
- * background keeps the map readable underneath.
- */
+ * background keeps the map readable underneath. */
 @Composable
 private fun VuccGridSelector(
-    options: Map<String, Set<String>>,
+    stations: List<StationGroup>,
     allCount: Int,
     selected: String?,
     onSelect: (String?) -> Unit,
     modifier: Modifier = Modifier
 ) {
     var expanded by remember { mutableStateOf(false) }
-    // Most-worked grid first; selection is made on tap. "All" sits last.
-    val sorted = remember(options) { options.entries.sortedByDescending { it.value.size } }
+    // Most-worked 台址 first; selection is made on tap. "All" sits last.
+    val sorted = remember(stations) { stations.sortedByDescending { it.workedCount } }
+    val selectedLabel = stations.firstOrNull { it.id == selected }?.label
     Surface(
         color = ComposeColor.Black.copy(alpha = 0.45f),
         shape = RoundedCornerShape(8.dp),
@@ -914,8 +958,8 @@ private fun VuccGridSelector(
                     .padding(start = 10.dp, end = 6.dp, top = 4.dp, bottom = 4.dp)
             ) {
                 Text(
-                    text = if (selected == null) "All ($allCount)"
-                    else "$selected (${options[selected]?.size ?: 0})",
+                    text = if (selectedLabel == null) "All ($allCount)"
+                    else "$selectedLabel (${stations.firstOrNull { it.id == selected }?.workedCount ?: 0})",
                     color = ComposeColor.White,
                     fontSize = 12.sp,
                     fontFamily = androidx.compose.ui.text.font.FontFamily.Monospace
@@ -929,20 +973,20 @@ private fun VuccGridSelector(
             }
             if (expanded) {
                 androidx.compose.material3.HorizontalDivider(color = ComposeColor.White.copy(alpha = 0.2f))
-                sorted.forEach { (grid, grids) ->
+                sorted.forEach { station ->
                     Row(
                         verticalAlignment = Alignment.CenterVertically,
                         modifier = Modifier
                             .fillMaxWidth()
                             .clickable {
-                                onSelect(grid)
+                                onSelect(station.id)
                                 expanded = false
                             }
                             .padding(horizontal = 10.dp, vertical = 3.dp)
                     ) {
                         Text(
-                            text = "$grid (${grids.size})",
-                            color = if (grid == selected) MaterialTheme.colorScheme.primary else ComposeColor.White,
+                            text = "${station.label} (${station.workedCount})",
+                            color = if (station.id == selected) MaterialTheme.colorScheme.primary else ComposeColor.White,
                             fontSize = 12.sp,
                             fontFamily = androidx.compose.ui.text.font.FontFamily.Monospace
                         )
@@ -1045,6 +1089,100 @@ private fun FirstCallToggle(
 
 // endregion
 
+// region Tile sources
+private var configuredTileMapView: MapView? = null
+private var configuredTileSource: String? = null
+
+private fun configureTileSources(mapView: MapView, mapSource: String, tiandituKey: String) {
+    val key = tiandituKey.trim()
+    val layers = tiandituLayers(mapSource)
+    val sourceKey = if (layers == null || key.isBlank()) MapSource.OSM else "${layers.base}:$key"
+    if (configuredTileMapView === mapView && configuredTileSource == sourceKey) return
+
+    configuredTileMapView = mapView
+    configuredTileSource = sourceKey
+    (mapView.overlays.getOrNull(OVERLAY_TDT_LABELS) as? TilesOverlay)?.onDetach(mapView)
+
+    if (layers == null || key.isBlank()) {
+        mapView.setUseDataConnection(false)
+        mapView.setTileSource(offlineTileSource)
+        mapView.maxZoomLevel = OFFLINE_MAX_ZOOM
+        mapView.overlayManager.tilesOverlay.applyTileOverlayDefaults(createColorFilter())
+        mapView.overlays[OVERLAY_TDT_LABELS] = FolderOverlay()
+        requestTileRefresh(mapView)
+        return
+    }
+
+    mapView.setUseDataConnection(true)
+    mapView.setTileSource(TiandituTileSource(layer = layers.base, key = key))
+    mapView.maxZoomLevel = TIANDITU_MAX_ZOOM
+    mapView.overlayManager.tilesOverlay.applyTileOverlayDefaults(null)
+    mapView.overlays[OVERLAY_TDT_LABELS] = TilesOverlay(
+        MapTileProviderBasic(mapView.context, TiandituTileSource(layer = layers.label, key = key)),
+        mapView.context
+    ).apply {
+        applyTileOverlayDefaults(null)
+        setUseDataConnection(true)
+    }
+    requestTileRefresh(mapView)
+}
+
+private data class TiandituLayers(val base: String, val label: String)
+
+private fun tiandituLayers(mapSource: String): TiandituLayers? = when (MapSource.normalize(mapSource)) {
+    MapSource.TIANDITU_VECTOR -> TiandituLayers(base = "vec", label = "cva")
+    MapSource.TIANDITU_IMAGE -> TiandituLayers(base = "img", label = "cia")
+    else -> null
+}
+
+private fun TilesOverlay.applyTileOverlayDefaults(colorFilter: ColorMatrixColorFilter?) {
+    setColorFilter(colorFilter)
+    setLoadingBackgroundColor(Color.TRANSPARENT)
+    setLoadingLineColor(Color.TRANSPARENT)
+}
+
+private fun requestTileRefresh(mapView: MapView) {
+    mapView.post {
+        mapView.requestLayout()
+        mapView.invalidate()
+    }
+}
+
+private fun buildTiandituWmtsUrl(
+    baseUrl: String,
+    layer: String,
+    zoom: Int,
+    row: Int,
+    col: Int,
+    encodedKey: String
+): String = "$baseUrl?SERVICE=WMTS&REQUEST=GetTile&VERSION=1.0.0&LAYER=$layer" +
+    "&STYLE=default&TILEMATRIXSET=w&FORMAT=tiles&TILEMATRIX=$zoom&TILEROW=$row&TILECOL=$col&tk=$encodedKey"
+
+private class TiandituTileSource(
+    private val layer: String,
+    key: String
+) : OnlineTileSourceBase(
+    "tianditu-wmts-https-$layer",
+    1,
+    TIANDITU_MAX_ZOOM.toInt(),
+    256,
+    ".png",
+    Array(8) { index -> "https://t$index.tianditu.gov.cn/${layer}_w/wmts" },
+    "Tianditu"
+) {
+    private val encodedKey = URLEncoder.encode(key, Charsets.UTF_8.name())
+
+    override fun getTileURLString(pMapTileIndex: Long): String = buildTiandituWmtsUrl(
+        baseUrl = getBaseUrl(),
+        layer = layer,
+        zoom = MapTileIndex.getZoom(pMapTileIndex),
+        row = MapTileIndex.getY(pMapTileIndex),
+        col = MapTileIndex.getX(pMapTileIndex),
+        encodedKey = encodedKey
+    )
+}
+// endregion
+
 // region Map overlay helpers
 
 /**
@@ -1463,7 +1601,6 @@ private fun rememberMapViewWithLifecycle(
     mapFilterViewModel: MapFilterViewModel,
     restoreViewport: Boolean
 ): MapView {
-    val tileSource = XYTileSource("tiles", 0, 6, 256, ".webp", emptyArray<String>())
     val context = LocalContext.current
     val isVertical = isVerticalLayout()
     val mapView = remember {
@@ -1475,9 +1612,9 @@ private fun rememberMapViewWithLifecycle(
             // draws a full-height artifact line whenever its X range crosses
             // the screen at low zoom. The map must never repeat vertically.
             setVerticalMapRepetitionEnabled(false)
-            setTileSource(tileSource)
+            setTileSource(offlineTileSource)
             minZoomLevel = getMinZoom(resources.displayMetrics.heightPixels, isVertical)
-            maxZoomLevel = 7.0
+            maxZoomLevel = OFFLINE_MAX_ZOOM
             // Restore the viewport the user left on the previous visit, but only
             // in grid mode: satellite mode intentionally keeps its original
             // behavior (default center, then follows the selected satellite).
@@ -1522,6 +1659,8 @@ private fun clearMapCaches() {
     lastPositions = null
     lastAction = null
     lastMapView = null
+    configuredTileMapView = null
+    configuredTileSource = null
 }
 
 @Composable

feature/map/src/main/java/com/rtbishop/look4sat/feature/map/MapState.kt

@@ -21,11 +21,14 @@ import com.rtbishop.look4sat.core.domain.predict.GeoPos
 import com.rtbishop.look4sat.core.domain.predict.OrbitalObject
 import com.rtbishop.look4sat.core.domain.predict.OrbitalPass
 import com.rtbishop.look4sat.core.domain.predict.OrbitalPos
+import com.rtbishop.look4sat.core.domain.model.MapSource
 
 data class MapState(
     val mapData: MapData? = null,
     val isLightUi: Boolean = false,
     val isUtc: Boolean = false,
+    val mapSource: String = MapSource.OSM,
+    val tiandituKey: String = "",
     val isGridMode: Boolean = false,
     /** Grid mode: label worked (green) cells with the first callsign worked in
      *  that grid instead of the grid code; non-worked cells get no label. */

feature/map/src/main/java/com/rtbishop/look4sat/feature/map/MapViewModel.kt

@@ -63,6 +63,8 @@ class MapViewModel(
         MapState(
             isLightUi = settingsRepo.otherSettings.value.stateOfLightTheme,
             isUtc = settingsRepo.otherSettings.value.stateOfUtc,
+            mapSource = settingsRepo.otherSettings.value.mapSource,
+            tiandituKey = settingsRepo.otherSettings.value.tiandituKey,
             orbitalPass = defaultPass
         )
     )
@@ -82,6 +84,8 @@ class MapViewModel(
                 _uiState.update {
                     it.copy(
                         isUtc = settings.stateOfUtc,
+                        mapSource = settings.mapSource,
+                        tiandituKey = settings.tiandituKey,
                         isGridMode = settings.stateOfMapGrid,
                         showFirstCallLabels = settings.stateOfMapFirstCall
                     )

feature/settings/src/main/java/com/rtbishop/look4sat/feature/settings/MapSettingsDialog.kt

@@ -0,0 +1,119 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.feature.settings
+
+import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.FlowRow
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.material3.FilterChip
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.saveable.rememberSaveable
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.input.ImeAction
+import androidx.compose.ui.text.input.KeyboardType
+import androidx.compose.ui.text.input.PasswordVisualTransformation
+import androidx.compose.ui.unit.dp
+import com.rtbishop.look4sat.core.domain.model.MapSource
+import com.rtbishop.look4sat.core.domain.model.OtherSettings
+import com.rtbishop.look4sat.core.presentation.R
+import com.rtbishop.look4sat.core.presentation.SharedDialog
+
+@Composable
+fun MapSettingsDialog(
+    settings: OtherSettings,
+    onDismiss: () -> Unit,
+    onSave: (mapSource: String, tiandituKey: String) -> Unit
+) {
+    var selectedSource by rememberSaveable {
+        mutableStateOf(MapSource.normalize(settings.mapSource))
+    }
+    var tiandituKey by rememberSaveable { mutableStateOf(settings.tiandituKey) }
+
+    SharedDialog(
+        title = stringResource(R.string.prefs_map_title),
+        onDismissRequest = onDismiss,
+        onCancel = onDismiss,
+        onAccept = { onSave(selectedSource, tiandituKey) }
+    ) { padding ->
+        Column(
+            verticalArrangement = Arrangement.spacedBy(8.dp),
+            modifier = Modifier.padding(horizontal = padding)
+        ) {
+            Text(
+                text = stringResource(R.string.prefs_map_source_title),
+                color = MaterialTheme.colorScheme.primary
+            )
+            FlowRow(horizontalArrangement = Arrangement.spacedBy(6.dp)) {
+                MapSourceChip(
+                    selected = selectedSource == MapSource.OSM,
+                    label = stringResource(R.string.prefs_map_source_osm),
+                    onClick = { selectedSource = MapSource.OSM }
+                )
+                MapSourceChip(
+                    selected = selectedSource == MapSource.TIANDITU_VECTOR,
+                    label = stringResource(R.string.prefs_map_source_tianditu_vector),
+                    onClick = { selectedSource = MapSource.TIANDITU_VECTOR }
+                )
+                MapSourceChip(
+                    selected = selectedSource == MapSource.TIANDITU_IMAGE,
+                    label = stringResource(R.string.prefs_map_source_tianditu_image),
+                    onClick = { selectedSource = MapSource.TIANDITU_IMAGE }
+                )
+            }
+            Text(
+                text = stringResource(R.string.prefs_map_tianditu_key_help),
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant
+            )
+            OutlinedTextField(
+                value = tiandituKey,
+                onValueChange = { tiandituKey = it },
+                label = { Text(stringResource(R.string.prefs_map_tianditu_key)) },
+                visualTransformation = PasswordVisualTransformation(),
+                keyboardOptions = KeyboardOptions(
+                    keyboardType = KeyboardType.Password,
+                    imeAction = ImeAction.Done
+                ),
+                singleLine = true,
+                modifier = Modifier.fillMaxWidth()
+            )
+            if (selectedSource != MapSource.OSM && tiandituKey.isBlank()) {
+                Text(
+                    text = stringResource(R.string.prefs_map_tianditu_key_required),
+                    style = MaterialTheme.typography.bodySmall,
+                    color = MaterialTheme.colorScheme.error
+                )
+            }
+        }
+    }
+}
+
+@Composable
+private fun MapSourceChip(selected: Boolean, label: String, onClick: () -> Unit) {
+    FilterChip(selected = selected, onClick = onClick, label = { Text(label) })
+}

feature/settings/src/main/java/com/rtbishop/look4sat/feature/settings/SettingsScreen.kt

@@ -99,6 +99,7 @@ fun SettingsDestination() {
 @Composable
 private fun SettingsScreen(uiState: SettingsState, onAction: (SettingsAction) -> Unit) {
     var showUpdateChecker by rememberSaveable { mutableStateOf(false) }
+    var showMapSettings by rememberSaveable { mutableStateOf(false) }
     if (showUpdateChecker) {
         UpdateCheckerScreen(
             currentVersion = uiState.appVersionName,
@@ -129,6 +130,17 @@ private fun SettingsScreen(uiState: SettingsState, onAction: (SettingsAction) ->
         }
     )
 
+    if (showMapSettings) {
+        MapSettingsDialog(
+            settings = uiState.otherSettings,
+            onDismiss = { showMapSettings = false },
+            onSave = { mapSource, tiandituKey ->
+                onAction(SettingsAction.UpdateMapSettings(mapSource, tiandituKey))
+                showMapSettings = false
+            }
+        )
+    }
+
     // Dialogs
     if (dialogs.position) {
         PositionDialog(
@@ -368,6 +380,7 @@ private fun SettingsScreen(uiState: SettingsState, onAction: (SettingsAction) ->
                     onAction = onAction
                 )
             }
+            item { MapSettingsCard(onClick = { showMapSettings = true }) }
             item { CardCredits() }
             item(span = { GridItemSpan(maxLineSpan) }) {
                 CardButton(
@@ -558,6 +571,24 @@ private fun OtherCardPreview() = MainTheme {
     OtherCard(settings = values, onCompassCalibration = {}, onAction = {})
 }
 
+@Composable
+private fun MapSettingsCard(onClick: () -> Unit) {
+    ElevatedCard(modifier = Modifier.fillMaxWidth()) {
+        Column(modifier = Modifier.padding(horizontal = 8.dp, vertical = 6.dp)) {
+            Text(
+                text = stringResource(R.string.prefs_map_title),
+                color = MaterialTheme.colorScheme.primary
+            )
+            Spacer(modifier = Modifier.height(6.dp))
+            CardButton(
+                onClick = onClick,
+                text = stringResource(R.string.prefs_map_configure),
+                modifier = Modifier.fillMaxWidth()
+            )
+        }
+    }
+}
+
 @Composable
 private fun OtherCard(
     settings: OtherSettings,

feature/settings/src/main/java/com/rtbishop/look4sat/feature/settings/SettingsState.kt

@@ -108,6 +108,7 @@ sealed interface SettingsAction {
     data class SetCompassOffset(val degrees: Float) : SettingsAction
     data class ToggleLightTheme(val value: Boolean) : SettingsAction
     data class ToggleNightMode(val value: Boolean) : SettingsAction
+    data class UpdateMapSettings(val mapSource: String, val tiandituKey: String) : SettingsAction
 
     // Remote control
     data class UpdateRC(val settings: RCSettings) : SettingsAction

feature/settings/src/main/java/com/rtbishop/look4sat/feature/settings/SettingsViewModel.kt

@@ -186,6 +186,9 @@ class SettingsViewModel(
             }
             is SettingsAction.ToggleLightTheme -> settingsRepo.updateOtherSettings { it.copy(stateOfLightTheme = action.value) }
             is SettingsAction.ToggleNightMode -> settingsRepo.updateOtherSettings { it.copy(stateOfNightMode = action.value) }
+            is SettingsAction.UpdateMapSettings -> settingsRepo.updateOtherSettings {
+                it.copy(mapSource = action.mapSource, tiandituKey = action.tiandituKey)
+            }
             // Remote control & data sources
             is SettingsAction.UpdateRC -> settingsRepo.updateRCSettings(action.settings)
             is SettingsAction.UpdateRadioControl -> settingsRepo.updateRadioControlSettings(action.settings)

gradle/libs.versions.toml

@@ -1,8 +1,8 @@
 [versions]
 #noinspection UnusedVersionCatalogEntry
-appVersionCode = "507"
+appVersionCode = "509"
 #noinspection UnusedVersionCatalogEntry
-appVersionName = "4.4.7-ba7opf.15.10"
+appVersionName = "4.4.7-ba7opf.16"
 #noinspection UnusedVersionCatalogEntry
 compileSdk = "37"
 #noinspection UnusedVersionCatalogEntry