# 03: Downloads füllen den Cache

**What to build:** Einstellungen replace the Cache section and start collapsed. Inside, Hessen herunterladen stays those words. It is red while any Kachel of Hessen is missing from the Cache, and disabled once every one of them is stored. Starting it fetches only the missing Kacheln, at every prepared scale, the current scale first. A second press while that fill is running adds nothing. Closing the app stops the fill. Opening the app does not continue it. Pressing again fetches what is still missing. While the app stays open, losing the network pauses the fill and regaining it continues it. Looking around still fetches only the current view at the current scale. Ganzen Cache löschen asks first, then removes every Kachel and does not start a fetch. There is no Hessen entfernen.

**Blocked by:** None (can start immediately).

**Status:** ready-for-agent

The session contract in the spec is the seam. This ticket owns `startHessen`, `hessen` and `visit` on the snapshot, the shared queue, pause on offline, and stop on close. `deleteCache` drops Kacheln and the visit fills, does not itself start a fetch, and leaves Ziele and the checkbox. There is no `removeGebiet` and no heruntergeladen mark. The screen copy for a running fill is `Kacheln: ${arrived} von ${total}`.

- [x] Einstellungen replace the Cache section and start collapsed. Hessen herunterladen and Ganzen Cache löschen are inside it.
- [x] Hessen herunterladen keeps that label. It is red while any Kachel of Hessen is missing, and disabled, and shown as disabled, once every Kachel of Hessen is in the Cache.
- [x] Starting Hessen fetches only missing Kacheln of Hessen, at every prepared scale from 1.25 m per pixel up to the 36 km span. Kacheln of the current scale arrive first.
- [x] A second press of Hessen herunterladen, while that fill is running, adds nothing further.
- [x] While the fill runs, Einstellungen show how many of the Kacheln requested in this visit have arrived. Kacheln already in the Cache stay usable.
- [x] Losing the network while the app stays open pauses the fill. Regaining the network continues it. No fetch runs while the device is offline.
- [x] Leaving the app stops the fill. Opening the app does not continue it, and shows no leftover progress. Pressing Hessen herunterladen again fetches only the Kacheln still missing.
- [x] Looking around, while online and the app is open, fetches only the missing Kacheln of the current view at the current scale.
- [x] The app does not mark a Gebiet heruntergeladen, and it offers no Hessen entfernen.
- [x] Ganzen Cache löschen asks "Den ganzen Cache löschen?" first. Declining leaves the Cache unchanged. Accepting removes every Kachel, does not start a fetch, and makes Hessen herunterladen red and active again.

## Comments

The person starts Hessen from Einstellungen. Finished Kacheln stay in the Cache. The fill does not resume on its own, and the only way to drop Kacheln is to delete the whole Cache after confirming.