> ## Documentation Index
> Fetch the complete documentation index at: https://docs.appliedaifoundation.org/llms.txt
> Use this file to discover all available pages before exploring further.

# History viewer overview

> What the viewer is, what it can do, and what it can't.

The Metaweave History Viewer is a **single-file HTML app** (\~71 KB) that browses every report a vessel has ever submitted. It's read-only, offline, and lives next to the form in the same shared-drive folder.

<Frame caption="History viewer — Voyage Reports tab.">
  <img src="https://mintcdn.com/metaweaveconsultant/Yh8TWLsifrpzxzbC/images/history/viewer-voyage-tab.png?fit=max&auto=format&n=Yh8TWLsifrpzxzbC&q=85&s=715cd5fba674cabb079f287b24bd1662" alt="History viewer voyage tab" width="2832" height="952" data-path="images/history/viewer-voyage-tab.png" />
</Frame>

## What it does

* Reads a `history.json` file from disk via the **File System Access API**
* Lists every submission across **four tabs**: Voyage Reports, Statement of Facts, Bunker Reports, Month-End ROB
* Filters by date range and free-text search; the Voyage tab adds NOON / ARRIVAL / DEPARTURE pill toggles
* Clicks a row → opens a detail modal with all 90+ fields organised into seven zones, plus child tables for events, port activities, fuel breakdowns, BDN data
* Exports the filtered set to **CSV** or **Excel** (multi-sheet SpreadsheetML)
* Exports a single report from the detail modal to Excel or Print

## What it doesn't do

* **No editing.** FSA permission is `mode: 'read'`. The viewer cannot modify `history.json`.
* **No deletion.** Same reason.
* **No PDF export.** Print uses the browser's print dialog; CSV and Excel are the only file outputs.
* **No vessel comparison.** It loads one `history.json` at a time. To compare vessels, switch the linked file via Re-link.
* **No map view.** No geographic visualisation.

## How it gets the data

The viewer never makes network requests. It reads the file the user selects via the **File System Access API**, a Chrome 86+ feature that bypasses CORS and avoids the `file://` restrictions that break a normal `fetch()` from a local HTML page.

The selected file's handle is persisted in **IndexedDB** so the viewer auto-loads the same file next time. The user can re-link a different file at any time.

See [Viewing past reports](/history/viewing) for the user flow and [Setting up history.json](/history/setup) for how the file gets created.

## Browser requirements

| Browser        | Status                                                                |
| -------------- | --------------------------------------------------------------------- |
| **Chrome 86+** | ✅ Supported                                                           |
| **Edge 86+**   | ✅ Supported                                                           |
| Firefox        | ❌ No File System Access API — viewer shows "Unsupported browser" gate |
| Safari         | ❌ No File System Access API — viewer shows "Unsupported browser" gate |

If a Master uses Firefox, the form *still works* (form Submit doesn't strictly require FSA), but the local archive and the viewer don't.

## The four tabs

<CardGroup cols={2}>
  <Card title="Voyage Reports">
    NOON / ARRIVAL / DEPARTURE submissions. Most-used tab.
    Columns: Submitted, Type, Report UTC, Vessel, Voyage, Location, Port, Lat/Lon, Events.
  </Card>

  <Card title="Statement of Facts">
    SOF submissions only.
    Columns: Submitted, Report UTC, Vessel, Voyage, Port, Activities (count).
  </Card>

  <Card title="Bunker Reports">
    Bunker lifts only.
    Columns: Submitted, Date, Vessel, Voyage, Port, BDN No, Quantity (MT).
  </Card>

  <Card title="Month-End ROB">
    Month-end bunker reconciliations only.
    Columns: Submitted, Month, Vessel, Voyage.
  </Card>
</CardGroup>

The viewer auto-routes each submission to the correct tab based on its `reportType` field — `NOON` / `ARRIVAL` / `DEPARTURE` go to Voyage, `SOF` to Statement of Facts, `BUNKER` to Bunker, `MONTH_END_BUNKER` to Month-End.

## Detail modal

Clicking any row opens a full-screen modal showing the entire submission in seven labeled zones:

| Zone                   | Examples                                                  |
| ---------------------- | --------------------------------------------------------- |
| Identity               | reportName, version, voyageNumber, vesselName, vesselCode |
| Position & Port        | lat/long, port, ETD, ice/STS/refuge flags                 |
| Vessel State           | vessel condition, drafts, DWT, displacement               |
| Distance & Main Engine | observed distance, slip, ME hours, RPM, KW                |
| Generators & Auxiliary | gen 1–4 hours/KWhrs, aux boiler, incinerator              |
| Lub Oil & Tanks        | stern tube lub, ROBs, bilge, sludge                       |
| Slops & Fresh Water    | slops, freshwater ROB / consumed / received               |

Below the zones, child tables render:

* **Event cards** (NOON / ARRIVAL / DEPARTURE) — at-sea and in-port events with per-fuel consumption breakdown
* **Port Activities** (SOF) — activity rows with dynamic columns
* **BDN Fuel / Biofuel** (Bunker) — `gsfueltypeandquantity` and `bdnbiofuel` arrays
* **Upcoming Ports** — destination + ETA

## See also

* [Viewing past reports](/history/viewing) — the click path from "open the file" to "export to Excel"
* [Setting up history.json](/history/setup) — what the file is, how it gets created and linked
* [Data format](/history/data-format) — the JSON schema each row follows