endorphin-tessera-gui/README.md

# Tessera

Tessera is a native desktop UI host embedding [Aster](vendor/aster/README.md).
Agents submit ordinary Endor scripts through a local namespace API. Aster parses,
compiles and executes them; `ui.page().render(root)` selects a Tessera UI tree. Tessera extracts a
native tree, lays it out and draws it using the existing software renderer.
The initial page is empty.

## Source and library integration

`vendor/aster` is an independent Git submodule pinned to a published Aster commit.
Cargo path dependencies directly use its `frontend`, `compiler` and `core`
(library name `endor_core`) packages, which bring in `objects`. The Aster workspace
and history remain independent. See [vendor](vendor/README.md) for initialization
and version updates, and [src](src/README.md) for the implementation map.

The runtime now uses Aster's Reader, Parser, AST, Compiler and VM. Tessera's former
experimental `namespace` / `export scene` / `render` parser has been removed.
Host UI integration lives in Tessera; Aster needs no Tessera-specific changes.
Lyra CLI and Hestia Server are independent hosts and are not application dependencies.

## Native build and start

Use Rust 1.91 or newer. Initialize the source submodule following the dedicated
codex-bot SSH identity instructions in [vendor](vendor/README.md), then build:

```bash
git submodule update --init --recursive
cargo build --release --locked
./target/release/tessera
```

Cargo compiles the required Aster libraries together with Tessera. No separate
Aster build, service or deployment is required. Local builds download dependencies
from official crates.io by default. A temporary dependency mirror may be used
when the official source is unavailable, without changing global configuration.
Docker and automated tests
are not used locally. The command above produces a native executable. To create a
Finder-launchable development app on macOS, run:

```bash
sh scripts/build-macos-app.sh
```

Open `target/release/Tessera.app`. See [packaging](scripts/README.md); this local
bundle does not include distribution signing, notarization or an installer.

The API listens only on `127.0.0.1:4737`. Start integrations with its live guide:

```bash
curl http://127.0.0.1:4737/agent
```

## Submit Endor

The active namespace starts as `app.main`:

```text
GET    /v1/namespaces/app.main/code
PUT    /v1/namespaces/app.main/code
DELETE /v1/namespaces/app.main/code
```

Submit the [complete example](examples/page.endor):

```bash
curl --request PUT --header 'Content-Type: text/plain; charset=utf-8' \
  --data-binary @examples/page.endor \
  http://127.0.0.1:4737/v1/namespaces/app.main/code
```

A minimal program is:

```endor
let heading = ui.text("Hello Endor", 2, "#242422")
let rectangle = ui.rect(240, 80, 12, "#DCE8FF")
let myui = ui.page()
myui.render(ui.column(24, 12, heading, rectangle))
```

The namespace comes from the request path. `ui` is a host global declared to
Aster's compiler and injected into the candidate VM. Top-level variables share
that VM's globals within this source submission. No `main` wrapper is generated.
Complete top-level inputs are separated by newlines; multiline calls and function
bodies are grouped before being handed to Aster's existing Interactive parser and
compiler. Expression continuations such as a member read on the following line
remain in the same input. Aster still owns every token, syntax rule, AST and
bytecode operation; the host only batches inputs and restores original AST offsets.

The older [main-returning-View example](examples/main.endor) and the richer
[function example](examples/hello.endor) remain supported. A source consisting
entirely of function declarations uses Aster's Module entry and calls zero-argument
`main`. Mixed function declarations, bindings and expression statements use
Interactive inputs in source order. Type annotations remain syntactic in Aster;
Tessera checks actual UI values. The sample files are client-side material; the
API itself stores source by namespace.

## UI host API

All arguments are positional. Defaults below describe omitted trailing arguments,
not Endor keyword argument syntax.

| Member | Arguments and defaults |
| --- | --- |
| `ui.text` | String, integer size (default 1, range 1..8), color (default `#242422`) |
| `ui.rect` | Width, height, radius (default 0), color (default `#DCE8FF`) |
| `ui.column` | Padding, gap, followed by zero or more UI children |
| `ui.row` | Padding, gap, followed by zero or more UI children |
| `ui.spacer` | Size |
| `ui.page` | No arguments; creates a page with a bound `render(root)` member |

Colors are `#RRGGBB` or `#RRGGBBAA`. Dimensions are finite numbers in 0..1000000.
A namespace has one displayed page. If a script creates several pages or renders
more than once, its final successful render selects the visible root. Rendering
does not publish partial execution: a later error rejects the entire submission.

Aster keeps its exact numeric representation; conversion occurs only at the UI
boundary. Text is shaped and antialiased with COSMIC Text and Swash, using
installed system fonts and per-glyph fallback (including Chinese when a CJK font
is installed). UI text uses a proportional sans-serif font; developer source uses
a monospace font. The existing size argument remains a 1..8 multiplier: size 1
is 14 logical pixels with a 20-pixel line height; size 2 is 28/40. Row/Column layout
uses measured text advances and multiline height. Device scale remains fractional,
and glyphs are rasterized at the actual display resolution rather than enlarged.
The application does not bundle proprietary OS fonts. Linux installations need
fonts such as DejaVu Sans/Mono and Noto CJK; the remote test image installs these.

## Candidate execution and publication

A dedicated worker performs source parsing, AST budget checks and compilation in
a fresh candidate VM. It executes each script input with shared globals (or module
initialization and zero-argument `main` for function-only source), checks the
selected UI root, extracts native data, builds and validates the frame, then
cleans up all VM roots. The window receives no VM handles. It relays out the owned
native tree during redraw and display scale changes without rerunning Endor.

Aster's scoped NativeContext allocates actual managed Block objects on demand.
Blocks own managed Cells and data objects; child, history and forwarding edges
are traced by the same VM collector. Native methods capture their owner through
declared heap edges. No fixed node/page pool or separate mutable Arc graph remains.
The desktop's tab registry holds open Pages. close releases that registry edge;
referenced Pages remain usable and unreferenced cycles are collected between inputs.
The bridge's diagnostic object index uses non-owning WeakObjectRef values.

Limits are 1 MiB source, 10000 visited AST nodes with a 64-level visitor depth,
4096 retained visual objects, 64 retained pages, 10000 expanded graph/layout visits
and 16 KiB per text. Every execution has a 128-frame limit. Script inputs each
receive an equal share of a total 1000000-instruction allowance; function-only
module initialization and main execution each retain a 1000000-instruction budget. Repeated children count again during layout, preventing a
small shared tree from expanding without bound. The build queue holds eight
pending requests.

GET reads the last successful source while the worker executes. PUT waits for its
result; a successful response includes submission and committed revision numbers.
Parsing, compilation, execution, argument or layout errors return 422 with
explanations and preserve the last successful document. Source diagnostics include
line, column and byte ranges; VM tracebacks currently identify function starts and
instruction offsets, not an exact source location for every instruction.

A newer accepted PUT invalidates older work. DELETE clears the document immediately
and invalidates both queued and executing candidates. Superseded requests return
409 and cannot republish their page. A full or unavailable queue returns 503;
rejected queue entries do not invalidate accepted work. Failed builds do not
increment the committed revision. A worker-caught panic discards the entire
candidate and returns 500, retaining the previous document.

This stage supports live mounted UI for both complete programs and Console inputs, with immutable window frames on the existing worker.
Native mouse/keyboard activation and code-driven callbacks share onClick/click. Managed Mount objects expose each occurrence, and property dependencies and measurement caches avoid recomputing clean visual subtrees. Arrangement still traverses occurrences.
Tab chrome/multiple windows, trait definitions and custom visual measurement/painting, window-size language inputs and process isolation are still being implemented. Worker threads,
source budgets and VM instruction limits are not a complete untrusted-code sandbox.

## Developer tools

Native visual protocols are under active implementation: Text/Rect/Row/Column,
container append/remove/replace/move, Page open/close/navigation, ui.present,
ui.state(value), ui.textOf(state, "value"), and button.onClick/click are available
in the persistent Console. Method bodies can call other methods without a trailing
return. Bound text tracks its source property; clean derived subtrees and unchanged measurements are reused. Buttons have a native background, focus ring and pointer/keyboard activation.
`Page()`, `TextBlock(...)`, `Row(...)`, `Column(...)` and `Button(...)` are callable managed type objects; `Page.base` is ContainerBlock and `page.type` is Page. `isInstance(page, Block)` and `isSubtype(Page, Block)` query nominal relations. Object and Type are explicitly bootstrapped in the same GC heap. Ordinary source class declarations, positional field construction, member assignment and inherited method dispatch are supported; source subclasses of concrete native visual types now reuse their real native allocator; abstract types remain unconstructible. Traits are still pending. Native visual methods now live on their nominal type tables and use the same receiver binding as source methods. See [managed-types.endor](examples/managed-types.endor), [classes.endor](examples/classes.endor) and [native-subclasses.endor](examples/native-subclasses.endor).

Source native subclass construction takes native arguments first, followed by all inherited and own declared fields. For example, a TextBlock subclass with one field accepts `CustomText("text", 2, "#242422", fieldValue)`; optional native arguments can be omitted before the required field suffix. Field storage belongs to the current shared Block content: replacement updates aliases and bindings and releases the previous fields through Aster. This is an implementation subset; field annotations are not yet runtime checked.

Events use `block.on("click", callback)` or `block.on("click", callback, "capture")`, returning a managed Subscription with `disconnect()` and `isConnected()`. A Block owns its connections; tokens refer to connections weakly and do not retain the target or callback. Dropping a token leaves the listener registered. Disconnection releases the callback and is safe to repeat.

`block.dispatch(Event("custom"))` returns the dispatched Event. `block.click()` creates a click Event and uses the same dispatcher as native activation. An optional Mount selects one occurrence: `block.dispatch(event, mount)` or `block.click(mount)`. Without a Mount only the target is visited. With one, capture walks from Page through ancestors, then target capture, the object's `onEvent(self, event)` method and target listeners, then ancestors/Page in bubble order. The target method runs before non-capture target listeners. Event fields expose `kind`, `target`, `mount`, `currentTarget`, `currentMount` and `phase` (`capture`, `target`, `bubble`, then `none`). Source subclasses can override onEvent.

Event methods `stopPropagation()`, `stopImmediatePropagation()`, `preventDefault()` and `isDefaultPrevented()` control delivery or report cancellation; there is currently no additional host default action to cancel. stopPropagation permits remaining listeners on the current occurrence, while the immediate variant stops them too. Listener order is snapshotted at dispatch start; disconnection before a listener's turn skips it, new connections wait for the next dispatch. The existing onClick setter remains a single compatibility callback, called after other non-capture listeners on that Block. All handlers share the VM call budget, with an explicit 10000-delivery limit that reports failure instead of truncating propagation. Reentrant dispatch of the same active Event is rejected; a completed Event can be reused. See [events.endor](examples/events.endor).

Toggle developer tools with Command-Option-I or F12 on macOS, Control-Shift-I or
F12 on Windows/Linux. The compact Console, Sources, Network and Settings tabs
share a draggable dock edge. The Sources tree/source
boundary and Network's request/details boundary can also be dragged. Each content
area has independent vertical and horizontal scrolling, draggable scrollbar thumbs,
and trackpad support. Shift-wheel scrolls horizontally. Layout uses logical pixels
and the actual display scale; resize clamps pane sizes to keep controls reachable.

Console is one live execution context: statements, function definitions and
expressions use the same VM and globals dictionary across submissions. There is no
Expression/Script selector. The current prompt, submitted commands and results
share one scrollable surface, with no separate input box, editor splitter or Run
toolbar. Typing appears at the prompt immediately; Enter executes it and the result
appears directly below. Shift-Enter inserts a newline. Each command and its result
are followed by a thin neutral horizontal separator. Input focus uses a text caret,
without a blue field border or hover fill. The prompt, history and caret share the
same scroll offset; typing and cursor navigation reveal the current insertion point.
Create objects with bare assignment or `let`, then mount them when ready:

```endor
title = ui.text("你好，Tessera", 2, "#243047")
```

At this point the object exists in Console memory and the page stays unchanged.
Later inputs can refer to it:

```endor
note = ui.text("这是 Endor 渲染的页面", 1, "#637082")
card = ui.rect(320, 100, 16, "#DCE8FF")
page = ui.page()
page.render(ui.column(24, 16, title, note, card))
```

Ordinary values keep normal name assignment. UI references opt into Aster's
managed `ObjectPayload::assignment_cell` protocol: assigning another UI object updates the
existing shared reference and preserves its identity. Aliases and mounted parents
therefore observe the same replacement, including across function-local slots.
For example, after `other = card` and `page.render(other)`, assigning
`card = ui.rect(640, 200, 32)` updates the page without another render. This is
shared-reference semantics, not variable-name tracking. Assigning a non-UI value
uses normal value assignment; it does not unmount the old UI reference.

`page.render(root)` mounts a live root and selects its page. Changes to mounted
references publish a new frame after a successful input; unrelated objects do not.
`page.unmount()` releases that page's mount and clears the frame if it was active.
Replacing a container updates its whole mounted position. Repeated aliases are
allowed; replacements that would create a cycle or exceed graph limits are rejected
before mutation. Scalar constructor arguments are evaluated once, as ordinary values.

Bare assignment creates/updates a name; `let` remains a declaration. Aster owns this
syntax, AST and bytecode; Tessera never inserts `let` or replays history. The actual
last value is also bound to `_`. Text editing supports cursor positioning, arrow
keys, Home/End, grapheme-safe deletion, select-all, macOS copy/cut/paste and IME.
Up/Down recall single-line history; Command/Control-Up/Down recall multiline history.

Console sends `POST /v1/namespaces/app.main/repl` as UTF-8 text/plain. Responses
include value, session/input IDs, bindings, `persistent: true`, rendered flag and
revision. Before the first mount, object creation never publishes a page or advances revision.
After mounting, changed shared UI references publish automatically. The last explicit
render in an input selects the active page, only after that input succeeds. Syntax and
compilation errors run no statements; runtime errors can retain earlier successful
statements from that input, while preserving the previously displayed page.

Reset session (`DELETE .../repl`) drops the VM and all bindings/objects, preserving
the displayed immutable frame. Clear only hides the transcript. Limits per session
are 256 executed inputs, 1 MiB transcript, 10000 cumulative AST nodes, 4096 UI nodes
and 64 retained pages. Unreachable objects and cycles are reclaimed between inputs; reset releases the whole session. Code and objects are never stored on disk.

Existing `PUT .../code` remains a complete program replacement with a fresh VM;
function-only source still invokes main. On success the new VM remains live for Console and GUI events; a failed replacement preserves the old VM. Accepted PUT/code DELETE invalidate older queued Console inputs. The compatibility `POST .../evaluate`
endpoint remains isolated for existing clients, but is not a Console mode. All use
the bounded eight-entry worker queue. GET /code returns the displayed source: exact
PUT source, or annotated Console transcript after a REPL render, distinguished by
`X-Tessera-Source-Kind`. The transcript shows actual executed input and can contain
failed statements; it is not guaranteed to replay as a standalone program.

External HTTP activity appears in the same transcript. Unsupported language
operations (currently numeric arithmetic bytecode) show actual diagnostics. Transport
failures appear in the Console footer and restore an otherwise empty draft.

Sources shows the full source snapshot or Console transcript with line numbers, Aster's
AST and selected source ranges. Selecting an AST node scrolls to its location while
keeping the entire file available. Cloud files has a separate file navigator and
source viewer, initially disconnected. The `CloudSourceProvider` boundary in
`src/sources.rs` supplies file identities/paths and full source on open; there is no
cloud backend, fake file listing or source persistence in this release.

Network observes only HTTP requests handled by this Tessera process on
`127.0.0.1:4737`, including pending requests, method, path, status, server duration,
request/response headers and bodies. Filter matches method, path or status. Clear
clears the Network view without changing the document or Console transcript. A bounded
ring retains 80 requests with explicitly marked 32 KiB body previews. Request
headers are allowlisted to Content-Type and Content-Length; credentials and cookies
are not captured. No external browser or operating-system traffic is represented.
Console and Network share the bounded capture ring and have independent clear
markers. Clicking a Console record opens its Network details and restores that view.

Settings applies six accent presets or a custom six-digit hex color immediately.
Very bright custom colors are darkened to keep accents visible on white. Execution
separators, selected tabs and focus indicators use the accent, while text keeps its
readable neutral/error/success colors. Settings and source remain in memory only.

Management controls use the internal [Tessera System UI](src/system_ui/README.md)
widget library, independent of Endor-controlled page widgets. Buttons, tabs,
toggles, rows, input fields, color swatches and drag handles share hover, pressed,
selected, focus and disabled presentation. Buttons activate on release inside;
dragging outside cancels. Tab/Shift-Tab navigate enabled controls and Enter/Space
activate focused buttons. Plain Tab still indents at the Console prompt. Empty
Clear actions are disabled. Splitters are painted and registered above all pane
backgrounds, toolbars and status bars, so their entire length stays visible and
draggable. macOS clipboard reads and writes explicitly use
UTF-8 even when launched from Finder, and decoding errors are surfaced.

## Validation

Local native builds and window runs are allowed; do not run local automated tests
or Docker. [Remote CI](.gitea/README.md) on ces-control runs the existing renderer
checks and the new Aster script/module execution, page rendering, UI layout, source-range, lifetime, budget,
failed-update and deletion-invalidation regressions, plus Clippy.
The API regressions use actual HTTP requests, including DELETE while the worker
is occupied and a queued PUT is superseded.
Linux CI does not verify macOS window presentation. Aster has no standalone CI/CD; Lyra CI
explicitly validates the pinned engine itself. CI uses official Cargo sources
and standard HTTPS checkout without custom SSH secrets. Font checks cover
proportional/monospace advances, fractional scaling, multiline height, Chinese
fallback, grapheme-safe truncation, antialiasing and alpha blending.