Modernize fSpy: Full Stack Upgrade & Bug Fixes

.eslintrc.json

@@ -0,0 +1,40 @@
+{
+  "root": true,
+  "parser": "@typescript-eslint/parser",
+  "parserOptions": {
+    "ecmaVersion": 2022,
+    "sourceType": "module",
+    "ecmaFeatures": {
+      "jsx": true
+    }
+  },
+  "plugins": ["@typescript-eslint"],
+  "extends": [
+    "eslint:recommended",
+    "plugin:@typescript-eslint/recommended"
+  ],
+  "rules": {
+    "indent": ["warn", 2, { "SwitchCase": 1 }],
+    "eqeqeq": "off",
+    "prefer-const": "off",
+    "no-case-declarations": "off",
+    "space-before-function-paren": ["error", {
+      "anonymous": "always",
+      "named": "never",
+      "asyncArrow": "ignore"
+    }],
+    "@typescript-eslint/no-unused-vars": "off",
+    "@typescript-eslint/no-explicit-any": "off",
+    "@typescript-eslint/no-var-requires": "off",
+    "@typescript-eslint/explicit-function-return-type": "off",
+    "@typescript-eslint/explicit-module-boundary-types": "off",
+    "@typescript-eslint/no-non-null-assertion": "off",
+    "@typescript-eslint/ban-types": "off"
+  },
+  "env": {
+    "browser": true,
+    "node": true,
+    "es2022": true
+  },
+  "ignorePatterns": ["build/", "node_modules/", "__tests__/", "*.js"]
+}

AGENTS.md

@@ -0,0 +1,67 @@
+# AGENTS.md — fSpy Project Guide
+
+## Project Overview
+
+fSpy is a cross-platform Electron 42 desktop application for camera matching from still images. It uses React 18, Konva 9 / react-konva 18 for canvas rendering, Redux 5 for state management, and Webpack 5 for bundling. TypeScript 5.8 with strict mode. Licensed under GPL-3.0.
+
+## Architecture
+
+### Process model
+
+- **Main process** (`src/main/index.ts`): Electron lifecycle, window management, IPC handlers, all file system access.
+- **Preload script** (`src/main/preload.ts`): Uses `contextBridge.exposeInMainWorld('electronAPI', ...)` to expose a typed API surface to the renderer. Kept minimal.
+- **Renderer** (`src/gui/`): React/Redux UI. Has **no** direct access to Node.js APIs or Electron internals — all system access goes through `window.electronAPI`.
+
+### Security model
+
+- `contextIsolation: true`, `nodeIntegration: false`, `sandbox: true`.
+- No `remote` module. No `eval()` or `new Function()` in renderer code.
+- IPC pattern: `ipcMain.handle` / `ipcRenderer.invoke` for request-response; `ipcMain.on` / `ipcRenderer.send` for fire-and-forget.
+- Do not expose raw `ipcRenderer` to the renderer. Add new IPC channels to `src/main/preload.ts` and `src/gui/types/electron-api.ts`.
+
+### Build targets
+
+Webpack produces three bundles (see `webpack.config.js`):
+1. `main` — target `electron-main`
+2. `gui` — target `web` (renderer, no Node.js externals)
+3. `preload` — target `electron-preload`
+
+## Code Style
+
+- TypeScript strict mode. Do not add `@ts-ignore` or `any` to work around type issues — fix the types properly.
+- Prefer `const` over `let`. Never use `var`.
+- Use ES module import syntax (`import`/`export`), not `require()`, in TypeScript source files.
+- Indent with 2 spaces. LF line endings.
+- Do not add comments or JSDoc to unchanged code.
+- Do not refactor or "improve" code beyond what is necessary for the task at hand.
+
+## Component Patterns
+
+- Existing class components do not need to be converted to function components unless required by a dependency change.
+- Do not introduce new class components. Any new code should use function components with hooks.
+- Redux: existing `connect()` + `legacy_createStore` pattern is in use. Action type strings are stable — do not rename them.
+
+## Project File Format
+
+- The `.fspy` binary format is documented in `project_file_format.md` and must remain backward-compatible.
+- Existing `.fspy` files in `test_data/` must load correctly after any code changes.
+- File I/O in the renderer uses `DataView`/`Uint8Array`/`TextEncoder`/`TextDecoder` (no `Buffer`).
+
+## Testing
+
+- Tests live in `tests/` and run via Jest 29 + ts-jest. Config in `jest.config.js`.
+- Run: `npm test`.
+- Test with the `.fspy` files in `test_data/` to verify project file compatibility.
+
+## Dependencies
+
+- **License**: GPL-3.0. Do not introduce dependencies with incompatible licenses (SSPL, proprietary, AGPL). Prefer MIT/Apache-2.0/BSD/ISC.
+- Pin major versions in `package.json` (e.g., `^5.8.0`, not `*` or `latest`).
+- Run `npm audit` after dependency changes and fix critical/high vulnerabilities before merging.
+- Prefer well-maintained packages with recent releases.
+
+## File Structure
+
+- Do not restructure the `src/` directory layout unless a dependency requires it.
+- Preload script source: `src/main/preload.ts`.
+- Electron API type definitions: `src/gui/types/electron-api.ts`.

AUTHORS.md

@@ -0,0 +1,12 @@
+# Authors
+
+## Creator and original author
+
+- **Per Gantelius** ([@stuffmatic](https://github.com/stuffmatic))
+
+## Contributors
+
+- **Darío Hereñú** ([@kant](https://github.com/kant))
+- **Tuk Bredsdorff** ([@tiktuk](https://github.com/tiktuk))
+- **Luis García-Tornel**
+- **Leon Zandman** ([@leonzandman](https://github.com/leonzandman))

README.md

@@ -27,12 +27,12 @@ To install necessary dependencies, run
 yarn
 ```
 
-The `src` folder contains two subfolders `main` and `gui`, containing code for the [Electron main and renderer processes](https://electronjs.org/docs/tutorial/application-architecture) respectively.
+The `src` folder contains three subfolders: `main` and `gui`, containing code for the [Electron main and renderer processes](https://electronjs.org/docs/tutorial/application-architecture) respectively, and `cli`, which contains a command-line interface for processing fSpy project files without the GUI. The main process includes a preload script (`src/main/preload.ts`) that bridges the renderer and main processes via IPC.
 
 Here's how to run the app in development mode
 
 1. Run `yarn dev-server` in a separate terminal tab to start the dev server
-2. Run `yarn build-dev` to build both the main and GUI code. This build step is needed to generate main process code used to start up the app.
+2. Run `yarn build-dev` to build the main, preload, and GUI code. This build step is needed to generate main process and preload code used to start up the app.
 3. Run `yarn electron-dev` in a separate terminal tab to start an Electron instance which uses the dev server to provide automatic reloading on GUI code changes.
 
 ⚠️ The current build process is not ideal. For example, it lacks support for live reloading on main process code changes. Changes to main process code require a manual rebuild, i.e steps 2-3, in order to show up in the app.
@@ -47,3 +47,5 @@ yarn dist
 ```
 
 which invokes [Electron builder](https://github.com/electron-userland/electron-builder).
+
+⚠️ The `yarn dist` script builds for macOS, Windows, and Linux (`-mwl`). Building for macOS requires running on macOS. To build only for the current platform, run `yarn dist-preview` instead (output in `dist/` without packaging).

jest.config.js

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+/** @type {import('jest').Config} */
+module.exports = {
+  preset: 'ts-jest',
+  testEnvironment: 'node',
+  roots: ['<rootDir>/tests'],
+  testMatch: ['**/*tests.ts', '**/*specs.ts'],
+  reporters: ['default', 'jest-junit']
+}