# `flanger/schemas`

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_(no submodules)_
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## Purpose

Zod schemas validating the construction-time options and preset payload of `FlangerPlugin`. These run on the public boundary between user code and the plugin: any malformed object hitting the constructor or `applyPreset` is rejected with `AUDIO_FX.INVALID_OPTIONS` / `AUDIO_FX.INVALID_PRESET` before it can corrupt runtime state.

Separating schemas from the plugin module lets `index.ts` re-export them so callers can introspect the option surface for forms, RPC validation, or storybook controls without importing the audio implementation.

## Features

- `FlangerPluginOptionsSchema` — validates all five optional construction fields with their documented ranges (`rate` 0.05..10 Hz, `depth` 0..5 ms, `feedback` 0..0.95, `wet` 0..1, `baseDelay` 0.1..10 ms).
- `FlangerPresetDataSchema` — empty strict object: the flanger has no plugin-specific preset payload, so any extra keys are rejected by `.strict()`.
- All numeric fields use `z.number().finite()` so `NaN` and `Infinity` cannot sneak through.

## Usage: Basic Example

```ts
import { FlangerPluginOptionsSchema } from "@suaveplan/audio-fx-plugin-flanger";

const parsed = FlangerPluginOptionsSchema.parse({ initialDepthMs: 1.5 });
```

## Usage: Advanced Example

```ts
import {
    FlangerPluginOptionsSchema,
    FlangerPresetDataSchema,
} from "@suaveplan/audio-fx-plugin-flanger";

// Pull keys + ranges from the schema for a generated form.
const fields = FlangerPluginOptionsSchema.keyof().options;
for (const field of fields) {
    form.addRow(field);
}

// Strict preset validation at the IPC boundary.
function isFlangerPreset(blob: unknown): boolean {
    return FlangerPresetDataSchema.safeParse(blob).success;
}
```

## API Reference

- `FlangerPluginOptionsSchema: z.ZodObject<{ initialRateHz?, initialDepthMs?, initialFeedback?, initialWet?, initialBaseDelayMs? }>`
- `FlangerPresetDataSchema: z.ZodObject<{}, "strict">`

## Implementation Notes

The maximum feedback is `0.95`, matching the chorus, phaser, and delay plugins so all four feedback-bearing effects share one mental model. The flanger lives close to that boundary by design — the resonant comb peaks are the effect's character — but the same hard cap keeps the loop strictly under unity gain so the output cannot diverge.

`FlangerPresetDataSchema` is `.strict()` so unknown fields are rejected, matching the sibling-plugin policy. The flanger has no plugin-specific preset payload today: every parameter (`rate`, `depth`, `feedback`, `wet`, `baseDelay`) travels through the universal parameter snapshot that `AbstractAudioFxPlugin` builds, and the empty `presetData` field marks that the plugin opts out of plugin-specific state.