…#196295)

With [PR elastic#187475](https://github.com/elastic/kibana/pull/187475/files)
we introduced a bug, affecting the AI assistant's suggestions API when
switching between different chart types (e.g., from bar to line chart).
This feature relies on the switchVisualizationType method, which was
changed to require a `layerId`. However, the suggestions API does not
provide `layerId`, causing the chart type to not switch as expected.

Solution:
The bug can be resolved by modifying the logic in the
`switchVisualizationType` method. We changed:

```ts
const dataLayer = state.layers.find((l) => l.layerId === layerId);
```

to:

```ts
const dataLayer = state.layers.find((l) => l.layerId === layerId) ?? state.layers[0];
```

This ensures that the suggestions API falls back to the first layer if
no specific layerId is provided.

---------

Co-authored-by: Marco Vettorello <[email protected]>
(cherry picked from commit e476220)

…196295) (#196448)

# Backport

This will backport the following commits from `main` to `8.x`:
- [[Lens] Fix switchVisualizationType to use it without layerId
(#196295)](#196295)

<!--- Backport version: 9.4.3 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sqren/backport)

<!--BACKPORT [{"author":{"name":"Marta
Bondyra","email":"[email protected]"},"sourceCommit":{"committedDate":"2024-10-15T21:53:00Z","message":"[Lens]
Fix switchVisualizationType to use it without layerId (#196295)\n\nWith
[PR #187475](https://github.com/elastic/kibana/pull/187475/files)\r\nwe
introduced a bug, affecting the AI assistant's suggestions API
when\r\nswitching between different chart types (e.g., from bar to line
chart).\r\nThis feature relies on the switchVisualizationType method,
which was\r\nchanged to require a `layerId`. However, the suggestions
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as expected.\r\n\r\nSolution:\r\nThe bug can be resolved by modifying
the logic in the\r\n`switchVisualizationType` method. We
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l.layerId === layerId);\r\n```\r\n\r\nto:\r\n\r\n```ts\r\nconst
dataLayer = state.layers.find((l) => l.layerId === layerId) ??
state.layers[0];\r\n```\r\n\r\nThis ensures that the suggestions API
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Fix switchVisualizationType to use it without
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Fix switchVisualizationType to use it without layerId (#196295)\n\nWith
[PR #187475](https://github.com/elastic/kibana/pull/187475/files)\r\nwe
introduced a bug, affecting the AI assistant's suggestions API
when\r\nswitching between different chart types (e.g., from bar to line
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which was\r\nchanged to require a `layerId`. However, the suggestions
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as expected.\r\n\r\nSolution:\r\nThe bug can be resolved by modifying
the logic in the\r\n`switchVisualizationType` method. We
changed:\r\n\r\n```ts\r\nconst dataLayer = state.layers.find((l) =>
l.layerId === layerId);\r\n```\r\n\r\nto:\r\n\r\n```ts\r\nconst
dataLayer = state.layers.find((l) => l.layerId === layerId) ??
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Fix switchVisualizationType to use it without layerId (#196295)\n\nWith
[PR #187475](https://github.com/elastic/kibana/pull/187475/files)\r\nwe
introduced a bug, affecting the AI assistant's suggestions API
when\r\nswitching between different chart types (e.g., from bar to line
chart).\r\nThis feature relies on the switchVisualizationType method,
which was\r\nchanged to require a `layerId`. However, the suggestions
API does not\r\nprovide `layerId`, causing the chart type to not switch
as expected.\r\n\r\nSolution:\r\nThe bug can be resolved by modifying
the logic in the\r\n`switchVisualizationType` method. We
changed:\r\n\r\n```ts\r\nconst dataLayer = state.layers.find((l) =>
l.layerId === layerId);\r\n```\r\n\r\nto:\r\n\r\n```ts\r\nconst
dataLayer = state.layers.find((l) => l.layerId === layerId) ??
state.layers[0];\r\n```\r\n\r\nThis ensures that the suggestions API
falls back to the first layer if\r\nno specific layerId is
provided.\r\n\r\n---------\r\n\r\nCo-authored-by: Marco Vettorello
<[email protected]>","sha":"e4762201fdd84f372c78bc2a159061e504b26e78"}}]}]
BACKPORT-->

Co-authored-by: Marta Bondyra <[email protected]>