ersteller/starter/AGENTS.md

# Development Guidelines

## Styling

Every page has styling in a separate CSS file.

- Page-specific styles should be placed in separate CSS files in the `static/` directory
- Example: The media page has its styles in `static/media.css`
- General/shared styles are in `static/styles.css`

## Single Page Implementation

### Path constants

- Define path constants for the root paths of the page only (not for sub-routes).

```go
const MediaPath = "/media"
const MediaPathDe = "/medien"
```

### Page struct and initializer

- Define a `Page` struct that contains all routes and actions as fields.
- Initialize routes in the `NewPage` constructor function.

```go
type Page struct {
    // Routes
    ViewRoute   HtmxRoute
    StartRoute  HtmxRoute
    StopRoute   HtmxRoute

}

func NewPage(server *Server) *Page {
    p := &Page{}

    // Initialize routes
    p.ViewRoute = NewHtmxGetRoute(p.View, LanguagePaths{En: MediaPath, De: MediaPathDe}).SetActivePath(MediaPath)
    p.StartRoute = NewHtmxPostRoute(p.Start, LanguagePaths{En: MediaPath + "/start", De: MediaPathDe + "/start"})
    p.StopRoute = NewHtmxPostRoute(p.Stop, LanguagePaths{En: MediaPath + "/stop", De: MediaPathDe + "/stop"})

    // Register routes
    p.ViewRoute.Add(server)
    p.StartRoute.Add(server)
    p.StopRoute.Add(server)

    return p
}
```

### Multilingual content (`I18nText`)

- Declare user-facing text with `I18nText`; avoid hardcoded strings.
- Create a separate `Texts` struct type and initialize it in a `createTexts()` function.

```go
var texts *Texts

type Texts struct {
    PageTitle       I18nText
    PageDescription I18nText
    HeroTitle       I18nText
    StartProcessing I18nText
}

func createTexts() {
    texts = &Texts{
        PageTitle:       NewI18nText(map[Language]string{En: "Media Processing", De: "Medienverarbeitung"}),
        PageDescription: NewI18nText(map[Language]string{En: "Process and organize your media files", De: "Verarbeiten und organisieren Sie Ihre Mediendateien"}),
        HeroTitle:       NewI18nText(map[Language]string{En: "Media Processing", De: "Medienverarbeitung"}),
        StartProcessing: NewI18nText(map[Language]string{En: "Start Processing", De: "Verarbeitung starten"}),
    }
}

func (p *Page) getMetaData() PageWebsiteMetaData {
    return PageWebsiteMetaData{
        Title:       texts.PageTitle,
        Lang:        En,
        Description: texts.PageDescription,
        StyleSrcs:   []string{"/static/media.css"},
    }
}

func (p *Page) View(c HtmxContext) {
    lang := c.GetLanguage()
    content := Group{
        Div(Class("hero"),
            H1(Text(texts.HeroTitle.FromLang(lang))),
        ),
    }
    p.createPage(c, p.getMetaData(), content)
}
```

### Language-aware URLs and hx attributes

- Derive URLs from routes with the active language for all hx attributes.

```go
lang := c.GetLanguage()

Button(
    Text(texts.StartProcessing.FromLang(lang)),
    p.StartRoute.GetHtmx(lang),
    hx.Target("body"),
)

// Pagination example with hx.PushURL to keep browser URL in sync
Button(
    Text(texts.Next.FromLang(lang)),
    hx.Get(p.RefreshRoute.ToUrlFromContext(c, lang)),
    hx.PushURL(p.ViewRoute.ToUrlFromContext(c, lang)),
    hx.Target("#queue-contents"),
    hx.Swap("innerHTML"),
)
```

### Page assembly and styles

- Build pages with `createPage` and supply metadata plus styles.
- Create a `getMetaData()` function to centralize page metadata configuration.
- Keep shared CSS in `static/styles.css` and page-specific CSS in `static/<page>.css`; include via `StyleSrcs`.

```go
func (p *Page) getMetaData() PageWebsiteMetaData {
    return PageWebsiteMetaData{
        Title:       texts.PageTitle,
        Lang:        En,
        Description: texts.PageDescription,
        StyleSrcs:   []string{"/static/media.css"},
    }
}

func (p *Page) View(c HtmxContext) {
    lang := c.GetLanguage()
    content := Group{
        Div(Class("hero"), H1(Text(texts.HeroTitle.FromLang(lang)))),
        // ... more components ...
    }

    p.createPage(c, p.getMetaData(), content)
}
```

### HTMX partials and polling

- Use HTMX forms and partial refreshes; combine `hx.Target`, `hx.Swap`, and periodic polling (`hx.Trigger("every 5s")`) with language-aware URLs.

```go
// Partial that refreshes every 5s when running
Group{
    hx.Get(p.RefreshStatusRoute.ToUrlFromContext(c, lang)),
    hx.Trigger("every 5s"),
    hx.Target("#queue-status"),
    hx.Swap("innerHTML"),
}

Form(
    p.SaveSettingsRoute.GetHtmx(lang),
    hx.Target("body"),
    // form fields...
)

// Use GetHtmx() for form actions to ensure proper HTMX attributes
Form(
    p.localLoginRoute.GetHtmx(language),
    hx.Target("body"),
    // form fields...
)
```

## HTMX Routes

**ALWAYS** prefer using `p.Route.GetHtmx()` over directly calling `hx.Get(p.Route.ToUrlFromContext())`.

**Example:**
- ✅ Preferred: `p.RefreshStatusRoute.GetHtmx(c, lang)`
- ❌ Avoid: `hx.Get(p.RefreshStatusRoute.ToUrlFromContext(c, lang))`

## Persisting Data with Ent Schemas

### Schema Definition

- Define schemas in `ent/schema/<entity>.go`
- Each schema is a struct that embeds `ent.Schema`
- Use the `TimeMixin` to automatically add `created_at` and `updated_at` fields

```go
package schema

import (
	"entgo.io/ent"
	"entgo.io/ent/schema/field"
	"entgo.io/ent/schema/edge"
)

type Media struct {
	ent.Schema
}

// Apply TimeMixin for automatic timestamp fields
func (Media) Mixin() []ent.Mixin {
	return []ent.Mixin{
		TimeMixin{},
	}
}

// Define fields
func (Media) Fields() []ent.Field {
	return []ent.Field{
		field.String("filename"),
		field.String("hash"),
		field.String("description").Default(""),
		field.Time("created_date").Optional().Nillable(),
		field.Int("year").Optional().Nillable(),
		field.Float("gps_latitude").Optional().Nillable(),
	}
}

// Define relationships
func (Media) Edges() []ent.Edge {
	return []ent.Edge{
		edge.To("tags", Tag.Type),  // Many-to-Many
	}
}
```

### Field Types and Options

**Common field types:**
- `field.String("name")` - string field
- `field.Int("count")` - integer field
- `field.Float("latitude")` - float64 field
- `field.Bool("active")` - boolean field
- `field.Time("date")` - time.Time field

**Field modifiers:**
- `.Default(value)` - set default value
- `.Optional()` - field can be omitted on creation
- `.Nillable()` - field can be nil (must be used with Optional)
- `.Immutable()` - field cannot be updated after creation
- `.Unique()` - field value must be unique

### Generating Code

After modifying schemas, regenerate the ent code:

```bash
go run generate_schema.go
```

### Usage in Handlers

**Create:**
```go
media, err := server.Client.Media.Create().
	SetFilename("photo.jpg").
	SetHash("abc123").
	SetDescription("Vacation photo").
	Save(c.Request.Context())
```

**Query:**
```go
// Get by ID
media, err := server.Client.Media.Get(c.Request.Context(), id)

// Query with filters
medias, err := server.Client.Media.Query().
	Where(media.YearEQ(2024)).
	All(c.Request.Context())

// Query with edges
medias, err := server.Client.Media.Query().
	WithTags().  // Load tags relationship
	All(c.Request.Context())
```

**Update:**
```go
err := server.Client.Media.UpdateOneID(id).
	SetDescription("Updated description").
	Save(c.Request.Context())
```

**Delete:**
```go
err := server.Client.Media.DeleteOneID(id).
	Exec(c.Request.Context())
```

### Relationships (Edges)

**One-to-Many:**
```go
edge.To("posts", Post.Type)  // User has many posts
edge.From("owner", User.Type).Ref("posts").Unique()  // Post belongs to one user
```

**Many-to-Many:**
```go
edge.To("tags", Tag.Type)  // Media has many tags
edge.From("media", Media.Type).Ref("tags")  // Tag has many media
```

## Important Instructions

Do what has been asked; nothing more, nothing less.

**NEVER** create files unless they're absolutely necessary for achieving your goal.

**ALWAYS** prefer editing an existing file to creating a new one.

**NEVER** proactively create documentation files (`*.md`) or README files. Only create documentation files if explicitly requested by the User.