package main

...

// Add a CurrentYear field to the templateData struct.
type templateData struct {
    CurrentYear int
    Snippet     models.Snippet
    Snippets    []models.Snippet
}

...

package main

import (
    "bytes"
    "fmt"
    "net/http"
    "time" // New import
)

...

// Create an newTemplateData() helper, which returns a templateData struct 
// initialized with the current year. Note that we're not using the *http.Request 
// parameter here at the moment, but we will do later in the book.
func (app *application) newTemplateData(r *http.Request) templateData {
    return templateData{
        CurrentYear: time.Now().Year(),
    }
}

...

package main

...

func (app *application) home(w http.ResponseWriter, r *http.Request) {
    w.Header().Add("Server", "Go")
    
    snippets, err := app.snippets.Latest()
    if err != nil {
        app.serverError(w, r, err)
        return
    }

    // Call the newTemplateData() helper to get a templateData struct containing
    // the 'default' data (which for now is just the current year), and add the
    // snippets slice to it.
    data := app.newTemplateData(r)
    data.Snippets = snippets

    // Pass the data to the render() helper as normal.
    app.render(w, r, http.StatusOK, "home.tmpl", data)
}

func (app *application) snippetView(w http.ResponseWriter, r *http.Request) {
    id, err := strconv.Atoi(r.PathValue("id"))
    if err != nil || id < 1 {
        http.NotFound(w, r)
        return
    }

    snippet, err := app.snippets.Get(id)
    if err != nil {
        if errors.Is(err, models.ErrNoRecord) {
            http.NotFound(w, r)
        } else {
            app.serverError(w, r, err)
        }
        return
    }

    // And do the same thing again here...
    data := app.newTemplateData(r)
    data.Snippet = snippet

    app.render(w, r, http.StatusOK, "view.tmpl", data)
}

...