package chromedp
import (
"context"
"strings"
"github.com/chromedp/cdproto/emulation"
"github.com/chromedp/chromedp"
)
// ViewportPreset defines a standard viewport configuration for responsive testing.
type ViewportPreset struct {
Name string // Preset name (e.g., "mobile-portrait")
Width int64 // Viewport width in pixels
Height int64 // Viewport height in pixels
Scale float64 // Device scale factor (e.g., 2.0 for retina)
Mobile bool // Emulate mobile device
Touch bool // Enable touch events
}
// DefaultViewports contains the 6 standard viewport presets for responsive testing.
var DefaultViewports = []ViewportPreset{
{
Name: "mobile-portrait",
Width: 375,
Height: 667,
Scale: 2.0,
Mobile: true,
Touch: true,
},
{
Name: "mobile-landscape",
Width: 667,
Height: 375,
Scale: 2.0,
Mobile: true,
Touch: true,
},
{
Name: "tablet-portrait",
Width: 768,
Height: 1024,
Scale: 2.0,
Mobile: true,
Touch: true,
},
{
Name: "tablet-landscape",
Width: 1024,
Height: 768,
Scale: 2.0,
Mobile: true,
Touch: true,
},
{
Name: "desktop",
Width: 1280,
Height: 800,
Scale: 1.0,
Mobile: false,
Touch: false,
},
{
Name: "desktop-large",
Width: 1920,
Height: 1080,
Scale: 1.0,
Mobile: false,
Touch: false,
},
}
// GetViewport retrieves a viewport preset by name with fuzzy matching.
// It supports exact matches, partial matches, and common aliases.
// Returns nil if no matching preset is found.
func GetViewport(name string) *ViewportPreset {
name = strings.ToLower(strings.TrimSpace(name))
if name == "" {
return nil
}
// Define aliases for common terms
aliases := map[string]string{
"phone": "mobile-portrait",
"mobile": "mobile-portrait",
"phone-portrait": "mobile-portrait",
"phone-landscape": "mobile-landscape",
"iphone": "mobile-portrait",
"android": "mobile-portrait",
"tablet": "tablet-portrait",
"ipad": "tablet-portrait",
"ipad-portrait": "tablet-portrait",
"ipad-landscape": "tablet-landscape",
"laptop": "desktop",
"1080p": "desktop-large",
"fullhd": "desktop-large",
"hd": "desktop-large",
}
// Check aliases first
if aliased, ok := aliases[name]; ok {
name = aliased
}
// Try exact match
for i := range DefaultViewports {
if DefaultViewports[i].Name == name {
return &DefaultViewports[i]
}
}
// Try partial match (contains)
for i := range DefaultViewports {
if strings.Contains(DefaultViewports[i].Name, name) {
return &DefaultViewports[i]
}
}
// Try reverse partial match (input contains preset name part)
for i := range DefaultViewports {
parts := strings.Split(DefaultViewports[i].Name, "-")
for _, part := range parts {
if strings.Contains(name, part) {
return &DefaultViewports[i]
}
}
}
return nil
}
// GetViewportByDimensions finds a preset closest to the given dimensions.
// Returns nil if no reasonably close preset is found.
func GetViewportByDimensions(width, height int64) *ViewportPreset {
var best *ViewportPreset
bestDiff := int64(^uint64(0) >> 1) // Max int64
for i := range DefaultViewports {
v := &DefaultViewports[i]
diff := abs(v.Width-width) + abs(v.Height-height)
if diff < bestDiff {
bestDiff = diff
best = v
}
}
// Only return if within reasonable tolerance (200px total)
if bestDiff <= 200 {
return best
}
return nil
}
// ListViewportNames returns the names of all available viewport presets.
func ListViewportNames() []string {
names := make([]string, len(DefaultViewports))
for i, v := range DefaultViewports {
names[i] = v.Name
}
return names
}
// ToEmulateActions converts a ViewportPreset to chromedp emulation actions.
// It uses CDP commands directly to properly set mobile and touch emulation.
func (v *ViewportPreset) ToEmulateActions() chromedp.Tasks {
tasks := chromedp.Tasks{
// Set device metrics with mobile flag
chromedp.ActionFunc(func(ctx context.Context) error {
return emulation.SetDeviceMetricsOverride(v.Width, v.Height, v.Scale, v.Mobile).Do(ctx)
}),
}
// Enable touch emulation if needed
if v.Touch {
tasks = append(tasks, chromedp.ActionFunc(func(ctx context.Context) error {
return emulation.SetTouchEmulationEnabled(true).Do(ctx)
}))
}
return tasks
}
// abs returns the absolute value of an int64.
func abs(n int64) int64 {
if n < 0 {
return -n
}
return n
}
