feat: add --time mode for using 24h time format

cmd/tz-snipe/main.go

@@ -18,6 +18,8 @@ func main() {
 	tzFlag := flag.String("tz", "", "Timezone like +1000")
 	// --github mode
 	ghFlag := flag.String("github", "", "From a github username")
+	// --time mode
+	timeFlag := flag.String("time", "", "Time like 15:00")
 
 	flag.Parse()
 
@@ -29,17 +31,24 @@ func main() {
 	}
 
 	// 3. checks
-	if *tzFlag != "" && *ghFlag != "" {
-		fmt.Println("Cannot use both --tz and --github modes")
+	modes := 0
+	for _, val := range []string{*tzFlag, *ghFlag, *timeFlag} {
+		if val != "" {
+			modes++
+		}
+	}
+
+	if modes > 1 {
+		fmt.Println("Cannot use multiple modes at once")
 		os.Exit(1)
 	}
-	if *tzFlag == "" && *ghFlag == "" {
-		fmt.Println("Both args empty... exiting")
+	if modes == 0 {
+		fmt.Println("No args provided... exiting")
 		os.Exit(1)
 	}
 
 	// 4. exec
-	p := tea.NewProgram(ui.NewModel(db, *ghFlag, *tzFlag))
+	p := tea.NewProgram(ui.NewModel(db, *ghFlag, *tzFlag, *timeFlag))
 	if _, err := p.Run(); err != nil {
 		// I keep on forgetting, fmt.ErrorF makes an error, does not print
 		fmt.Printf("Error: %v", err)

internal/core/time.go

@@ -0,0 +1,33 @@
+package core
+
+import (
+	"time"
+	"tz-snipe/internal/geodata"
+)
+
+func GetTZsMatchingTime(db geodata.TimezoneMap, targetTime string) ([]string, error) {
+	// another go quirK: for layout it uses a fixed point in time
+	// as reference date Mon, 1/2 03:04:05 PM 2006 -0700
+	// 1 2 3 4 5 6 7
+	if _, err := time.Parse("15:04", targetTime); err != nil {
+		return nil, err
+	}
+
+	now := time.Now().UTC()
+	var matches []string
+
+	for tz := range db {
+		// Parse offset to location
+		zoneTime, err := time.Parse("-0700", tz)
+		if err != nil {
+			continue
+		}
+
+		// Check if the formatted string matches exactly
+		// same minute match
+		if now.In(zoneTime.Location()).Format("15:04") == targetTime {
+			matches = append(matches, tz)
+		}
+	}
+	return matches, nil
+}

internal/ui/model.go

@@ -29,7 +29,7 @@ var _ tea.Model = Model{}
 // REMINDER REMINDER REMINDER
 // Model, NewModel, Init, Commands, Update, View is all you need
 
-func NewModel(db geodata.TimezoneMap, ghUser, manualTz string) Model {
+func NewModel(db geodata.TimezoneMap, ghUser, manualTz, targetTime string) Model {
 	m := Model{
 		db:              db,
 		username:        ghUser,
@@ -46,6 +46,23 @@ func NewModel(db geodata.TimezoneMap, ghUser, manualTz string) Model {
 			m.table = newTable(m.preds)
 			m.displayTz = m.manualTz
 		}
+	case targetTime != "":
+		// Logic for time matching
+		tzs, err := core.GetTZsMatchingTime(db, targetTime)
+		if err != nil {
+			m.err = err
+		} else if len(tzs) == 0 {
+			m.err = fmt.Errorf("no timezones found matching %s", targetTime)
+		} else {
+			preds, err := core.GetStatsForTZs(tzs)
+			if err != nil {
+				m.err = err
+			} else {
+				m.preds = preds
+				m.table = newTable(m.preds)
+				m.displayTz = targetTime
+			}
+		}
 	case ghUser != "":
 		m.loadingGithubTz = true
 	}