package main

import (
	"strings"
	"testing"
	"time"
)

// TestTimeContextFor verifies the time-of-day bucketing used for greetings.
func TestTimeContextFor(t *testing.T) {
	cases := []struct {
		hour     int
		expected string
	}{
		{3, "night"},      // hours < 5
		{5, "morning"},    // 5 <= h < 12
		{11, "morning"},   //
		{12, "afternoon"}, // 12 <= h < 18
		{17, "afternoon"}, //
		{18, "evening"},   // 18 <= h < 22
		{21, "evening"},   //
		{22, "night"},     // h >= 22
		{23, "night"},     //
	}
	for _, tc := range cases {
		// Build the timestamp in the host's local zone so timeContextFor (which
		// reads local time) observes exactly tc.hour regardless of the test
		// machine's timezone.
		ts := int(time.Date(2025, 5, 15, tc.hour, 0, 0, 0, time.Local).Unix())
		if got := timeContextFor(ts); got != tc.expected {
			t.Errorf("timeContextFor(hour=%d) = %q, want %q", tc.hour, got, tc.expected)
		}
	}
}

// TestBuildUserContext verifies the per-turn context block reflects the user's
// details and applies the documented fallbacks.
func TestBuildUserContext(t *testing.T) {
	noon := int(time.Date(2025, 5, 15, 12, 0, 0, 0, time.Local).Unix())

	// Fully-populated premium user.
	got := buildUserContext("alice", "Alice", "Smith", true, "de", noon)
	for _, want := range []string{"Alice Smith", "@alice", "Preferred language: de", "premium user", "afternoon"} {
		if !strings.Contains(got, want) {
			t.Errorf("buildUserContext premium: missing %q in:\n%s", want, got)
		}
	}

	// Missing name/username/language fall back; non-premium reads "regular user".
	got = buildUserContext("", "", "", false, "", noon)
	for _, want := range []string{"User: unknown (Telegram @unknown)", "Preferred language: en", "regular user"} {
		if !strings.Contains(got, want) {
			t.Errorf("buildUserContext fallback: missing %q in:\n%s", want, got)
		}
	}

	// First name only (no last name) must not leave a trailing space in the name.
	got = buildUserContext("bob", "Bob", "", false, "en", noon)
	if !strings.Contains(got, "User: Bob (Telegram @bob)") {
		t.Errorf("buildUserContext firstname-only: got:\n%s", got)
	}
}