package httputil

import (
	"net/http"
	"net/http/httptest"
	"testing"
)

func TestLang(t *testing.T) {
	tests := []struct {
		name     string
		query    string
		expected string
	}{
		{"Empty returns default", "", "en"},
		{"English", "?lang=en", "en"},
		{"Spanish", "?lang=es", "es"},
		{"Invalid returns default", "?lang=fr", "en"},
		{"Unknown returns default", "?lang=xyz", "en"},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			req := httptest.NewRequest(http.MethodGet, "/"+tt.query, nil)
			got := Lang(req)
			if got != tt.expected {
				t.Errorf("Lang() = %q, want %q", got, tt.expected)
			}
		})
	}
}

func TestLangOrError(t *testing.T) {
	tests := []struct {
		name     string
		query    string
		expected string
		ok       bool
	}{
		{"Empty returns default", "", "en", true},
		{"English", "?lang=en", "en", true},
		{"Spanish", "?lang=es", "es", true},
		{"Invalid returns error", "?lang=fr", "", false},
		{"Unknown returns error", "?lang=xyz", "", false},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			req := httptest.NewRequest(http.MethodGet, "/"+tt.query, nil)
			got, ok := LangOrError(req)
			if ok != tt.ok {
				t.Errorf("LangOrError() ok = %v, want %v", ok, tt.ok)
			}
			if got != tt.expected {
				t.Errorf("LangOrError() = %q, want %q", got, tt.expected)
			}
		})
	}
}

func TestQuery(t *testing.T) {
	tests := []struct {
		name       string
		query      string
		key        string
		defaultVal string
		expected   string
	}{
		{"Returns value", "?foo=bar", "foo", "default", "bar"},
		{"Returns default when missing", "", "foo", "default", "default"},
		{"Returns default when empty", "?foo=", "foo", "default", "default"},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			req := httptest.NewRequest(http.MethodGet, "/"+tt.query, nil)
			got := Query(req, tt.key, tt.defaultVal)
			if got != tt.expected {
				t.Errorf("Query() = %q, want %q", got, tt.expected)
			}
		})
	}
}

func TestQueryOneOf(t *testing.T) {
	allowed := []string{"short", "long"}

	tests := []struct {
		name       string
		query      string
		defaultVal string
		expected   string
	}{
		{"Returns valid value", "?length=short", "short", "short"},
		{"Returns valid value 2", "?length=long", "short", "long"},
		{"Returns default when invalid", "?length=medium", "short", "short"},
		{"Returns default when empty", "", "short", "short"},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			req := httptest.NewRequest(http.MethodGet, "/"+tt.query, nil)
			got := QueryOneOf(req, "length", allowed, tt.defaultVal)
			if got != tt.expected {
				t.Errorf("QueryOneOf() = %q, want %q", got, tt.expected)
			}
		})
	}
}