package updatecheck

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

func TestIsNewer(t *testing.T) {
	tests := []struct {
		name            string
		current, latest string
		want            bool
	}{
		{"patch bump", "v1.0.85", "v1.0.86", true},
		{"minor beats patch", "v1.0.99", "v1.1.0", true},
		{"major bump", "v1.9.9", "v2.0.0", true},
		{"numeric not lexical", "v1.0.9", "v1.0.10", true},
		{"same", "v1.0.85", "v1.0.85", false},
		{"older latest", "v1.0.86", "v1.0.85", false},
		{"no v prefix", "1.0.1", "v1.0.2", true},
		{"short version", "v1.0", "v1.0.1", true},
		{"prerelease suffix ignored", "v1.0.1-rc1", "v1.0.2", true},
		{"dev build", "dev", "v9.9.9", false},
		{"commit hash", "abc1234", "v9.9.9", false},
		{"empty current", "", "v1.0.0", false},
		{"bad latest", "v1.0.0", "latest", false},
		{"too many parts", "v1.0.0.0", "v1.0.1", false},
		{"negative", "v1.-1.0", "v1.0.0", false},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if got := IsNewer(tt.current, tt.latest); got != tt.want {
				t.Errorf("IsNewer(%q,%q) = %v, want %v", tt.current, tt.latest, got, tt.want)
			}
		})
	}
}

func TestLatest(t *testing.T) {
	tests := []struct {
		name    string
		status  int
		body    string
		wantTag string
		wantErr bool
	}{
		{"ok", 200, `{"tag_name":"v1.2.3","html_url":"https://x/r","assets":[{"name":"a.exe","browser_download_url":"https://x/a.exe"}]}`, "v1.2.3", false},
		{"not found", 404, `{}`, "", true},
		{"bad json", 200, `{`, "", true},
		{"missing tag", 200, `{"html_url":"u"}`, "", true},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				w.WriteHeader(tt.status)
				_, _ = w.Write([]byte(tt.body))
			}))
			defer srv.Close()

			rel, err := Latest(context.Background(), nil, srv.URL)
			if (err != nil) != tt.wantErr {
				t.Fatalf("err = %v, wantErr %v", err, tt.wantErr)
			}
			if err == nil {
				if rel.Tag != tt.wantTag {
					t.Errorf("tag = %q", rel.Tag)
				}
				if a, ok := rel.FindAsset("a.exe"); !ok || a.URL != "https://x/a.exe" {
					t.Errorf("asset = %+v %v", a, ok)
				}
				if _, ok := rel.FindAsset("missing"); ok {
					t.Error("unexpected asset")
				}
			}
		})
	}
}

func TestLatestUnreachable(t *testing.T) {
	srv := httptest.NewServer(http.NotFoundHandler())
	url := srv.URL
	srv.Close()
	if _, err := Latest(context.Background(), nil, url); err == nil {
		t.Error("expected error for unreachable server")
	}
}

func TestLatestBadURL(t *testing.T) {
	if _, err := Latest(context.Background(), nil, "://bad"); err == nil {
		t.Error("expected error for bad URL")
	}
}