package httpapi

import (
	"encoding/json"
	"net/http/httptest"
	"os"
	"path/filepath"
	"testing"

	"github.com/go-chi/chi/v5"
)

// buildVersionRouter mounts VersionHandler on a real chi router (mirrors how
// main.go mounts GET /version) so routing behaves exactly as in production.
func buildVersionRouter(path string) chi.Router {
	h := NewVersionHandler(path)
	r := chi.NewRouter()
	r.Get("/version", h.Serve)
	return r
}

func TestVersionHandler_ServesManifestFromDisk(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "version.yaml")
	yamlContent := `version: "1.2.3"
build_number: 10203
force_update: true
release_notes: "测试发布说明"
download_urls:
  android: "https://api.yanmeiai.com/downloads/pangolin-android.apk"
  windows: "https://api.yanmeiai.com/downloads/pangolin-windows-x64-setup.exe"
  macos: ""
  ios: ""
changelog:
  - version: "1.2.3"
    date: "2026-07-06"
    intro: "小版本更新"
    sections:
      - type: "新增"
        items:
          - "示例条目"
`
	if err := os.WriteFile(path, []byte(yamlContent), 0o644); err != nil {
		t.Fatalf("write fixture: %v", err)
	}

	r := buildVersionRouter(path)
	req := httptest.NewRequest("GET", "/version", nil)
	rec := httptest.NewRecorder()
	r.ServeHTTP(rec, req)

	if rec.Code != 200 {
		t.Fatalf("status = %d, want 200; body=%s", rec.Code, rec.Body.String())
	}

	var got versionManifest
	if err := json.Unmarshal(rec.Body.Bytes(), &got); err != nil {
		t.Fatalf("unmarshal response: %v; body=%s", err, rec.Body.String())
	}

	if got.Version != "1.2.3" {
		t.Errorf("version = %q, want %q", got.Version, "1.2.3")
	}
	if got.BuildNumber != 10203 {
		t.Errorf("build_number = %d, want %d", got.BuildNumber, 10203)
	}
	if !got.ForceUpdate {
		t.Errorf("force_update = false, want true")
	}
	if got.ReleaseNotes != "测试发布说明" {
		t.Errorf("release_notes = %q, want %q", got.ReleaseNotes, "测试发布说明")
	}
	if got.DownloadURLs["android"] != "https://api.yanmeiai.com/downloads/pangolin-android.apk" {
		t.Errorf("download_urls.android = %q", got.DownloadURLs["android"])
	}
	if got.DownloadURLs["windows"] != "https://api.yanmeiai.com/downloads/pangolin-windows-x64-setup.exe" {
		t.Errorf("download_urls.windows = %q", got.DownloadURLs["windows"])
	}
	if got.DownloadURLs["macos"] != "" || got.DownloadURLs["ios"] != "" {
		t.Errorf("expected empty macos/ios download URLs, got macos=%q ios=%q", got.DownloadURLs["macos"], got.DownloadURLs["ios"])
	}
	if len(got.Changelog) != 1 || got.Changelog[0].Version != "1.2.3" {
		t.Errorf("changelog = %+v, want 1 entry for version 1.2.3", got.Changelog)
	}
}

func TestVersionHandler_MissingFileReturnsDefault(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "does-not-exist.yaml")

	r := buildVersionRouter(path)
	req := httptest.NewRequest("GET", "/version", nil)
	rec := httptest.NewRecorder()
	r.ServeHTTP(rec, req)

	if rec.Code != 200 {
		t.Fatalf("status = %d, want 200 (missing file falls back to default manifest); body=%s", rec.Code, rec.Body.String())
	}

	var got versionManifest
	if err := json.Unmarshal(rec.Body.Bytes(), &got); err != nil {
		t.Fatalf("unmarshal response: %v; body=%s", err, rec.Body.String())
	}
	if got.Version == "" {
		t.Errorf("default manifest: version should not be empty")
	}
	if got.DownloadURLs["android"] == "" {
		t.Errorf("default manifest: download_urls.android should not be empty")
	}
	if got.DownloadURLs["windows"] == "" {
		t.Errorf("default manifest: download_urls.windows should not be empty")
	}
	if got.Changelog == nil {
		t.Errorf("default manifest: changelog should be [] not null")
	}
}

func TestVersionHandler_JSONShape(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "version.yaml")
	if err := os.WriteFile(path, []byte(`version: "1.0.0"
build_number: 10000
force_update: false
release_notes: ""
download_urls:
  android: "https://example.com/a.apk"
`), 0o644); err != nil {
		t.Fatalf("write fixture: %v", err)
	}

	r := buildVersionRouter(path)
	req := httptest.NewRequest("GET", "/version", nil)
	rec := httptest.NewRecorder()
	r.ServeHTTP(rec, req)

	var raw map[string]json.RawMessage
	if err := json.Unmarshal(rec.Body.Bytes(), &raw); err != nil {
		t.Fatalf("unmarshal raw response: %v", err)
	}
	for _, key := range []string{"version", "build_number", "force_update", "release_notes", "download_urls", "changelog"} {
		if _, ok := raw[key]; !ok {
			t.Errorf("response missing expected top-level key %q; body=%s", key, rec.Body.String())
		}
	}
	// changelog must serialize as an array even when the manifest omits it —
	// front-ends should be able to blindly .map()/range over it.
	if string(raw["changelog"]) != "[]" {
		t.Errorf("changelog = %s, want []", raw["changelog"])
	}
	if ct := rec.Header().Get("Content-Type"); ct != "application/json; charset=utf-8" {
		t.Errorf("Content-Type = %q, want application/json; charset=utf-8", ct)
	}
}

func TestVersionHandler_DefaultPathFallback(t *testing.T) {
	h := NewVersionHandler("")
	if h.path != defaultVersionManifestPath {
		t.Errorf("NewVersionHandler(\"\").path = %q, want %q", h.path, defaultVersionManifestPath)
	}
}