// scan_test.go — 以假 client 驗證 Scanner 的命令層語義（對照 gitea.py）：
// next 三層拾取與「最久未更新優先」、mine/pulls 過濾、members --has-work。
package workflow

import (
	"errors"
	"fmt"
	"reflect"
	"testing"
)

// fakeClient 以記憶體資料實作 Client。
type fakeClient struct {
	currentUser string
	orgs        []Org
	teams       map[string][]Team        // org → teams
	teamMembers map[int64][]string       // teamID → 帳號
	repos       map[string][]Repo        // org → repos
	issues      map[string][]Issue       // "owner/repo" → issues（open，不含 PR）
	pulls       map[string][]PullRequest // "owner/repo" → open PR
	comments    map[string][]Comment     // "owner/repo#number" → 留言
	failOn      map[string]error         // 端點 → 錯誤（測失敗傳播）
}

func (f *fakeClient) CurrentUser() (string, error) {
	if err := f.failOn["user"]; err != nil {
		return "", err
	}
	return f.currentUser, nil
}

func (f *fakeClient) ListOrgs() ([]string, error) {
	if err := f.failOn["orgs"]; err != nil {
		return nil, err
	}
	out := make([]string, 0, len(f.orgs))
	for _, o := range f.orgs {
		out = append(out, o.Account())
	}
	return out, nil
}

func (f *fakeClient) ListTeams(org string) ([]Team, error) {
	if err := f.failOn["teams"]; err != nil {
		return nil, err
	}
	return f.teams[org], nil
}

func (f *fakeClient) ListTeamMembers(teamID int64) ([]string, error) {
	if err := f.failOn["members"]; err != nil {
		return nil, err
	}
	return f.teamMembers[teamID], nil
}

func (f *fakeClient) ListOrgRepos(org string) ([]Repo, error) {
	if err := f.failOn["repos"]; err != nil {
		return nil, err
	}
	return f.repos[org], nil
}

func (f *fakeClient) ListIssues(owner, repo string) ([]Issue, error) {
	if err := f.failOn["issues"]; err != nil {
		return nil, err
	}
	return f.issues[owner+"/"+repo], nil
}

func (f *fakeClient) ListPulls(owner, repo string) ([]PullRequest, error) {
	if err := f.failOn["pulls"]; err != nil {
		return nil, err
	}
	return f.pulls[owner+"/"+repo], nil
}

func (f *fakeClient) ListComments(owner, repo string, number int64) ([]Comment, error) {
	if err := f.failOn["comments"]; err != nil {
		return nil, err
	}
	return f.comments[fmt.Sprintf("%s/%s#%d", owner, repo, number)], nil
}

// newTestScanner 構造測試情境：一個組織、一個 Agents 團隊、兩個倉庫。
func newTestScanner() (*Scanner, *fakeClient) {
	fc := &fakeClient{
		currentUser: "alex",
		orgs:        []Org{{UserName: "alterminal"}},
		teams:       map[string][]Team{"alterminal": {{ID: 1, Name: "Agents"}}},
		teamMembers: map[int64][]string{1: {"alex", "max", "queena"}},
		repos:       map[string][]Repo{"alterminal": {{Name: "teai"}, {Name: "agents"}}},
		issues:      map[string][]Issue{},
		pulls:       map[string][]PullRequest{},
		comments:    map[string][]Comment{},
		failOn:      map[string]error{},
	}
	return &Scanner{Client: fc}, fc
}

func TestNextLayerPriority(t *testing.T) {
	s, fc := newTestScanner()
	// 三層各有工作：author PR、reviewer PR、issue。
	fc.pulls["alterminal/teai"] = []PullRequest{
		{
			Number: 10, Title: "我的 PR", UpdatedAt: "2026-09-09T00:00:00Z",
			User: mkUser("alex"),
		},
		{
			Number: 11, Title: "待我審核的 PR", UpdatedAt: "2026-09-09T01:00:00Z",
			User:               mkUser("max"),
			RequestedReviewers: []User{*mkUser("alex")},
		},
	}
	// author PR #10 有他人留言 → 需跟進。
	fc.comments["alterminal/teai#10"] = []Comment{
		{CreatedAt: "2026-09-09T00:10:00Z", User: mkUser("ceo")},
	}
	// reviewer PR #11 尚無留言 → 審核者仍應被列入。
	fc.issues["alterminal/agents"] = []Issue{
		{Number: 30, Title: "分派給 alex", UpdatedAt: "2026-09-08T00:00:00Z", Assignees: []User{*mkUser("alex")}},
	}
	work, err := s.Next()
	if err != nil {
		t.Fatal(err)
	}
	if work.Type != "pull" || work.Role != "author" || work.Number != 10 {
		t.Errorf("第一層應選 author PR #10，得到 %+v", work)
	}
}

func TestNextLayerFallbackToReviewer(t *testing.T) {
	s, fc := newTestScanner()
	fc.pulls["alterminal/teai"] = []PullRequest{
		{
			Number: 11, Title: "待審核", UpdatedAt: "2026-09-09T01:00:00Z",
			User:               mkUser("max"),
			RequestedReviewers: []User{*mkUser("alex")},
		},
	}
	fc.issues["alterminal/agents"] = []Issue{
		{Number: 30, Title: "分派給 alex", UpdatedAt: "2026-09-08T00:00:00Z", Assignees: []User{*mkUser("alex")}},
	}
	work, err := s.Next()
	if err != nil {
		t.Fatal(err)
	}
	if work.Type != "pull" || work.Role != "reviewer" || work.Number != 11 {
		t.Errorf("第二層應選 reviewer PR #11，得到 %+v", work)
	}
}

func TestNextLayerFallbackToIssue(t *testing.T) {
	s, fc := newTestScanner()
	fc.issues["alterminal/agents"] = []Issue{
		{Number: 30, Title: "分派給 alex", UpdatedAt: "2026-09-08T00:00:00Z", Assignees: []User{*mkUser("alex")}},
	}
	work, err := s.Next()
	if err != nil {
		t.Fatal(err)
	}
	if work.Type != "issue" || work.Number != 30 {
		t.Errorf("第三層應選 issue #30，得到 %+v", work)
	}
}

// TestNextPicksIssueInEmptyRepo 回歸測試（#43）：空倉庫（empty=true）中
// 分派給目前帳號的 open issue 應被第三層拾取——gitea.py 的
// for_all_repositories 掃 issue 不跳過空倉庫（「初始化項目」型工作）。
func TestNextPicksIssueInEmptyRepo(t *testing.T) {
	s, fc := newTestScanner()
	fc.repos["alterminal"] = []Repo{
		{Name: "teai"},
		{Name: "colony-tick-demo", Empty: true},
	}
	fc.issues["alterminal/colony-tick-demo"] = []Issue{
		{
			Number: 1, Title: "初始化項目", UpdatedAt: "2026-09-08T00:00:00Z",
			Assignees:  []User{*mkUser("alex")},
			Repository: &Repository{FullName: "alterminal/colony-tick-demo"},
			HTMLURL:    "https://gitea.alterminal.com/alterminal/colony-tick-demo/issues/1",
		},
	}
	work, err := s.Next()
	if err != nil {
		t.Fatal(err)
	}
	if work == nil || work.Type != "issue" || work.Number != 1 || work.Repo != "alterminal/colony-tick-demo" {
		t.Errorf("應拾取空倉庫中的 issue #1，得到 %+v", work)
	}
}

// TestMineIncludesEmptyRepoIssues 回歸測試（#43）：mine 同樣不因倉庫為空而漏列。
func TestMineIncludesEmptyRepoIssues(t *testing.T) {
	s, fc := newTestScanner()
	fc.repos["alterminal"] = []Repo{
		{Name: "teai"},
		{Name: "colony-tick-demo", Empty: true},
	}
	fc.issues["alterminal/colony-tick-demo"] = []Issue{
		{Number: 1, Title: "初始化項目", UpdatedAt: "2026-09-08T00:00:00Z", Assignees: []User{*mkUser("alex")}},
	}
	issues, err := s.Mine()
	if err != nil {
		t.Fatal(err)
	}
	if len(issues) != 1 || issues[0].Num() != 1 {
		t.Errorf("mine 應列出空倉庫中的 issue #1，得到 %d 件", len(issues))
	}
}

func TestNextNone(t *testing.T) {
	s, _ := newTestScanner()
	work, err := s.Next()
	if err != nil {
		t.Fatal(err)
	}
	if work != nil {
		t.Errorf("無工作應回 nil，得到 %+v", work)
	}
}

func TestNextOldestFirst(t *testing.T) {
	s, fc := newTestScanner()
	fc.issues["alterminal/agents"] = []Issue{
		{Number: 31, Title: "較新", UpdatedAt: "2026-09-09T00:00:00Z", Assignees: []User{*mkUser("alex")}},
		{Number: 30, Title: "較舊", UpdatedAt: "2026-09-08T00:00:00Z", Assignees: []User{*mkUser("alex")}},
	}
	work, err := s.Next()
	if err != nil {
		t.Fatal(err)
	}
	if work.Number != 30 {
		t.Errorf("應選最久未更新的 #30，得到 %+v", work)
	}
}

func TestMineSkipsLastCommentByAssignee(t *testing.T) {
	s, fc := newTestScanner()
	fc.issues["alterminal/agents"] = []Issue{
		{Number: 30, Title: "已在處理", UpdatedAt: "a", Assignees: []User{*mkUser("alex")}},
	}
	fc.comments["alterminal/agents#30"] = []Comment{
		{CreatedAt: "b", User: mkUser("alex")},
	}
	issues, err := s.Mine()
	if err != nil {
		t.Fatal(err)
	}
	if len(issues) != 0 {
		t.Errorf("最後留言來自 assignee → 應略過，得到 %d 件", len(issues))
	}
}

func TestPullsMineReviewersExclusive(t *testing.T) {
	s, _ := newTestScanner()
	if _, err := s.Pulls(true, true); !errors.Is(err, errIncompatibleFlags) {
		t.Errorf("--mine 與 --reviewer 併用應回 errIncompatibleFlags，得到 %v", err)
	}
}

func TestMembersHasWork(t *testing.T) {
	s, fc := newTestScanner()
	// alex 有待審核 PR；max 無任何工作；queena 有分派 issue。
	fc.pulls["alterminal/teai"] = []PullRequest{
		{
			Number: 11, UpdatedAt: "a", User: mkUser("max"),
			RequestedReviewers: []User{*mkUser("alex")},
		},
	}
	fc.issues["alterminal/agents"] = []Issue{
		{Number: 30, UpdatedAt: "b", Assignees: []User{*mkUser("queena")}},
	}
	got, err := s.Members(true)
	if err != nil {
		t.Fatal(err)
	}
	if !reflect.DeepEqual(got, []string{"alex", "queena"}) {
		t.Errorf("應只有 alex 與 queena 有工作，得到 %v", got)
	}
}

func TestErrorPropagation(t *testing.T) {
	s, fc := newTestScanner()
	fc.failOn["orgs"] = errors.New("boom")
	if _, err := s.Next(); err == nil {
		t.Errorf("API 錯誤應向上傳播，不應吞掉")
	}
}

func TestRoleWorker(t *testing.T) {
	s, _ := newTestScanner()
	got, err := s.Role()
	if err != nil {
		t.Fatal(err)
	}
	if got != RoleWorker {
		t.Errorf("Agents 團隊成員應為 worker，得到 %q", got)
	}
}

func TestRoleSupervisor(t *testing.T) {
	s, fc := newTestScanner()
	fc.teams["alterminal"] = []Team{
		{ID: 1, Name: "Agents"},
		{ID: 2, Name: "Supervisor"},
	}
	fc.teamMembers[2] = []string{"alex"}
	got, err := s.Role()
	if err != nil {
		t.Fatal(err)
	}
	if got != RoleSupervisor {
		t.Errorf("Supervisor 團隊成員應為 supervisor，得到 %q", got)
	}
}

func TestRoleSupervisorTakesPrecedence(t *testing.T) {
	s, fc := newTestScanner()
	// alex 同時在 Agents（newTestScanner 預設）與 Supervisor。
	fc.teams["alterminal"] = []Team{
		{ID: 1, Name: "Agents"},
		{ID: 2, Name: "Supervisor"},
	}
	fc.teamMembers[2] = []string{"alex", "ceo"}
	got, err := s.Role()
	if err != nil {
		t.Fatal(err)
	}
	if got != RoleSupervisor {
		t.Errorf("同時屬於兩者時應為 supervisor，得到 %q", got)
	}
}

func TestRoleNone(t *testing.T) {
	s, fc := newTestScanner()
	fc.currentUser = "outsider"
	got, err := s.Role()
	if err != nil {
		t.Fatal(err)
	}
	if got != "" {
		t.Errorf("不在 Supervisor／Agents 應回空字串，得到 %q", got)
	}
}

func TestRoleWorkerWhenSupervisorExists(t *testing.T) {
	s, fc := newTestScanner()
	fc.teams["alterminal"] = []Team{
		{ID: 1, Name: "Agents"},
		{ID: 2, Name: "Supervisor"},
	}
	fc.teamMembers[2] = []string{"ceo"}
	got, err := s.Role()
	if err != nil {
		t.Fatal(err)
	}
	if got != RoleWorker {
		t.Errorf("只在 Agents、不在 Supervisor 應為 worker，得到 %q", got)
	}
}

func TestRoleErrorPropagation(t *testing.T) {
	s, fc := newTestScanner()
	fc.failOn["teams"] = errors.New("boom")
	if _, err := s.Role(); err == nil {
		t.Errorf("ListTeams 錯誤應向上傳播")
	}
	delete(fc.failOn, "teams")
	fc.failOn["members"] = errors.New("boom")
	if _, err := s.Role(); err == nil {
		t.Errorf("ListTeamMembers 錯誤應向上傳播")
	}
}

func TestPullsDefault(t *testing.T) {
	s, fc := newTestScanner()
	fc.pulls["alterminal/teai"] = []PullRequest{
		{Number: 10, UpdatedAt: "a", User: mkUser("alex")},
	}
	fc.comments["alterminal/teai#10"] = []Comment{
		{CreatedAt: "b", User: mkUser("ceo")},
	}
	items, err := s.Pulls(false, false)
	if err != nil {
		t.Fatal(err)
	}
	if len(items) != 1 || items[0].Repo != "teai" {
		t.Errorf("應列出待跟進 PR，得到 %+v", items)
	}
}