package httpapi

import (
	"context"
	"encoding/json"
	"fmt"
	"net/http"
	"strings"
	"time"

	"spin/internal/mailsync"
	"spin/internal/models"

	"github.com/go-chi/chi/v5"
	"gorm.io/datatypes"
)

// ---- company / product / version (master data) ----------------------------

func (s *Server) handleListCompanies(w http.ResponseWriter, r *http.Request) {
	var out []models.Company
	s.db.Order("name asc").Find(&out)
	writeJSON(w, http.StatusOK, out)
}

func (s *Server) handleCreateCompany(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var c models.Company
	if err := decodeJSON(r, &c); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	s.db.Create(&c)
	writeJSON(w, http.StatusCreated, c)
}

func (s *Server) handleListProducts(w http.ResponseWriter, r *http.Request) {
	q := s.db.Order("name asc")
	if cid := r.URL.Query().Get("companyId"); cid != "" {
		q = q.Where("company_id = ?", cid)
	}
	var out []models.Product
	q.Find(&out)
	writeJSON(w, http.StatusOK, out)
}

func (s *Server) handleCreateProduct(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var p models.Product
	if err := decodeJSON(r, &p); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	s.db.Create(&p)
	writeJSON(w, http.StatusCreated, p)
}

func (s *Server) handleListVersions(w http.ResponseWriter, r *http.Request) {
	q := s.db.Order("label asc")
	if pid := r.URL.Query().Get("productId"); pid != "" {
		q = q.Where("product_id = ?", pid)
	}
	var out []models.Version
	q.Find(&out)
	writeJSON(w, http.StatusOK, out)
}

func (s *Server) handleCreateVersion(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var v models.Version
	if err := decodeJSON(r, &v); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	s.db.Create(&v)
	writeJSON(w, http.StatusCreated, v)
}

// patchByID applies a whitelisted-free JSON patch to a model row (admin only).
func (s *Server) patchModel(w http.ResponseWriter, r *http.Request, dest interface{}, id string) {
	if !s.requireAdmin(w, r) {
		return
	}
	if err := s.db.First(dest, "id = ?", id).Error; err != nil {
		writeError(w, http.StatusNotFound, "찾을 수 없습니다")
		return
	}
	var patch map[string]interface{}
	if err := decodeJSON(r, &patch); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	delete(patch, "id")
	if err := s.db.Model(dest).Updates(patch).Error; err != nil {
		writeError(w, http.StatusInternalServerError, err.Error())
		return
	}
	s.db.First(dest, "id = ?", id)
	writeJSON(w, http.StatusOK, dest)
}

func (s *Server) handlePatchCompany(w http.ResponseWriter, r *http.Request) {
	s.patchModel(w, r, &models.Company{}, chi.URLParam(r, "id"))
}
func (s *Server) handleDeleteCompany(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	s.db.Delete(&models.Company{}, "id = ?", chi.URLParam(r, "id"))
	writeJSON(w, http.StatusOK, map[string]bool{"ok": true})
}
func (s *Server) handlePatchProduct(w http.ResponseWriter, r *http.Request) {
	s.patchModel(w, r, &models.Product{}, chi.URLParam(r, "id"))
}
func (s *Server) handleDeleteProduct(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	s.db.Delete(&models.Product{}, "id = ?", chi.URLParam(r, "id"))
	writeJSON(w, http.StatusOK, map[string]bool{"ok": true})
}
func (s *Server) handlePatchVersion(w http.ResponseWriter, r *http.Request) {
	s.patchModel(w, r, &models.Version{}, chi.URLParam(r, "id"))
}
func (s *Server) handleDeleteVersion(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	s.db.Delete(&models.Version{}, "id = ?", chi.URLParam(r, "id"))
	writeJSON(w, http.StatusOK, map[string]bool{"ok": true})
}

// ---- projects -------------------------------------------------------------

// myProjectIDs returns the project IDs the caller is a member of (or PM of).
func (s *Server) myProjectIDs(email string) []string {
	var ids []string
	s.db.Model(&models.ProjectMember{}).Where("lower(member_email) = ?", lc(email)).
		Distinct().Pluck("project_id", &ids)
	var pmIDs []string
	s.db.Model(&models.Project{}).Where("lower(pm_email) = ?", lc(email)).Pluck("id", &pmIDs)
	return append(ids, pmIDs...)
}

func (s *Server) handleListProjects(w http.ResponseWriter, r *http.Request) {
	q := s.db.Order("created_at desc")
	// Non-admins always see only their own projects. Admins see all by default,
	// but the "나의 업무" view passes ?scope=mine to get the same own-only list.
	if !s.isAdmin(r) || r.URL.Query().Get("scope") == "mine" {
		ids := s.myProjectIDs(s.email(r))
		if len(ids) == 0 {
			writeJSON(w, http.StatusOK, []models.Project{})
			return
		}
		q = q.Where("id IN ?", ids)
	}
	if cid := r.URL.Query().Get("companyId"); cid != "" {
		q = q.Where("company_id = ?", cid)
	}
	if st := r.URL.Query().Get("status"); st != "" {
		q = q.Where("status = ?", st)
	}
	var out []models.Project
	q.Find(&out)
	writeJSON(w, http.StatusOK, out)
}

// canSeeProject reports whether the caller may view a project (admin or member).
func (s *Server) canSeeProject(r *http.Request, projectID string) bool {
	if s.isAdmin(r) {
		return true
	}
	for _, id := range s.myProjectIDs(s.email(r)) {
		if id == projectID {
			return true
		}
	}
	return false
}

func (s *Server) handleGetProject(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if !s.canSeeProject(r, id) {
		writeError(w, http.StatusForbidden, "참여한 프로젝트만 조회할 수 있습니다")
		return
	}
	var p models.Project
	if err := s.db.First(&p, "id = ?", id).Error; err != nil {
		writeError(w, http.StatusNotFound, "프로젝트를 찾을 수 없습니다")
		return
	}
	writeJSON(w, http.StatusOK, p)
}

func (s *Server) handleCreateProject(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var p models.Project
	if err := decodeJSON(r, &p); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	if p.Status == "" {
		p.Status = "planned"
	}
	s.db.Create(&p)
	s.audit(r, "create", "project", p.ID, p.Name)
	if p.PMEmail != "" && !s.owns(r, p.PMEmail) {
		s.notify(p.PMEmail, "project", "프로젝트 PM으로 지정되었습니다", p.Name, "/projects/"+p.ID)
	}
	writeJSON(w, http.StatusCreated, p)
}

func (s *Server) handlePatchProject(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var p models.Project
	if err := s.db.First(&p, "id = ?", chi.URLParam(r, "id")).Error; err != nil {
		writeError(w, http.StatusNotFound, "프로젝트를 찾을 수 없습니다")
		return
	}
	oldPM := p.PMEmail
	var patch map[string]interface{}
	if err := decodeJSON(r, &patch); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	delete(patch, "id")
	// JSON 키(camelCase)를 DB 컬럼(snake_case)으로 변환해야 멀티워드 필드
	// (consultingType·scopeText·pmEmail·clientDomain·startDate 등)가 저장된다.
	patch = snakeKeys(patch)
	if err := s.db.Model(&p).Updates(patch).Error; err != nil {
		writeError(w, http.StatusInternalServerError, err.Error())
		return
	}
	s.db.First(&p, "id = ?", p.ID)
	if p.PMEmail != "" && !strings.EqualFold(p.PMEmail, oldPM) && !s.owns(r, p.PMEmail) {
		s.notify(p.PMEmail, "project", "프로젝트 PM으로 지정되었습니다", p.Name, "/projects/"+p.ID)
	}
	writeJSON(w, http.StatusOK, p)
}

// snakeKeys converts camelCase JSON map keys to snake_case DB column names so
// GORM Updates(map) targets the right columns. Safe for camelCase keys (no
// leading/consecutive capitals), which is how all our JSON tags are written.
func snakeKeys(m map[string]interface{}) map[string]interface{} {
	out := make(map[string]interface{}, len(m))
	for k, v := range m {
		var b strings.Builder
		for i, r := range k {
			if r >= 'A' && r <= 'Z' {
				if i > 0 {
					b.WriteByte('_')
				}
				b.WriteRune(r - 'A' + 'a')
			} else {
				b.WriteRune(r)
			}
		}
		out[b.String()] = v
	}
	return out
}

func (s *Server) handleDeleteProject(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	s.db.Delete(&models.Project{}, "id = ?", chi.URLParam(r, "id"))
	writeJSON(w, http.StatusOK, map[string]bool{"ok": true})
}

// ---- project members (portion) -------------------------------------------

func (s *Server) handleListProjectMembers(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if !s.canSeeProject(r, id) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	var out []models.ProjectMember
	s.db.Where("project_id = ?", id).Find(&out)
	writeJSON(w, http.StatusOK, out)
}

func (s *Server) handleUpsertProjectMember(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var pm models.ProjectMember
	if err := decodeJSON(r, &pm); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	pm.ProjectID = chi.URLParam(r, "id")
	if pm.ID != "" {
		s.db.Save(&pm)
	} else {
		s.db.Create(&pm)
		var proj models.Project
		s.db.First(&proj, "id = ?", pm.ProjectID)
		s.notify(pm.MemberEmail, "project", "프로젝트에 추가되었습니다",
			fmt.Sprintf("'%s' 프로젝트에 작업자로 추가되었습니다. (기여도 %g%%)", proj.Name, pm.Portion),
			"/projects/"+pm.ProjectID)
	}
	writeJSON(w, http.StatusOK, pm)
}

func (s *Server) handleDeleteProjectMember(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	s.db.Delete(&models.ProjectMember{}, "id = ?", chi.URLParam(r, "pmId"))
	writeJSON(w, http.StatusOK, map[string]bool{"ok": true})
}

// ---- client contacts ------------------------------------------------------

func (s *Server) handleListContacts(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if !s.canSeeProject(r, id) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	var out []models.ClientContact
	s.db.Where("project_id = ?", id).Find(&out)
	writeJSON(w, http.StatusOK, out)
}

func (s *Server) handleUpsertContact(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var c models.ClientContact
	if err := decodeJSON(r, &c); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	c.ProjectID = chi.URLParam(r, "id")
	if c.ID != "" {
		s.db.Save(&c)
	} else {
		s.db.Create(&c)
	}
	writeJSON(w, http.StatusOK, c)
}

func (s *Server) handleDeleteContact(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	s.db.Delete(&models.ClientContact{}, "id = ?", chi.URLParam(r, "cId"))
	writeJSON(w, http.StatusOK, map[string]bool{"ok": true})
}

// ---- tasks (gantt / kanban) ----------------------------------------------

func (s *Server) handleListTasks(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if !s.canSeeProject(r, id) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	var out []models.ProjectTask
	s.db.Where("project_id = ?", id).Order("order_idx asc, start asc").Find(&out)
	writeJSON(w, http.StatusOK, out)
}

func (s *Server) handleCreateTask(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if !s.canSeeProject(r, id) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	var t models.ProjectTask
	if err := decodeJSON(r, &t); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	t.ProjectID = id
	if t.Lane == "" {
		t.Lane = "todo"
	}
	s.db.Create(&t)
	// 담당자로 배정되면 본인에게 알림(+모바일 푸시). 본인이 본인에게 단 경우는 제외.
	if t.Assignee != "" && !s.owns(r, t.Assignee) {
		s.notify(t.Assignee, "task", "작업에 배정되었습니다",
			fmt.Sprintf("[%s] %s", s.projectName(id), t.Title), "/projects/"+id)
	}
	writeJSON(w, http.StatusCreated, t)
}

// projectName returns a project's name (best-effort) for notification text.
func (s *Server) projectName(id string) string {
	var p models.Project
	s.db.Select("name").First(&p, "id = ?", id)
	return p.Name
}

func (s *Server) handlePatchTask(w http.ResponseWriter, r *http.Request) {
	var t models.ProjectTask
	if err := s.db.First(&t, "id = ?", chi.URLParam(r, "tId")).Error; err != nil {
		writeError(w, http.StatusNotFound, "작업을 찾을 수 없습니다")
		return
	}
	if !s.canSeeProject(r, t.ProjectID) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	oldAssignee := t.Assignee
	var patch map[string]interface{}
	if err := decodeJSON(r, &patch); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	delete(patch, "id")
	delete(patch, "projectId")
	// JSON 슬라이스 컬럼(labels/dependsOn)은 map 패치 시 driver.Valuer로 변환해 줘야 한다.
	for _, k := range []string{"labels", "dependsOn"} {
		if v, ok := patch[k]; ok {
			if b, err := json.Marshal(v); err == nil {
				patch[k] = datatypes.JSON(b)
			}
		}
	}
	patch = snakeKeys(patch)
	s.db.Model(&t).Updates(patch)
	s.db.First(&t, "id = ?", t.ID)
	// 담당자가 새 사람으로 바뀌면 그 사람에게 알림(+푸시).
	if t.Assignee != "" && !strings.EqualFold(t.Assignee, oldAssignee) && !s.owns(r, t.Assignee) {
		s.notify(t.Assignee, "task", "작업에 배정되었습니다",
			fmt.Sprintf("[%s] %s", s.projectName(t.ProjectID), t.Title), "/projects/"+t.ProjectID)
	}
	writeJSON(w, http.StatusOK, t)
}

// ---- task comments (JIRA형 댓글) -----------------------------------------

func (s *Server) taskProjectID(taskID string) (string, bool) {
	var t models.ProjectTask
	if err := s.db.Select("project_id").First(&t, "id = ?", taskID).Error; err != nil {
		return "", false
	}
	return t.ProjectID, true
}

func (s *Server) handleListTaskComments(w http.ResponseWriter, r *http.Request) {
	tid := chi.URLParam(r, "tId")
	pid, ok := s.taskProjectID(tid)
	if !ok || !s.canSeeProject(r, pid) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	var out []models.TaskComment
	s.db.Where("task_id = ?", tid).Order("created_at asc").Find(&out)
	writeJSON(w, http.StatusOK, out)
}

func (s *Server) handleCreateTaskComment(w http.ResponseWriter, r *http.Request) {
	tid := chi.URLParam(r, "tId")
	pid, ok := s.taskProjectID(tid)
	if !ok || !s.canSeeProject(r, pid) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	var c models.TaskComment
	if err := decodeJSON(r, &c); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	if strings.TrimSpace(c.Body) == "" {
		writeError(w, http.StatusBadRequest, "내용을 입력하세요")
		return
	}
	c.ID = ""
	c.TaskID = tid
	c.AuthorEmail = s.email(r)
	s.db.Create(&c)
	// 댓글이 달리면 작업 담당자에게 알림(본인 댓글 제외).
	var t models.ProjectTask
	if s.db.Select("assignee", "title", "project_id").First(&t, "id = ?", tid).Error == nil {
		if t.Assignee != "" && !s.owns(r, t.Assignee) {
			body := c.Body
			if len(body) > 50 {
				body = body[:50] + "…"
			}
			s.notify(t.Assignee, "task", "내 작업에 새 댓글",
				fmt.Sprintf("%s — %s", t.Title, body), "/projects/"+t.ProjectID)
		}
	}
	writeJSON(w, http.StatusCreated, c)
}

func (s *Server) handleDeleteTaskComment(w http.ResponseWriter, r *http.Request) {
	var c models.TaskComment
	if err := s.db.First(&c, "id = ?", chi.URLParam(r, "cId")).Error; err != nil {
		writeError(w, http.StatusNotFound, "댓글을 찾을 수 없습니다")
		return
	}
	if !s.isAdmin(r) && !s.owns(r, c.AuthorEmail) {
		writeError(w, http.StatusForbidden, "본인 댓글만 삭제할 수 있습니다")
		return
	}
	s.db.Delete(&models.TaskComment{}, "id = ?", c.ID)
	writeJSON(w, http.StatusOK, map[string]bool{"ok": true})
}

// ---- project mail (Google Workspace 도메인 위임) + 공동 메모 -----------------

type mailItem struct {
	models.ProjectMailMsg
	Note         string `json:"note"`         // 공동 메모 본문
	NoteEditedBy string `json:"noteEditedBy"` // 메모 마지막 수정자
}

// handleListProjectMails returns the stored client-domain mail for the project,
// each with its shared memo, filtered to messages the requester is a party to
// (from/to/cc). Hidden flag travels along so the UI can collapse hidden items.
// A never-synced project triggers an async full backfill.
func (s *Server) handleListProjectMails(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if !s.canSeeProject(r, id) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	var p models.Project
	if err := s.db.First(&p, "id = ?", id).Error; err != nil {
		writeError(w, http.StatusNotFound, "프로젝트를 찾을 수 없습니다")
		return
	}
	resp := map[string]any{
		"enabled":  s.mail.Enabled(),
		"domain":   p.ClientDomain,
		"messages": []mailItem{},
	}
	if strings.TrimSpace(p.ClientDomain) == "" {
		writeJSON(w, http.StatusOK, resp)
		return
	}

	var st models.ProjectMailState
	synced := s.db.First(&st, "project_id = ?", id).Error == nil
	if synced && st.LastSyncedAt != nil {
		resp["lastSyncedAt"] = st.LastSyncedAt
	}
	if st.LastError != "" {
		resp["error"] = st.LastError
	}
	// First ever view → kick off full backfill in the background (only if mail
	// integration is configured). Already-stored mail is shown regardless.
	if !synced && s.mail.Enabled() {
		resp["syncing"] = true
		go syncProjectMail(context.Background(), s.db, s.mail, id, true)
	}

	var rows []models.ProjectMailMsg
	s.db.Where("project_id = ?", id).Order("ts desc").Find(&rows)
	notes := map[string]models.MailNote{}
	var nl []models.MailNote
	s.db.Where("project_id = ?", id).Find(&nl)
	for _, n := range nl {
		notes[n.MessageID] = n
	}
	me := s.email(r)
	items := make([]mailItem, 0, len(rows))
	for _, row := range rows {
		m := mailsync.Message{ID: row.MessageID, From: row.FromAddr, To: row.ToAddr, Cc: row.CcAddr}
		if !m.Involves(me) {
			continue
		}
		it := mailItem{ProjectMailMsg: row}
		if n, ok := notes[row.MessageID]; ok {
			it.Note = n.Body
			it.NoteEditedBy = n.LastEditedBy
		}
		items = append(items, it)
	}
	resp["messages"] = items
	writeJSON(w, http.StatusOK, resp)
}

// handleSyncProjectMail forces a full resync (async). Any project member may run it.
func (s *Server) handleSyncProjectMail(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if !s.canSeeProject(r, id) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	go syncProjectMail(context.Background(), s.db, s.mail, id, true)
	writeJSON(w, http.StatusAccepted, map[string]bool{"started": true})
}

// handleHideMail toggles project-level visibility of one mail (declutter). Any
// project member may hide/unhide; it applies for the whole project.
func (s *Server) handleHideMail(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if !s.canSeeProject(r, id) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	var in struct {
		MessageID string `json:"messageId"`
		Hidden    bool   `json:"hidden"`
	}
	if err := decodeJSON(r, &in); err != nil || strings.TrimSpace(in.MessageID) == "" {
		writeError(w, http.StatusBadRequest, "messageId가 필요합니다")
		return
	}
	by := ""
	if in.Hidden {
		by = s.email(r)
	}
	s.db.Model(&models.ProjectMailMsg{}).
		Where("project_id = ? AND message_id = ?", id, in.MessageID).
		Updates(map[string]interface{}{"hidden": in.Hidden, "hidden_by": by})
	writeJSON(w, http.StatusOK, map[string]bool{"ok": true})
}

func (s *Server) handleListMailNotes(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if !s.canSeeProject(r, id) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	var out []models.MailNote
	s.db.Where("project_id = ?", id).Find(&out)
	writeJSON(w, http.StatusOK, out)
}

// handlePutMailNote upserts the shared memo for one email. Any project member may
// edit it; the message id travels in the body (Message-ID contains <>@ chars).
func (s *Server) handlePutMailNote(w http.ResponseWriter, r *http.Request) {
	id := chi.URLParam(r, "id")
	if !s.canSeeProject(r, id) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	var in struct {
		MessageID string `json:"messageId"`
		Body      string `json:"body"`
	}
	if err := decodeJSON(r, &in); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	if strings.TrimSpace(in.MessageID) == "" {
		writeError(w, http.StatusBadRequest, "messageId가 필요합니다")
		return
	}
	var note models.MailNote
	err := s.db.Where("project_id = ? AND message_id = ?", id, in.MessageID).First(&note).Error
	note.Body = in.Body
	note.LastEditedBy = s.email(r)
	if err != nil { // not found → create
		note.ProjectID = id
		note.MessageID = in.MessageID
		s.db.Create(&note)
	} else {
		s.db.Model(&note).Updates(map[string]interface{}{"body": note.Body, "last_edited_by": note.LastEditedBy})
	}
	writeJSON(w, http.StatusOK, note)
}

func (s *Server) handleDeleteTask(w http.ResponseWriter, r *http.Request) {
	var t models.ProjectTask
	if err := s.db.First(&t, "id = ?", chi.URLParam(r, "tId")).Error; err != nil {
		writeError(w, http.StatusNotFound, "작업을 찾을 수 없습니다")
		return
	}
	if !s.isAdmin(r) && !s.canSeeProject(r, t.ProjectID) {
		writeError(w, http.StatusForbidden, "권한이 없습니다")
		return
	}
	s.db.Delete(&models.ProjectTask{}, "id = ?", t.ID)
	writeJSON(w, http.StatusOK, map[string]bool{"ok": true})
}

// ---- contract (ADMIN ONLY) ------------------------------------------------

func (s *Server) handleGetContract(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var c models.Contract
	if err := s.db.First(&c, "project_id = ?", chi.URLParam(r, "id")).Error; err != nil {
		writeJSON(w, http.StatusOK, nil) // no contract yet
		return
	}
	writeJSON(w, http.StatusOK, c)
}

func (s *Server) handlePutContract(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	pid := chi.URLParam(r, "id")
	var in models.Contract
	if err := decodeJSON(r, &in); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	in.ProjectID = pid
	var existing models.Contract
	if err := s.db.First(&existing, "project_id = ?", pid).Error; err == nil {
		in.ID = existing.ID
		s.db.Save(&in)
	} else {
		s.db.Create(&in)
	}
	s.audit(r, "update", "contract", pid, "")
	writeJSON(w, http.StatusOK, in)
}

// ---- contract files (ADMIN ONLY, S3) -------------------------------------

func (s *Server) handleListContractFiles(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var out []models.ContractFile
	s.db.Where("project_id = ?", chi.URLParam(r, "id")).Order("created_at desc").Find(&out)
	writeJSON(w, http.StatusOK, out)
}

func (s *Server) handleUploadContractFile(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	pid := chi.URLParam(r, "id")
	if err := r.ParseMultipartForm(50 << 20); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	file, hdr, err := r.FormFile("file")
	if err != nil {
		writeError(w, http.StatusBadRequest, "file 필드가 필요합니다")
		return
	}
	defer file.Close()
	kind := r.FormValue("kind")
	if kind == "" {
		kind = "contract"
	}
	key := fmt.Sprintf("contracts/%s/%d-%s", pid, time.Now().UnixNano(), hdr.Filename)
	if s.store != nil {
		if err := s.store.Upload(r.Context(), key, hdr.Header.Get("Content-Type"), file, hdr.Size); err != nil {
			writeError(w, http.StatusInternalServerError, "업로드 실패: "+err.Error())
			return
		}
	}
	cf := models.ContractFile{ProjectID: pid, Kind: kind, Filename: hdr.Filename, S3Key: key,
		Size: hdr.Size, UploadedBy: currentUser(r.Context()).Email}
	s.db.Create(&cf)
	s.audit(r, "upload", "contract_file", cf.ID, hdr.Filename)
	writeJSON(w, http.StatusCreated, cf)
}

func (s *Server) handleDownloadContractFile(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var cf models.ContractFile
	if err := s.db.First(&cf, "id = ?", chi.URLParam(r, "fId")).Error; err != nil {
		writeError(w, http.StatusNotFound, "파일을 찾을 수 없습니다")
		return
	}
	if s.store == nil {
		writeError(w, http.StatusServiceUnavailable, "스토리지가 비활성화되어 있습니다")
		return
	}
	url, err := s.store.PresignGet(r.Context(), cf.S3Key)
	if err != nil {
		writeError(w, http.StatusInternalServerError, err.Error())
		return
	}
	writeJSON(w, http.StatusOK, map[string]string{"url": url})
}

func (s *Server) handleDeleteContractFile(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var cf models.ContractFile
	if err := s.db.First(&cf, "id = ?", chi.URLParam(r, "fId")).Error; err != nil {
		writeError(w, http.StatusNotFound, "파일을 찾을 수 없습니다")
		return
	}
	if s.store != nil {
		_ = s.store.Delete(r.Context(), cf.S3Key)
	}
	s.db.Delete(&models.ContractFile{}, "id = ?", cf.ID)
	writeJSON(w, http.StatusOK, map[string]bool{"ok": true})
}

// ---- payment splits (ADMIN ONLY) -----------------------------------------

func (s *Server) handleListPayments(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var out []models.PaymentSplit
	s.db.Where("project_id = ?", chi.URLParam(r, "id")).Order("order_idx asc, expected_date asc").Find(&out)
	writeJSON(w, http.StatusOK, out)
}

func (s *Server) handleCreatePayment(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var p models.PaymentSplit
	if err := decodeJSON(r, &p); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	p.ProjectID = chi.URLParam(r, "id")
	s.db.Create(&p)
	writeJSON(w, http.StatusCreated, p)
}

func (s *Server) handlePatchPayment(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	var p models.PaymentSplit
	if err := s.db.First(&p, "id = ?", chi.URLParam(r, "payId")).Error; err != nil {
		writeError(w, http.StatusNotFound, "분할 항목을 찾을 수 없습니다")
		return
	}
	var patch map[string]interface{}
	if err := decodeJSON(r, &patch); err != nil {
		writeError(w, http.StatusBadRequest, err.Error())
		return
	}
	delete(patch, "id")
	delete(patch, "projectId")
	s.db.Model(&p).Updates(patch)
	s.db.First(&p, "id = ?", p.ID)
	writeJSON(w, http.StatusOK, p)
}

func (s *Server) handleDeletePayment(w http.ResponseWriter, r *http.Request) {
	if !s.requireAdmin(w, r) {
		return
	}
	s.db.Delete(&models.PaymentSplit{}, "id = ?", chi.URLParam(r, "payId"))
	writeJSON(w, http.StatusOK, map[string]bool{"ok": true})
}

// guard against unused import when trimming
var _ = strings.TrimSpace