// The platform-admin drill-down: merchant -> shop -> camera.
//
// These exist because the tenant routes cannot serve this screen, and the
// reason is structural rather than incidental. Every tenant handler derives
// the client from the SESSION - that is what makes cross-tenant access
// impossible rather than merely disallowed - and a platform admin has no
// client at all. The three workarounds all make it worse: passing a company id
// to a tenant route puts a caller-chosen tenant back into the one place this
// system refuses to take one, filtering the whole estate in the browser ships
// every merchant's data to render one, and signing in as the owner leaves an
// audit trail naming the wrong person.
//
// So the tenant STORE functions are reused with an explicit client id and the
// scoping the tenant handlers get from the session is done here instead.
package api

import "net/http"

// clientForAdmin resolves {id} to a merchant that exists.
//
// A suspended merchant still resolves: "this company is suspended" is
// precisely what an admin opens the console to look at, and hiding it would
// make the one screen that can fix it the one screen that cannot see it.
func (s *Server) clientForAdmin(w http.ResponseWriter, r *http.Request) (ClientDetail, bool) {
	c, err := s.Store.ClientDetail(r.Context(), r.PathValue("id"))
	if err != nil {
		s.serverError(w, "admin client", err)
		return ClientDetail{}, false
	}
	if c.ID == "" {
		writeErr(w, http.StatusNotFound, "not_found", "No such merchant.")
		return ClientDetail{}, false
	}
	return c, true
}

// siteForAdmin resolves {site} within that merchant. A site belonging to
// somebody else is 404 and not an empty list: the caller asked for a named
// thing, and "here are its zero cameras" is a different and wrong answer.
func (s *Server) siteForAdmin(w http.ResponseWriter, r *http.Request, clientID string) (string, bool) {
	id, err := s.Store.AdminSiteID(r.Context(), clientID, r.PathValue("site"))
	if err != nil {
		s.serverError(w, "admin site", err)
		return "", false
	}
	if id == "" {
		writeErr(w, http.StatusNotFound, "not_found", "No such shop for this merchant.")
		return "", false
	}
	return id, true
}

func (s *Server) handleAdminClient(w http.ResponseWriter, r *http.Request) {
	c, ok := s.clientForAdmin(w, r)
	if !ok {
		return
	}
	writeJSON(w, http.StatusOK, c)
}

func (s *Server) handleAdminClientSites(w http.ResponseWriter, r *http.Request) {
	c, ok := s.clientForAdmin(w, r)
	if !ok {
		return
	}
	rows, err := s.Store.SiteHealth(r.Context(), c.ID)
	if err != nil {
		s.serverError(w, "admin sites", err)
		return
	}
	if rows == nil {
		rows = []SiteHealth{}
	}
	s.auditAdminRead(r, c.ID, "admin.sites.read", "client", c.ID, len(rows))
	writeJSON(w, http.StatusOK, rows)
}

func (s *Server) handleAdminClientSite(w http.ResponseWriter, r *http.Request) {
	c, ok := s.clientForAdmin(w, r)
	if !ok {
		return
	}
	siteID, ok := s.siteForAdmin(w, r, c.ID)
	if !ok {
		return
	}
	// SiteHealth is the one place that knows what "online" means (three missed
	// heartbeats, not one) and what cameras_up counts. A second query here
	// would be a second definition of a working shop, and the two would drift.
	rows, err := s.Store.SiteHealth(r.Context(), c.ID)
	if err != nil {
		s.serverError(w, "admin site", err)
		return
	}
	for _, row := range rows {
		if row.SiteID == siteID {
			s.auditAdminRead(r, c.ID, "admin.site.read", "site", siteID, 1)
			writeJSON(w, http.StatusOK, row)
			return
		}
	}
	writeErr(w, http.StatusNotFound, "not_found", "No such shop for this merchant.")
}

func (s *Server) handleAdminSiteCameras(w http.ResponseWriter, r *http.Request) {
	c, ok := s.clientForAdmin(w, r)
	if !ok {
		return
	}
	siteID, ok := s.siteForAdmin(w, r, c.ID)
	if !ok {
		return
	}
	rows, err := s.Store.Cameras(r.Context(), c.ID, siteID)
	if err != nil {
		s.serverError(w, "admin cameras", err)
		return
	}
	s.auditAdminRead(r, c.ID, "admin.cameras.read", "site", siteID, len(rows))
	writeJSON(w, http.StatusOK, AdminCameras(rows))
}

func (s *Server) handleAdminSiteCamera(w http.ResponseWriter, r *http.Request) {
	c, ok := s.clientForAdmin(w, r)
	if !ok {
		return
	}
	siteID, ok := s.siteForAdmin(w, r, c.ID)
	if !ok {
		return
	}
	camID, err := s.Store.AdminCameraID(r.Context(), c.ID, siteID, r.PathValue("camera"))
	if err != nil {
		s.serverError(w, "admin camera", err)
		return
	}
	if camID == "" {
		writeErr(w, http.StatusNotFound, "not_found", "No such camera for this shop.")
		return
	}
	rows, err := s.Store.Cameras(r.Context(), c.ID, siteID)
	if err != nil {
		s.serverError(w, "admin camera", err)
		return
	}
	for _, row := range rows {
		if row.ID == camID {
			s.auditAdminRead(r, c.ID, "admin.camera.read", "camera", camID, 1)
			writeJSON(w, http.StatusOK, adminCamera(row))
			return
		}
	}
	writeErr(w, http.StatusNotFound, "not_found", "No such camera for this shop.")
}

func (s *Server) handleAdminMonitoringSummary(w http.ResponseWriter, r *http.Request) {
	out, err := s.Store.PlatformSummary(r.Context())
	if err != nil {
		s.serverError(w, "platform summary", err)
		return
	}
	// No audit row: this is counts across the platform, naming no merchant and
	// no person. Logging a header strip that a console refreshes on a timer
	// would bury the reads that are actually worth finding.
	writeJSON(w, http.StatusOK, out)
}

// auditAdminRead records a platform admin reading inside one merchant.
//
// Below the merchant list, every read is somebody outside a company looking at
// that company's estate. "Who looked at my shops" has to be answerable for the
// same reason it does for face images, and an admin is exactly the account for
// which nothing else in the system would leave a trace.
func (s *Server) auditAdminRead(r *http.Request, clientID, action, entity, entityID string, n int) {
	p := PrincipalFrom(r.Context())
	s.Store.Audit(r.Context(), AuditEntry{
		ClientID: clientID, ActorID: p.UserID, ActorKind: "admin",
		Action: action, Entity: entity, EntityID: entityID,
		Detail: map[string]any{"path": r.URL.Path, "rows": n},
	})
}