package server

import (
	"database/sql"
	"log/slog"
	"net/http"

	"github.com/google/uuid"

	"git.coopcloud.tech/wiki-cafe/member-console/internal/identity"
	"git.coopcloud.tech/wiki-cafe/member-console/internal/systemtenant"
)

// PersonListViewModel represents one row of the People directory
// (GET /operator/persons). Distinct from PersonViewModel (the resolved
// person-detail projection): this carries only what the directory row
// needs, plus the email's verified state and the system-identity marker.
type PersonListViewModel struct {
	PersonID string
	// DisplayName and Email are the directory's search-matched fields
	// (operator-list-scale: "people: display name and email").
	DisplayName   string
	Email         string
	EmailVerified bool
	Status        string
	// JoinedAt is CreatedAt formatted like every other operator list date
	// ("Jan 2, 2006").
	JoinedAt string
}

// PersonsData is the body data for operator_persons.html.
type PersonsData struct {
	Persons []PersonListViewModel
	Error   string
	// Nav is the list-controls view model (operator-list-scale): search
	// and the true-total pager. People has no status facet, so Nav.Facet /
	// FacetOptions stay unset. Its Filtered() decides whether an empty
	// Persons slice renders the no-match state or the directory's true-
	// empty state.
	Nav ListNav
}

// systemPersonID resolves the person_id of the reserved system person —
// the owner of the System tenant (systemtenant.OrgType). The directory
// EXCLUDES that person (maintainer decision 2026-08-23): it is
// infrastructure that never "joined" — a synthetic non-loginable user
// (urn: OIDC subject no IdP can issue) with a non-routable .invalid email,
// existing only because organizations.owner_person_id is NOT NULL and the
// System tenant needs an owner — so listing it among members would pollute
// the newest-joined view. It stays visible in the organizations context as
// the System tenant's owner. Detected structurally — the person is the
// owner_person_id of the organization whose org_type is the reserved
// systemtenant.OrgType — never by matching name or email. Returns ""
// (excludes nothing) when the System tenant hasn't been provisioned yet or
// the lookup fails — degrading to an unfiltered directory rather than
// failing the page.
func (h *OperatorPartialsHandler) systemPersonID(r *http.Request) string {
	orgs, err := h.OrgQ.ListOrganizationsByType(r.Context(), systemtenant.OrgType)
	if err != nil || len(orgs) == 0 {
		return ""
	}
	return orgs[0].OwnerPersonID
}

// GetPersonsPage handles GET /operator/persons — the People directory
// (operator-people-directory D6): a searchable, paginated list of every
// person except the reserved system person, newest-joined first, governed
// by the operator-list-scale contract. Rows link to the existing person
// detail at /operator/persons/{personID}.
func (h *OperatorPartialsHandler) GetPersonsPage(w http.ResponseWriter, r *http.Request) {
	params := ParseListParams(r, "") // People has no status facet.
	bodyData := PersonsData{}

	var excludeID uuid.NullUUID
	if sysPersonID := h.systemPersonID(r); sysPersonID != "" {
		if id, pErr := uuid.Parse(sysPersonID); pErr == nil {
			excludeID = uuid.NullUUID{UUID: id, Valid: true}
		}
	}

	rows, total, err := FetchPage(&params, func(limit, offset int32) ([]identity.ListPersonsPageRow, int64, error) {
		page, pErr := h.IdentityQ.ListPersonsPage(r.Context(), identity.ListPersonsPageParams{
			Q:               sql.NullString{String: params.Q, Valid: params.Q != ""},
			ExcludePersonID: excludeID,
			PageLimit:       limit,
			PageOffset:      offset,
		})
		if pErr != nil {
			return nil, 0, pErr
		}
		var total int64
		if len(page) > 0 {
			total = page[0].TotalCount
		}
		return page, total, nil
	})
	if err != nil {
		h.Logger.Error("failed to list persons", slog.Any("error", err))
		bodyData.Error = "Failed to retrieve persons"
	} else {
		vms := make([]PersonListViewModel, len(rows))
		for i, p := range rows {
			vms[i] = PersonListViewModel{
				PersonID:      p.PersonID,
				DisplayName:   p.DisplayName,
				Email:         p.PrimaryEmail,
				EmailVerified: p.PrimaryEmailVerified,
				Status:        p.Status,
				JoinedAt:      p.CreatedAt.Format("Jan 2, 2006"),
			}
		}
		bodyData.Persons = vms
	}

	bodyData.Nav = ListNav{
		BasePath:          "/operator/persons",
		SearchPlaceholder: "Search by name or email",
		Q:                 params.Q,
		Page:              params.Page,
		Total:             total,
	}

	page := h.buildOperatorPageData(r)
	page.IAPosition = "runtime:persons"
	page.ActiveCapability = "persons"
	page.BodyTemplate = "operator_persons.html"
	page.BodyData = bodyData

	h.Templates.Render(w, "operator.html", page)
}