package app

import (
	"context"
	"errors"
	"fmt"
	"strings"

	tea "charm.land/bubbletea/v2"

	"git.kebcloud.no/keb/lazysecrets/internal/provider"
	"git.kebcloud.no/keb/lazysecrets/internal/ui/panes"
)

// On a provider's row, the fourth pane describes its account: the fields
// the provider knows locally, then the groups the account is in, loaded
// once a session when first shown.

type groupsState struct {
	names   []string
	err     error
	loading bool
}

type groupsMsg struct {
	provider string
	names    []string
	err      error
}

// syncSourceDetail fills the pane for the selected row, loading the
// account's groups the first time.
func (m *Model) syncSourceDetail() tea.Cmd {
	acct, ok := m.selectedAccount()
	if !ok {
		m.srcDetail.Set("", nil)
		return nil
	}
	r, _ := m.sources.Selected()
	var fields []panes.Field
	for _, f := range acct.Fields {
		fields = append(fields, panes.Field{Label: f.Label, Value: f.Value})
	}
	var cmd tea.Cmd
	if g, ok := m.byID[r.provider].(provider.AccountGroups); ok {
		st, seen := m.groups[r.provider]
		if !seen {
			st = groupsState{loading: true}
			m.groups[r.provider] = st
			id, timeout := r.provider, m.timeout
			cmd = func() tea.Msg {
				ctx, cancel := context.WithTimeout(context.Background(), timeout)
				defer cancel()
				names, err := g.Groups(ctx)
				return groupsMsg{provider: id, names: names, err: err}
			}
		}
		fields = append(fields, groupFields(st)...)
	}
	m.srcDetail.Set("Account", fields)
	return cmd
}

// fieldName names a copied field: its label, or for a group, the group.
func fieldName(f panes.Field) string {
	if f.Label == "" || strings.HasPrefix(f.Label, "groups") {
		return "group " + f.Value
	}
	return f.Label
}

// groupFields are the groups' rows: labelled on the first.
func groupFields(st groupsState) []panes.Field {
	switch {
	case st.loading:
		return []panes.Field{{Label: "groups", Value: "loading…", Info: true}}
	case errors.Is(st.err, provider.ErrUnsupported):
		return nil
	case st.err != nil:
		return []panes.Field{{Label: "groups", Value: "couldn't list them: " + st.err.Error(), Info: true}}
	case len(st.names) == 0:
		return []panes.Field{{Label: "groups", Value: "none", Info: true}}
	}
	out := make([]panes.Field, len(st.names))
	for i, n := range st.names {
		out[i] = panes.Field{Value: n}
	}
	out[0].Label = fmt.Sprintf("groups %d", len(st.names))
	return out
}