package api

import (
	"github.com/vasyakrg/dns-autoresolver/internal/diff"
	"github.com/vasyakrg/dns-autoresolver/internal/store"
)

type registerRequest struct {
	Email    string `json:"email"`
	Password string `json:"password"`
}

type loginRequest struct {
	Email    string `json:"email"`
	Password string `json:"password"`
}

// userResponse and projectResponse deliberately expose only id/email and
// id/name — password_hash must never reach a client response.
type userResponse struct {
	ID    string `json:"id"`
	Email string `json:"email"`
}

type projectResponse struct {
	ID   string `json:"id"`
	Name string `json:"name"`
}

type authResponse struct {
	User    userResponse    `json:"user"`
	Project projectResponse `json:"project"`
}

func toAuthResponse(u store.User, p store.Project) authResponse {
	return authResponse{
		User:    userResponse{ID: u.ID.String(), Email: u.Email},
		Project: projectResponse{ID: p.ID.String(), Name: p.Name},
	}
}

type applyRequest struct {
	Updates []string `json:"updates"`
	Prunes  []string `json:"prunes"`
}

type recordView struct {
	Key      string   `json:"key"`
	Kind     string   `json:"kind"`
	Type     string   `json:"type"`
	Name     string   `json:"name"`
	Desired  []string `json:"desired,omitempty"`
	Actual   []string `json:"actual,omitempty"`
	ReadOnly bool     `json:"readOnly"`
}

type changesetResponse struct {
	Updates  []recordView `json:"updates"`
	Prunes   []recordView `json:"prunes"`
	ReadOnly []recordView `json:"readOnly"`
	InSync   int          `json:"inSyncCount"`
}

func toRecordView(d diff.RecordDiff) recordView {
	rv := recordView{Key: d.Key(), Kind: string(d.Kind), Type: string(d.Type), Name: d.Name, ReadOnly: d.ReadOnly}
	if d.Desired != nil {
		rv.Desired = d.Desired.Values
	}
	if d.Actual != nil {
		rv.Actual = d.Actual.Values
	}
	return rv
}

func toChangesetResponse(cs diff.Changeset) changesetResponse {
	// Initialise the slices so an empty changeset (e.g. a zone that exactly
	// matches its template right after a snapshot) marshals to [] rather than
	// null — a nil slice becomes JSON null, which crashes clients that call
	// .length/.map on the field.
	resp := changesetResponse{
		Updates:  []recordView{},
		Prunes:   []recordView{},
		ReadOnly: []recordView{},
	}
	for _, d := range cs.Updates() {
		resp.Updates = append(resp.Updates, toRecordView(d))
	}
	for _, d := range cs.Prunes() {
		resp.Prunes = append(resp.Prunes, toRecordView(d))
	}
	for _, d := range cs.Diffs {
		if d.ReadOnly {
			resp.ReadOnly = append(resp.ReadOnly, toRecordView(d))
		}
		if d.Kind == diff.InSync {
			resp.InSync++
		}
	}
	return resp
}