package clientapi

import (
	"net/http"

	"github.com/dariuszjaniak/warp/server/internal/httputil"
	"github.com/dariuszjaniak/warp/server/internal/userapi"
)

// changePasswordRequest is the body of POST /account/password.
type changePasswordRequest struct {
	NewPassword string `json:"new_password"`

	// LogoutDevices defaults to true, which is why it is a pointer: a
	// client that says nothing gets every other session logged out.
	LogoutDevices *bool `json:"logout_devices"`

	Auth *uiaRequest `json:"auth"`
}

// handleChangePassword implements POST /_matrix/client/v3/account/password.
//
// The current password is asked for again first, through the same
// interactive authentication as deleting a device, and for the same
// reason: a stolen access token must not be enough to lock the owner out.
// The session the change is made from stays logged in; with
// logout_devices, every other one is logged out.
//
// An application service acting as one of its users skips the
// re-authentication: its users have no password to ask for, and the
// service's token is already the strongest credential involved.
func (c *ClientAPI) handleChangePassword(w http.ResponseWriter, r *http.Request, auth userapi.Authenticated) error {
	var req changePasswordRequest
	if err := httputil.DecodeJSON(w, r, &req); err != nil {
		return err
	}

	sessionID := ""
	if auth.AppService == "" {
		flows := []uiaFlow{{Stages: []string{stagePassword}}}
		var done bool
		var err error
		sessionID, done, err = c.beginOrAdvanceUIA(w, flows, req.Auth,
			func(_ string, stage *uiaRequest) (*httputil.MatrixError, error) {
				return c.passwordStage(r, auth, stage)
			})
		if err != nil || !done {
			return err
		}
	}

	if req.NewPassword == "" {
		return httputil.MissingParam("new_password is required")
	}
	if len(req.NewPassword) > userapi.MaxPasswordLength {
		return httputil.NewError(http.StatusBadRequest, httputil.ErrCodeWeakPassword,
			"Password must be at most %d bytes", userapi.MaxPasswordLength)
	}
	logout := req.LogoutDevices == nil || *req.LogoutDevices

	if err := c.users.ChangePassword(r.Context(), auth.Localpart, req.NewPassword, logout, auth.DeviceID); err != nil {
		return err
	}
	c.uia.remove(sessionID)
	httputil.WriteJSON(w, http.StatusOK, struct{}{})
	return nil
}

// deactivateRequest is the body of POST /account/deactivate.
type deactivateRequest struct {
	// Erase asks for the account's profile to be forgotten as well.
	Erase bool `json:"erase"`

	Auth *uiaRequest `json:"auth"`
}

// deactivateResponse is its answer. Warp keeps no third-party identifiers
// and talks to no identity server, so there was nothing to unbind.
type deactivateResponse struct {
	IDServerUnbindResult string `json:"id_server_unbind_result"`
}

// handleDeactivate implements POST /_matrix/client/v3/account/deactivate:
// the user closing their own account, behind a re-entered password.
func (c *ClientAPI) handleDeactivate(w http.ResponseWriter, r *http.Request, auth userapi.Authenticated) error {
	var req deactivateRequest
	if err := httputil.DecodeJSON(w, r, &req); err != nil {
		return err
	}

	sessionID := ""
	if auth.AppService == "" {
		flows := []uiaFlow{{Stages: []string{stagePassword}}}
		var done bool
		var err error
		sessionID, done, err = c.beginOrAdvanceUIA(w, flows, req.Auth,
			func(_ string, stage *uiaRequest) (*httputil.MatrixError, error) {
				return c.passwordStage(r, auth, stage)
			})
		if err != nil || !done {
			return err
		}
	}

	if err := c.users.DeactivateAccount(r.Context(), auth.Localpart, req.Erase); err != nil {
		return err
	}
	c.uia.remove(sessionID)
	httputil.WriteJSON(w, http.StatusOK, deactivateResponse{IDServerUnbindResult: "no-support"})
	return nil
}