package hostguard

import (
	"context"
	"errors"
	"github.com/carlosframework/platform/internal/hostclaim"
)

func (g Guard) RetireInstallationWith(ctx context.Context, host string, captured Captured, check func(*hostclaim.Claim) error, fn func() error) error {
	return g.retireInstallationWith(ctx, host, captured, check, fn, nil)
}

// persist is injected by package tests to interrupt the record's durable write.
func (g Guard) retireInstallationWith(ctx context.Context, host string, captured Captured, check func(*hostclaim.Claim) error, fn func() error, persist func(*recordDir, record) error) error {
	if captured.Stamp == 0 || check == nil || fn == nil {
		return ErrInvalidInput
	}
	return g.locked(ctx, host, func(d *recordDir) error {
		c, err := g.fresh(ctx, host)
		if err != nil {
			return err
		}
		if c.Holder.Incarnation != captured.Incarnation {
			return ErrClaimIncarnation
		}
		if err := check(c); err != nil {
			return err
		}
		r, err := d.read(host)
		if err != nil {
			return err
		}
		if r.Incarnation != captured.Incarnation {
			return ErrRecordIncarnation
		}
		if r.ActiveStamp != 0 {
			if r.ActiveStamp != captured.Stamp {
				return ErrStampMismatch
			}
			r.retire()
			if persist == nil {
				persist = (*recordDir).write
			}
		} else {
			n := len(r.RetiredStamps)
			if n == 0 || r.RetiredStamps[n-1] != captured.Stamp {
				return ErrStampMismatch
			}
			if persist == nil {
				persist = func(d *recordDir, _ record) error { return d.sync(host) }
			}
		}
		if err := ctx.Err(); err != nil {
			return err
		}
		// An inactive record can be visible after rename without being durable.
		// Sync it on retries before the callback may move any artifact.
		if err := persist(d, r); err != nil {
			return err
		}
		if err := ctx.Err(); err != nil {
			return err
		}
		return fn()
	})
}

func (g Guard) WithNoInstallation(ctx context.Context, host, incarnation string, check func(*hostclaim.Claim) error, fn func() error) error {
	if incarnation == "" || check == nil || fn == nil {
		return ErrInvalidInput
	}
	return g.locked(ctx, host, func(d *recordDir) error {
		c, err := g.fresh(ctx, host)
		if err != nil {
			return err
		}
		if c.Holder.Incarnation != incarnation {
			return ErrClaimIncarnation
		}
		if err := check(c); err != nil {
			return err
		}
		if g.Root != nil {
			captured := Captured{Incarnation: incarnation, Stamp: c.Holder.Stamp}
			view, err := g.Root.viewLocked(host, captured)
			if err != nil {
				return err
			}
			if err = view.admit(host, captured, c.Holder.Session); err != nil {
				return err
			}
			if !view.Installation.Empty || view.Installation.Account != c.Holder.Account || view.Installation.App != c.Holder.App {
				return ErrStampMismatch
			}
			return fn()
		}
		_, err = d.read(host)
		if !errors.Is(err, ErrNoRecord) {
			if err != nil {
				return err
			}
			return ErrStampMismatch
		}
		if err := ctx.Err(); err != nil {
			return err
		}
		return fn()
	})
}