// Package setupstatus reports whether the application's initial setup has been
// completed. Setup is considered complete as soon as at least one admin user
// exists, regardless of how that user was created (setup wizard, API, or a
// future CLI). This keeps the setup gate a derived property of real data
// rather than a manually-flipped flag that can drift out of sync.
package setupstatus

import (
	"context"
	"sync"
	"time"
)

// AdminCounter is satisfied by *database.Queries. It is defined as an interface
// here so this package does not import the database package, keeping the
// dependency graph flat and avoiding import cycles.
type AdminCounter interface {
	CountAdmins(ctx context.Context) (int64, error)
}

var (
	cacheMu       sync.RWMutex
	cacheComplete bool = true
	cacheExpiry   time.Time
	cacheTTL           = 10 * time.Second
)

// IsSetupComplete reports whether setup is complete. Setup is complete when at
// least one admin user exists. A short in-memory cache avoids hammering the
// database on every request. On a database error the function fails open
// (returns true) so a transient outage does not lock users out of the app.
func IsSetupComplete(ctx context.Context, q AdminCounter) bool {
	cacheMu.RLock()
	if time.Now().Before(cacheExpiry) {
		complete := cacheComplete
		cacheMu.RUnlock()
		return complete
	}
	cacheMu.RUnlock()

	count, err := q.CountAdmins(ctx)
	complete := true
	if err == nil {
		complete = count > 0
	}

	cacheMu.Lock()
	cacheComplete = complete
	cacheExpiry = time.Now().Add(cacheTTL)
	cacheMu.Unlock()
	return complete
}

// Invalidate clears the cached setup status so the next call to IsSetupComplete
// re-reads from the database. Call this after any write that could change the
// admin user count (user creation, role promotion/demotion, user deletion).
func Invalidate() {
	cacheMu.Lock()
	cacheComplete = true
	cacheExpiry = time.Time{}
	cacheMu.Unlock()
}