package billing

import (
	"context"
	"strings"
)

// EnsureDefaultFeatureSeeds idempotently seeds global section master switches
// (marketing + integrations forced OFF; other sections default ON). Plan feature
// overrides stay sparse: empty '{}' means unset and DefaultPlanFeatures /
// is_custom apply at resolve time.
//
// ASSUMPTION: There is no plans.features_customized flag. A non-empty
// plans.features JSON object means an admin customized the package - this
// seeder never overwrites it (except legacy-flagged plans — see
// EnsureLegacyPlanFeatureSeeds). Empty '{}' means unset.
// Custom / Enterprise (is_custom=true, non-legacy-name) resolve to all features ON.
// A1* with is_custom resolve to A1PaygPlanFeatures (Stores/Marketing/Integrations off).
// Legacy (A1 without is_custom / is_legacy) resolve to the image-nav matrix; empty rows are backfilled.
func (s *Service) EnsureDefaultFeatureSeeds(ctx context.Context) error {
	if s == nil || s.Pool == nil {
		return nil
	}
	if err := s.seedGlobalSectionGates(ctx); err != nil {
		return err
	}
	return s.EnsureLegacyDefaults(ctx)
}

// EnsureLegacyPlanFeatureSeeds idempotently applies the legacy sparse matrix to
// plans that are legacy by name or is_legacy flag.
//
// Rules:
//   - empty features → write SparseLegacyOverrides + mark is_legacy when column exists
//   - is_legacy=true → re-apply SparseLegacyOverrides (flagged cohort)
//   - non-empty customized (not enable-all) and not flagged → leave alone
func (s *Service) EnsureLegacyPlanFeatureSeeds(ctx context.Context) error {
	if s == nil || s.Pool == nil {
		return nil
	}
	rows, err := s.Pool.Query(ctx, `
		SELECT id, name, is_custom, COALESCE(is_legacy, false), COALESCE(features, '{}'::jsonb)
		FROM plans`)
	if err != nil {
		if isUndefinedColumn(err) {
			return s.ensureLegacyPlanFeatureSeedsWithoutFlag(ctx)
		}
		return err
	}
	defer rows.Close()
	type row struct {
		id       int64
		name     string
		isCustom bool
		isLegacy bool
		raw      []byte
	}
	var list []row
	for rows.Next() {
		var r row
		if err := rows.Scan(&r.id, &r.name, &r.isCustom, &r.isLegacy, &r.raw); err != nil {
			return err
		}
		list = append(list, r)
	}
	if err := rows.Err(); err != nil {
		return err
	}
	sparse := SparseLegacyOverrides()
	for _, r := range list {
		// Custom / PAYG deals (incl. A1 with is_custom) keep their own matrix —
		// never overwrite with legacy-sparse. A1 PAYG hygiene lives in ensureA1PaygPlanSemantics.
		if IsCustomPackage(r.name, r.isCustom) {
			continue
		}
		if !IsLegacyPlan(r.name, r.isLegacy) {
			continue
		}
		overrides, derr := decodeFeaturesJSON(r.raw)
		if derr != nil {
			return derr
		}
		shouldWrite := r.isLegacy || featuresMapEmpty(overrides)
		if !shouldWrite {
			continue
		}
		if _, err := s.SetPlanFeatures(ctx, r.id, sparse); err != nil {
			return err
		}
		if _, err := s.Pool.Exec(ctx, `
			UPDATE plans SET is_legacy = true, updated_at = now() WHERE id = $1 AND is_legacy = false`, r.id); err != nil {
			if isUndefinedColumn(err) {
				continue
			}
			return err
		}
	}
	return nil
}

func (s *Service) ensureLegacyPlanFeatureSeedsWithoutFlag(ctx context.Context) error {
	rows, err := s.Pool.Query(ctx, `
		SELECT id, name, is_custom, COALESCE(features, '{}'::jsonb)
		FROM plans`)
	if err != nil {
		if isUndefinedColumn(err) || isUndefinedRelation(err) {
			return nil
		}
		return err
	}
	defer rows.Close()
	sparse := SparseLegacyOverrides()
	for rows.Next() {
		var id int64
		var name string
		var isCustom bool
		var raw []byte
		if err := rows.Scan(&id, &name, &isCustom, &raw); err != nil {
			return err
		}
		if IsCustomPackage(name, isCustom) {
			continue
		}
		if !IsLegacyPlanName(name) {
			continue
		}
		overrides, derr := decodeFeaturesJSON(raw)
		if derr != nil {
			return derr
		}
		if !featuresMapEmpty(overrides) {
			continue
		}
		if _, err := s.SetPlanFeatures(ctx, id, sparse); err != nil {
			return err
		}
	}
	return rows.Err()
}

func (s *Service) seedGlobalSectionGates(ctx context.Context) error {
	for _, section := range FeatureSections {
		_, err := s.Pool.Exec(ctx, `
			INSERT INTO platform_feature_gates (gate_key, kind, enabled, updated_at)
			VALUES ($1, 'section', true, now())
			ON CONFLICT (gate_key) DO NOTHING`, section)
		if err != nil {
			if isUndefinedRelation(err) {
				return nil
			}
			return err
		}
	}
	// Work-mode defaults: keep Marketing + Integrations off platform-wide.
	// Upsert so restarts re-assert OFF even if an older seed left them ON.
	for _, section := range []string{"marketing", "integrations"} {
		_, err := s.Pool.Exec(ctx, `
			INSERT INTO platform_feature_gates (gate_key, kind, enabled, updated_at)
			VALUES ($1, 'section', false, now())
			ON CONFLICT (gate_key) DO UPDATE
			SET enabled = false,
			    updated_at = now()
			WHERE platform_feature_gates.enabled IS DISTINCT FROM false`, section)
		if err != nil {
			if isUndefinedRelation(err) {
				return nil
			}
			return err
		}
	}
	s.invalidateFeatureGatesCache()
	return nil
}

// SparseDefaultOverrides returns only the false keys from DefaultPlanFeatures
// (empty map for custom / all-on packages). Legacy plans return SparseLegacyOverrides.
// Useful for "reset to defaults" admin helpers without storing the full expanded matrix.
func SparseDefaultOverrides(planName string, isCustom bool) map[string]bool {
	return SparseDefaultOverridesEx(planName, isCustom, IsLegacyPlanName(planName))
}

// SparseDefaultOverridesEx includes an explicit is_legacy flag.
func SparseDefaultOverridesEx(planName string, isCustom, isLegacy bool) map[string]bool {
	if IsCustomPackage(planName, isCustom) {
		if IsLegacyPlanName(planName) {
			return SparseA1PaygOverrides()
		}
		return map[string]bool{}
	}
	if IsLegacyPlan(planName, isLegacy) {
		return SparseLegacyOverrides()
	}
	full := DefaultPlanFeaturesEx(planName, false, false)
	out := make(map[string]bool)
	for k, v := range full {
		if !v {
			out[k] = false
		}
	}
	return out
}

// NormalizePublicPlanName maps a plan name to the public ladder key used by
// DefaultPlanFeatures (free|starter|plus|growth|business|scale|enterprise|other).
func NormalizePublicPlanName(planName string) string {
	switch strings.ToLower(strings.TrimSpace(planName)) {
	case "", "free":
		return "free"
	case "starter", "plus":
		// Plus uses the Starter feature matrix (AI on, BYOK off).
		return "starter"
	case "growth":
		return "growth"
	case "business", "scale":
		return "business"
	case "enterprise":
		return "enterprise"
	default:
		return "other"
	}
}