package controlplane

import (
	"context"
	"encoding/json"
	"fmt"
)

func (s *Store) Overview(ctx context.Context) (Overview, error) {
	var result Overview
	err := s.db.QueryRow(ctx, `
		SELECT
			(SELECT generation FROM control_state WHERE singleton = TRUE),
			(SELECT count(*) FROM tenants WHERE status = 'active'),
			(SELECT count(*) FROM projects WHERE status = 'active'),
			(SELECT count(*) FROM api_keys WHERE status = 'active'),
			(SELECT count(*) FROM providers WHERE enabled = TRUE),
			(SELECT count(*) FROM models WHERE enabled = TRUE)`,
	).Scan(&result.Generation, &result.Tenants, &result.Projects, &result.APIKeys, &result.Providers, &result.Models)
	if err != nil {
		return Overview{}, fmt.Errorf("query control-plane overview: %w", err)
	}
	return result, nil
}

func (s *Store) ListTenants(ctx context.Context) ([]Tenant, error) {
	return s.ListTenantsFor(ctx, "")
}

func (s *Store) ListTenantsFor(ctx context.Context, tenantID string) ([]Tenant, error) {
	query := `SELECT id::text, slug, name, status, created_at FROM tenants`
	args := []any{}
	if tenantID != "" {
		query += ` WHERE id=$1`
		args = append(args, tenantID)
	}
	query += ` ORDER BY created_at DESC`
	rows, err := s.db.Query(ctx, query, args...)
	if err != nil {
		return nil, fmt.Errorf("query tenants: %w", err)
	}
	defer rows.Close()
	result := make([]Tenant, 0)
	for rows.Next() {
		var item Tenant
		if err := rows.Scan(&item.ID, &item.Slug, &item.Name, &item.Status, &item.CreatedAt); err != nil {
			return nil, fmt.Errorf("scan tenant: %w", err)
		}
		result = append(result, item)
	}
	return result, rows.Err()
}

func (s *Store) ListProjects(ctx context.Context) ([]Project, error) {
	return s.ListProjectsFor(ctx, "")
}

func (s *Store) ListProjectsFor(ctx context.Context, tenantID string) ([]Project, error) {
	query := `SELECT id::text, tenant_id::text, slug, name, status, created_at FROM projects`
	args := []any{}
	if tenantID != "" {
		query += ` WHERE tenant_id=$1`
		args = append(args, tenantID)
	}
	query += ` ORDER BY created_at DESC`
	rows, err := s.db.Query(ctx, query, args...)
	if err != nil {
		return nil, fmt.Errorf("query projects: %w", err)
	}
	defer rows.Close()
	result := make([]Project, 0)
	for rows.Next() {
		var item Project
		if err := rows.Scan(&item.ID, &item.TenantID, &item.Slug, &item.Name, &item.Status, &item.CreatedAt); err != nil {
			return nil, fmt.Errorf("scan project: %w", err)
		}
		result = append(result, item)
	}
	return result, rows.Err()
}

func (s *Store) ListAPIKeys(ctx context.Context) ([]APIKey, error) {
	return s.ListAPIKeysFor(ctx, "")
}

func (s *Store) ListAPIKeysFor(ctx context.Context, tenantID string) ([]APIKey, error) {
	query := `
		SELECT id::text, tenant_id::text, project_id::text, name, key_prefix, scopes, status, created_at
		FROM api_keys`
	args := []any{}
	if tenantID != "" {
		query += ` WHERE tenant_id=$1`
		args = append(args, tenantID)
	}
	query += ` ORDER BY created_at DESC`
	rows, err := s.db.Query(ctx, query, args...)
	if err != nil {
		return nil, fmt.Errorf("query API keys: %w", err)
	}
	defer rows.Close()
	result := make([]APIKey, 0)
	for rows.Next() {
		var item APIKey
		var scopesJSON []byte
		if err := rows.Scan(&item.ID, &item.TenantID, &item.ProjectID, &item.Name, &item.KeyPrefix, &scopesJSON, &item.Status, &item.CreatedAt); err != nil {
			return nil, fmt.Errorf("scan API key: %w", err)
		}
		if err := json.Unmarshal(scopesJSON, &item.Scopes); err != nil {
			return nil, fmt.Errorf("decode API key scopes: %w", err)
		}
		result = append(result, item)
	}
	return result, rows.Err()
}

func (s *Store) OverviewFor(ctx context.Context, tenantID string) (Overview, error) {
	if tenantID == "" {
		return s.Overview(ctx)
	}
	var result Overview
	err := s.db.QueryRow(ctx, `SELECT
		(SELECT generation FROM control_state WHERE singleton=TRUE),
		(SELECT count(*) FROM tenants WHERE id=$1 AND status='active'),
		(SELECT count(*) FROM projects WHERE tenant_id=$1 AND status='active'),
		(SELECT count(*) FROM api_keys WHERE tenant_id=$1 AND status='active'),
		0,
		(SELECT count(*) FROM models WHERE enabled=TRUE)`, tenantID,
	).Scan(&result.Generation, &result.Tenants, &result.Projects, &result.APIKeys, &result.Providers, &result.Models)
	if err != nil {
		return Overview{}, fmt.Errorf("query tenant overview: %w", err)
	}
	return result, nil
}

func (s *Store) ResourceTenantID(ctx context.Context, resource, id string) (string, error) {
	var query string
	switch resource {
	case "project":
		query = `SELECT tenant_id::text FROM projects WHERE id=$1`
	case "api_key":
		query = `SELECT tenant_id::text FROM api_keys WHERE id=$1`
	case "console_user":
		query = `SELECT COALESCE(tenant_id::text,'') FROM console_users WHERE id=$1`
	default:
		return "", ErrNotFound
	}
	var tenantID string
	if err := s.db.QueryRow(ctx, query, id).Scan(&tenantID); err != nil {
		return "", ErrNotFound
	}
	return tenantID, nil
}

func (s *Store) ListProviders(ctx context.Context) ([]Provider, error) {
	rows, err := s.db.Query(ctx, `
		SELECT p.id::text, p.name, p.protocol, p.base_url, p.enabled, count(r.id), p.created_at
		FROM providers p LEFT JOIN model_routes r ON r.provider_id = p.id
		GROUP BY p.id ORDER BY p.created_at DESC`)
	if err != nil {
		return nil, fmt.Errorf("query providers: %w", err)
	}
	defer rows.Close()
	result := make([]Provider, 0)
	for rows.Next() {
		var item Provider
		if err := rows.Scan(&item.ID, &item.Name, &item.Protocol, &item.BaseURL, &item.Enabled, &item.RouteCount, &item.CreatedAt); err != nil {
			return nil, fmt.Errorf("scan provider: %w", err)
		}
		result = append(result, item)
	}
	return result, rows.Err()
}

func (s *Store) ListModels(ctx context.Context) ([]Model, error) {
	rows, err := s.db.Query(ctx, `
		SELECT id::text, public_id, owned_by, input_price_micros_per_million,
		       output_price_micros_per_million, cache_read_price_micros_per_million,
		       cache_write_price_micros_per_million, enabled, created_at
		FROM models ORDER BY public_id`)
	if err != nil {
		return nil, fmt.Errorf("query models: %w", err)
	}
	models := make([]Model, 0)
	positions := make(map[string]int)
	for rows.Next() {
		var item Model
		if err := rows.Scan(&item.ID, &item.PublicID, &item.OwnedBy, &item.InputPriceMicrosPerMillion,
			&item.OutputPriceMicrosPerMillion, &item.CacheReadPriceMicrosPerMillion,
			&item.CacheWritePriceMicrosPerMillion, &item.Enabled, &item.CreatedAt); err != nil {
			rows.Close()
			return nil, fmt.Errorf("scan model: %w", err)
		}
		item.Routes = []Route{}
		positions[item.ID] = len(models)
		models = append(models, item)
	}
	if err := rows.Err(); err != nil {
		rows.Close()
		return nil, err
	}
	rows.Close()

	routeRows, err := s.db.Query(ctx, `
		SELECT r.id::text, r.model_id::text, r.provider_id::text, p.name, p.protocol,
		       r.upstream_model, r.priority, r.weight, r.enabled
		FROM model_routes r JOIN providers p ON p.id = r.provider_id
		ORDER BY r.priority, r.created_at`)
	if err != nil {
		return nil, fmt.Errorf("query model routes: %w", err)
	}
	defer routeRows.Close()
	for routeRows.Next() {
		var route Route
		var modelID string
		if err := routeRows.Scan(&route.ID, &modelID, &route.ProviderID, &route.ProviderName, &route.Protocol, &route.UpstreamModel, &route.Priority, &route.Weight, &route.Enabled); err != nil {
			return nil, fmt.Errorf("scan model route: %w", err)
		}
		if position, ok := positions[modelID]; ok {
			models[position].Routes = append(models[position].Routes, route)
		}
	}
	return models, routeRows.Err()
}