package repository

import (
	"context"
	"encoding/json"
	"errors"
	"strings"

	"github.com/google/uuid"
	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgconn"
)

// ScaleDefinitionWriteInput is explore-side metadata payload (no status).
type ScaleDefinitionWriteInput struct {
	Slug        string
	Title       string
	Description string
}

// CreateScaleDefinitionWithAudit inserts draft scale metadata + audit.
func (r *ScaleRepo) CreateScaleDefinitionWithAudit(
	ctx context.Context, adminID uuid.UUID, in ScaleDefinitionWriteInput, meta json.RawMessage,
) (*ScaleAdminItem, error) {
	tx, err := r.Pool.Begin(ctx)
	if err != nil {
		return nil, err
	}
	defer tx.Rollback(ctx)
	var it ScaleAdminItem
	err = tx.QueryRow(ctx, `
		INSERT INTO scales(slug, title, description, status)
		VALUES ($1,$2,$3,'draft')
		RETURNING id, slug, title, description, status`,
		in.Slug, in.Title, in.Description,
	).Scan(&it.ID, &it.Slug, &it.Title, &it.Description, &it.Status)
	if err != nil {
		return nil, mapScaleDefinitionWriteErr(err)
	}
	if meta == nil {
		meta = json.RawMessage(`{}`)
	}
	if _, err := tx.Exec(ctx, `
		INSERT INTO admin_audit_logs(admin_id, action, target_type, target_id, meta)
		VALUES ($1,'explore.scale_definition.create','scale',$2,$3)`,
		adminID, it.ID.String(), meta,
	); err != nil {
		return nil, err
	}
	if err := tx.Commit(ctx); err != nil {
		return nil, err
	}
	return &it, nil
}

// UpdateScaleDefinitionWithAudit updates metadata only (never status).
func (r *ScaleRepo) UpdateScaleDefinitionWithAudit(
	ctx context.Context, adminID, id uuid.UUID, in ScaleDefinitionWriteInput, meta json.RawMessage,
) (*ScaleAdminItem, error) {
	tx, err := r.Pool.Begin(ctx)
	if err != nil {
		return nil, err
	}
	defer tx.Rollback(ctx)
	var it ScaleAdminItem
	err = tx.QueryRow(ctx, `
		UPDATE scales
		SET slug=$2, title=$3, description=$4, updated_at=now()
		WHERE id=$1 AND deleted_at IS NULL
		RETURNING id, slug, title, description, status`,
		id, in.Slug, in.Title, in.Description,
	).Scan(&it.ID, &it.Slug, &it.Title, &it.Description, &it.Status)
	if errors.Is(err, pgx.ErrNoRows) {
		return nil, pgx.ErrNoRows
	}
	if err != nil {
		return nil, mapScaleDefinitionWriteErr(err)
	}
	if meta == nil {
		meta = json.RawMessage(`{}`)
	}
	if _, err := tx.Exec(ctx, `
		INSERT INTO admin_audit_logs(admin_id, action, target_type, target_id, meta)
		VALUES ($1,'explore.scale_definition.update','scale',$2,$3)`,
		adminID, id.String(), meta,
	); err != nil {
		return nil, err
	}
	if err := tx.Commit(ctx); err != nil {
		return nil, err
	}
	return &it, nil
}

func mapScaleDefinitionWriteErr(err error) error {
	var pgErr *pgconn.PgError
	if errors.As(err, &pgErr) && pgErr.Code == "23505" {
		return errString("scale slug conflict")
	}
	return err
}

// ScaleSlugConflict reports unique violation.
func ScaleSlugConflict(err error) bool {
	return err != nil && strings.Contains(err.Error(), "scale slug conflict")
}