package lagoon

import (
	"context"
	"database/sql"
	"fmt"

	"github.com/go-gormigrate/gormigrate/v2"
	"github.com/riverqueue/river/riverdriver/riverdatabasesql"
	"github.com/riverqueue/river/rivermigrate"
	"gorm.io/gorm"
)

const (
	// QueueHistoryID is the migration history id of the framework job-queue
	// set. Its history table is summer_migrations_summercms_conga.
	QueueHistoryID = "summercms.conga"
	// JobsTable is the framework job record table. Its columns match the
	// WinterCMS apparatus jobs table plus the internal river_job_id link.
	JobsTable = "summer_jobs"
	// RiverSchemaVersion pins the River schema the framework migrates to, so a
	// River upgrade never applies new DDL without a new framework migration.
	RiverSchemaVersion = 7
)

// QueueMigrations returns the framework job-queue migration set: River's
// schema pinned at RiverSchemaVersion, then the summer_jobs record table.
// River's migrator runs each of its own steps in a separate transaction on
// sqlDB, because some River migrations cannot share one transaction.
func QueueMigrations(sqlDB *sql.DB) []*gormigrate.Migration {
	return []*gormigrate.Migration{
		{
			ID: "202609290001_river_schema",
			Migrate: func(tx *gorm.DB) error {
				return migrateRiver(txContext(tx), sqlDB, rivermigrate.DirectionUp, &rivermigrate.MigrateOpts{TargetVersion: RiverSchemaVersion})
			},
			Rollback: func(tx *gorm.DB) error {
				// TargetVersion -1 applies every down step, removing River's schema.
				return migrateRiver(txContext(tx), sqlDB, rivermigrate.DirectionDown, &rivermigrate.MigrateOpts{TargetVersion: -1})
			},
		},
		{
			ID: "202609290002_summer_jobs",
			Migrate: func(tx *gorm.DB) error {
				return tx.Exec(`CREATE TABLE IF NOT EXISTS summer_jobs (
	id SERIAL PRIMARY KEY,
	label VARCHAR(255) NOT NULL,
	status INTEGER NOT NULL DEFAULT 0,
	progress INTEGER NOT NULL DEFAULT 0,
	progress_max INTEGER NOT NULL DEFAULT 0,
	user_id INTEGER NULL,
	is_admin BOOLEAN NOT NULL DEFAULT FALSE,
	is_canceled BOOLEAN NOT NULL DEFAULT FALSE,
	metadata TEXT NOT NULL,
	river_job_id BIGINT NULL,
	created_at TIMESTAMPTZ NULL,
	updated_at TIMESTAMPTZ NULL
)`).Error
			},
			Rollback: func(tx *gorm.DB) error {
				return tx.Exec(`DROP TABLE IF EXISTS summer_jobs`).Error
			},
		},
	}
}

func migrateRiver(ctx context.Context, sqlDB *sql.DB, dir rivermigrate.Direction, opts *rivermigrate.MigrateOpts) error {
	if sqlDB == nil {
		return fmt.Errorf("lagoon: river migrate: sql db is nil")
	}
	m, err := rivermigrate.New(riverdatabasesql.New(sqlDB), nil)
	if err != nil {
		return fmt.Errorf("lagoon: river migrate: %w", err)
	}
	if _, err := m.Migrate(ctx, dir, opts); err != nil {
		return fmt.Errorf("lagoon: river migrate %s: %w", dir, err)
	}
	return nil
}

func txContext(tx *gorm.DB) context.Context {
	if tx != nil && tx.Statement != nil && tx.Statement.Context != nil {
		return tx.Statement.Context
	}
	return context.Background()
}