package sqlite

import (
	"context"
	"database/sql"

	"github.com/pkg/errors"
	"gitlab.com/wpetit/goweb/logger"
)

type MigrateFunc func(ctx context.Context, tx *sql.Tx) error

var documentStoreMigrations = []MigrateFunc{
	documentStoreMigrationBaseSchema,
	documentStoreMigrationAddIDIndex,
	documentStoreMigrationAddRevisionColumn,
}

func documentStoreMigrationBaseSchema(ctx context.Context, tx *sql.Tx) error {
	query := `
		CREATE TABLE IF NOT EXISTS documents (
			id TEXT PRIMARY KEY,
			collection TEXT NOT NULL,
			data TEXT,
			created_at TIMESTAMP NOT NULL,
			updated_at TIMESTAMP NOT NULL,
			UNIQUE(id, collection) ON CONFLICT REPLACE
		);
	`

	if _, err := tx.ExecContext(ctx, query); err != nil {
		return errors.WithStack(err)
	}

	return nil
}

func documentStoreMigrationAddIDIndex(ctx context.Context, tx *sql.Tx) error {
	query := `
		CREATE INDEX IF NOT EXISTS collection_idx ON documents (collection);
	`

	if _, err := tx.ExecContext(ctx, query); err != nil {
		return errors.WithStack(err)
	}

	return nil
}

func documentStoreMigrationAddRevisionColumn(ctx context.Context, tx *sql.Tx) error {
	query := `PRAGMA table_info(documents)`

	rows, err := tx.QueryContext(ctx, query)
	if err != nil {
		return errors.WithStack(err)
	}

	defer func() {
		if err := rows.Close(); err != nil {
			logger.Error(ctx, "could not close rows", logger.CapturedE(errors.WithStack(err)))
		}
	}()

	var hasRevisionColumn bool

	for rows.Next() {
		var (
			id           int
			name         string
			dataType     string
			nullable     int
			defaultValue any
			primaryKey   int
		)

		if err := rows.Scan(&id, &name, &dataType, &nullable, &defaultValue, &primaryKey); err != nil {
			return errors.WithStack(err)
		}

		if name == "revision" {
			hasRevisionColumn = true
			break
		}
	}

	if err := rows.Err(); err != nil {
		return errors.WithStack(err)
	}

	if !hasRevisionColumn {
		query = `ALTER TABLE documents ADD COLUMN revision INTEGER DEFAULT 0`
		if _, err := tx.ExecContext(ctx, query); err != nil {
			return errors.WithStack(err)
		}
	}

	return nil
}