package duckdb

import (
	_ "github.com/marcboeker/go-duckdb"

	"git.fsdpf.net/go/db"
	"git.fsdpf.net/go/db/exp"
)

func DialectOptions() *db.SQLDialectOptions {
	do := db.DefaultDialectOptions()

	// DuckDB uses PostgreSQL-style placeholders ($1, $2, etc.)
	do.PlaceHolderFragment = []byte("$")
	do.IncludePlaceholderNum = true

	// DuckDB supports most PostgreSQL features
	do.SupportsReturn = true
	do.SupportsOrderByOnUpdate = false
	do.SupportsLimitOnUpdate = false
	do.SupportsOrderByOnDelete = false
	do.SupportsLimitOnDelete = false
	do.SupportsConflictUpdateWhere = true
	do.SupportsInsertIgnoreSyntax = false
	do.SupportsConflictTarget = true
	do.SupportsWithCTE = true
	do.SupportsWithCTERecursive = true
	do.SupportsDistinctOn = true
	do.SupportsWindowFunction = true

	// Use double quotes for identifiers (PostgreSQL-style)
	do.QuoteRune = '"'

	// regexp_matches(col, pattern) 做部分匹配，等价于 MySQL REGEXP
	do.BooleanFunctionLookup = map[exp.BooleanOperation][]byte{
		exp.RegexpLikeOp:  []byte("regexp_matches"),
		exp.RegexpILikeOp: []byte("regexp_matches"),
	}

	return do
}

func init() {
	db.RegisterDialect("duckdb", DialectOptions())
}