package duckdb_test

import (
	"testing"

	dbv2 "git.fsdpf.net/go/db"
	"git.fsdpf.net/go/db/dialect/duckdb"

	"github.com/stretchr/testify/assert"
)

func TestDialectOptions(t *testing.T) {
	opts := duckdb.DialectOptions()
	assert.NotNil(t, opts)
	assert.Equal(t, '"', opts.QuoteRune)
	assert.True(t, opts.IncludePlaceholderNum)
	assert.Equal(t, []byte("$"), opts.PlaceHolderFragment)
	assert.True(t, opts.SupportsReturn)
	assert.True(t, opts.SupportsConflictTarget)
	assert.True(t, opts.SupportsWithCTE)
	assert.True(t, opts.SupportsDistinctOn)
	assert.True(t, opts.SupportsWindowFunction)
}

func TestDialectRegistration(t *testing.T) {
	// Verify the dialect is registered
	dialect := dbv2.GetDialect("duckdb")
	assert.NotNil(t, dialect)
}

func TestSelectSQL(t *testing.T) {
	db := dbv2.Dialect("duckdb")

	ds := db.From("users")
	sql, _, err := ds.ToSQL()
	assert.NoError(t, err)
	assert.Equal(t, `SELECT * FROM "users"`, sql)

	ds = db.From("users").Select("id", "name")
	sql, _, err = ds.ToSQL()
	assert.NoError(t, err)
	assert.Equal(t, `SELECT "id", "name" FROM "users"`, sql)

	ds = db.From("users").Where(dbv2.C("id").Eq(1))
	sql, _, err = ds.ToSQL()
	assert.NoError(t, err)
	assert.Equal(t, `SELECT * FROM "users" WHERE ("id" = 1)`, sql)
}

func TestPreparedStatement(t *testing.T) {
	db := dbv2.Dialect("duckdb")

	ds := db.From("users").Prepared(true).Where(dbv2.C("id").Eq(1))
	sql, args, err := ds.ToSQL()
	assert.NoError(t, err)
	assert.Equal(t, `SELECT * FROM "users" WHERE ("id" = $1)`, sql)
	assert.Equal(t, []interface{}{int64(1)}, args)

	ds = db.From("users").Prepared(true).Where(dbv2.C("name").Eq("John"))
	sql, args, err = ds.ToSQL()
	assert.NoError(t, err)
	assert.Equal(t, `SELECT * FROM "users" WHERE ("name" = $1)`, sql)
	assert.Equal(t, []interface{}{"John"}, args)
}

func TestInsertSQL(t *testing.T) {
	db := dbv2.Dialect("duckdb")

	ds := db.Insert("users").Rows(dbv2.Record{"id": 1, "name": "John"})
	sql, _, err := ds.ToSQL()
	assert.NoError(t, err)
	assert.Contains(t, sql, `INSERT INTO "users"`)
	assert.Contains(t, sql, `"id"`)
	assert.Contains(t, sql, `"name"`)
}

func TestUpdateSQL(t *testing.T) {
	db := dbv2.Dialect("duckdb")

	ds := db.Update("users").Set(dbv2.Record{"name": "Jane"}).Where(dbv2.C("id").Eq(1))
	sql, _, err := ds.ToSQL()
	assert.NoError(t, err)
	assert.Contains(t, sql, `UPDATE "users"`)
	assert.Contains(t, sql, `"name"`)
	assert.Contains(t, sql, `WHERE ("id" = 1)`)
}

func TestDeleteSQL(t *testing.T) {
	db := dbv2.Dialect("duckdb")

	ds := db.Delete("users").Where(dbv2.C("id").Eq(1))
	sql, _, err := ds.ToSQL()
	assert.NoError(t, err)
	assert.Equal(t, `DELETE FROM "users" WHERE ("id" = 1)`, sql)
}

func TestJoinSQL(t *testing.T) {
	db := dbv2.Dialect("duckdb")

	ds := db.From("users").
		Join(dbv2.T("orders"), dbv2.On(dbv2.Ex{"users.id": dbv2.I("orders.user_id")})).
		Select("users.name", "orders.total")
	sql, _, err := ds.ToSQL()
	assert.NoError(t, err)
	assert.Contains(t, sql, `FROM "users"`)
	assert.Contains(t, sql, `INNER JOIN "orders"`)
	assert.Contains(t, sql, `ON ("users"."id" = "orders"."user_id")`)
}

func TestRegexpSQL(t *testing.T) {
	db := dbv2.Dialect("duckdb")

	// RegexpLike → regexp_matches(col, pattern)
	ds := db.From("docs").Where(dbv2.C("content").RegexpLike("简介"))
	sql, _, err := ds.ToSQL()
	assert.NoError(t, err)
	assert.Equal(t, `SELECT * FROM "docs" WHERE regexp_matches("content", '简介')`, sql)

	// RegexpILike → 同样生成 regexp_matches
	ds = db.From("docs").Where(dbv2.C("content").RegexpILike("简介"))
	sql, _, err = ds.ToSQL()
	assert.NoError(t, err)
	assert.Equal(t, `SELECT * FROM "docs" WHERE regexp_matches("content", '简介')`, sql)
}

func TestRegexpPreparedSQL(t *testing.T) {
	db := dbv2.Dialect("duckdb")

	ds := db.From("docs").Prepared(true).Where(dbv2.C("content").RegexpLike("简介"))
	sql, args, err := ds.ToSQL()
	assert.NoError(t, err)
	assert.Equal(t, `SELECT * FROM "docs" WHERE regexp_matches("content", $1)`, sql)
	assert.Equal(t, []interface{}{"简介"}, args)
}

func TestWindowFunction(t *testing.T) {
	db := dbv2.Dialect("duckdb")

	ds := db.From("sales").
		Select(
			"product",
			"amount",
			dbv2.ROW_NUMBER().Over(dbv2.W().PartitionBy("product").OrderBy(dbv2.C("amount").Desc())).As("rank"),
		)
	sql, _, err := ds.ToSQL()
	assert.NoError(t, err)
	assert.Contains(t, sql, `ROW_NUMBER()`)
	assert.Contains(t, sql, `OVER`)
	assert.Contains(t, sql, `PARTITION BY`)
}

func TestCTE(t *testing.T) {
	db := dbv2.Dialect("duckdb")

	cte := db.From("users").Where(dbv2.C("active").IsTrue())
	ds := db.From("active_users").With("active_users", cte).Select("*")
	sql, _, err := ds.ToSQL()
	assert.NoError(t, err)
	assert.Contains(t, sql, `WITH active_users AS`)
	assert.Contains(t, sql, `SELECT * FROM "users" WHERE ("active" IS TRUE)`)
}