// +build gcc

package db

import (
	"fmt"
	"path"

	"github.com/jmhodges/levigo"

	. "github.com/tendermint/tmlibs/common"
)

func init() {
	dbCreator := func(name string, dir string) (DB, error) {
		return NewCLevelDB(name, dir)
	}
	registerDBCreator(LevelDBBackendStr, dbCreator, true)
	registerDBCreator(CLevelDBBackendStr, dbCreator, false)
}

type CLevelDB struct {
	db     *levigo.DB
	ro     *levigo.ReadOptions
	wo     *levigo.WriteOptions
	woSync *levigo.WriteOptions
}

func NewCLevelDB(name string, dir string) (*CLevelDB, error) {
	dbPath := path.Join(dir, name+".db")

	opts := levigo.NewOptions()
	opts.SetCache(levigo.NewLRUCache(1 << 30))
	opts.SetCreateIfMissing(true)
	db, err := levigo.Open(dbPath, opts)
	if err != nil {
		return nil, err
	}
	ro := levigo.NewReadOptions()
	wo := levigo.NewWriteOptions()
	woSync := levigo.NewWriteOptions()
	woSync.SetSync(true)
	database := &CLevelDB{
		db:     db,
		ro:     ro,
		wo:     wo,
		woSync: woSync,
	}
	return database, nil
}

func (db *CLevelDB) Get(key []byte) []byte {
	res, err := db.db.Get(db.ro, key)
	if err != nil {
		PanicCrisis(err)
	}
	return res
}

func (db *CLevelDB) Set(key []byte, value []byte) {
	err := db.db.Put(db.wo, key, value)
	if err != nil {
		PanicCrisis(err)
	}
}

func (db *CLevelDB) SetSync(key []byte, value []byte) {
	err := db.db.Put(db.woSync, key, value)
	if err != nil {
		PanicCrisis(err)
	}
}

func (db *CLevelDB) Delete(key []byte) {
	err := db.db.Delete(db.wo, key)
	if err != nil {
		PanicCrisis(err)
	}
}

func (db *CLevelDB) DeleteSync(key []byte) {
	err := db.db.Delete(db.woSync, key)
	if err != nil {
		PanicCrisis(err)
	}
}

func (db *CLevelDB) DB() *levigo.DB {
	return db.db
}

func (db *CLevelDB) Close() {
	db.db.Close()
	db.ro.Close()
	db.wo.Close()
	db.woSync.Close()
}

func (db *CLevelDB) Print() {
	iter := db.db.NewIterator(db.ro)
	defer iter.Close()
	for iter.Seek(nil); iter.Valid(); iter.Next() {
		key := iter.Key()
		value := iter.Value()
		fmt.Printf("[%X]:\t[%X]\n", key, value)
	}
}

func (db *CLevelDB) Stats() map[string]string {
	// TODO: Find the available properties for the C LevelDB implementation
	keys := []string{}

	stats := make(map[string]string)
	for _, key := range keys {
		str, err := db.db.GetProperty(key)
		if err == nil {
			stats[key] = str
		}
	}
	return stats
}

func (db *CLevelDB) Iterator() Iterator {
	return db.db.NewIterator(nil, nil)
}

func (db *CLevelDB) NewBatch() Batch {
	batch := levigo.NewWriteBatch()
	return &cLevelDBBatch{db, batch}
}

//--------------------------------------------------------------------------------

type cLevelDBBatch struct {
	db    *CLevelDB
	batch *levigo.WriteBatch
}

func (mBatch *cLevelDBBatch) Set(key, value []byte) {
	mBatch.batch.Put(key, value)
}

func (mBatch *cLevelDBBatch) Delete(key []byte) {
	mBatch.batch.Delete(key)
}

func (mBatch *cLevelDBBatch) Write() {
	err := mBatch.db.db.Write(mBatch.db.wo, mBatch.batch)
	if err != nil {
		PanicCrisis(err)
	}
}