Initial grus version

3 files changed, 144 insertions, 0 deletions

diff --git a/storage/getdir_unix.go b/storage/getdir_unix.go
new file mode 100644
index 0000000..29bedbe
--- /dev/null
+++ b/storage/getdir_unix.go
@@ -0,0 +1,37 @@
+// +build linux netbsd openbsd freebsd dragonfly
+
+package storage
+
+import (
+	"fmt"
+	"os"
+)
+
+// GetDir returns grus data directory. Check if the user has set
+// GRUS_DIR, if not then check if XDG_DATA_HOME is set & if that is
+// not set then assume it to be the default value which is
+// $HOME/.local/share according to XDG Base Directory Specification.
+func GetDir() string {
+	cacheDir := SysDir()
+
+	// Grus cache directory is cacheDir/grus.
+	grusCacheDir := fmt.Sprintf("%s/%s", cacheDir,
+		"grus")
+
+	return grusCacheDir
+}
+
+// SysDir returns the system data directory, this is useful for unveil in
+// OpenBSD.
+func SysDir() string {
+	cacheDir := os.Getenv("GRUS_DIR")
+	if len(cacheDir) == 0 {
+		cacheDir = os.Getenv("XDG_DATA_HOME")
+	}
+	if len(cacheDir) == 0 {
+		cacheDir = fmt.Sprintf("%s/%s/%s", os.Getenv("HOME"),
+			".local", "share")
+	}
+
+	return cacheDir
+}
diff --git a/storage/init.go b/storage/init.go
new file mode 100644
index 0000000..9894c5b
--- /dev/null
+++ b/storage/init.go
@@ -0,0 +1,63 @@
+package storage
+
+import (
+	"database/sql"
+	"fmt"
+	"log"
+
+	_ "github.com/mattn/go-sqlite3"
+)
+
+// initErr will log the error and close the database connection if
+// necessary.
+func initErr(db *DB, err error) {
+	if db.Conn != nil {
+		db.Conn.Close()
+	}
+	log.Fatalf("Initialization Error :: %s", err.Error())
+}
+
+func initDB(db *DB) {
+	var err error
+
+	db.Path = fmt.Sprintf("%s/grus.db", GetDir())
+
+	db.Conn, err = sql.Open("sqlite3", db.Path)
+	if err != nil {
+		log.Printf("storage/init.go: %s\n",
+			"Failed to open database connection")
+		initErr(db, err)
+	}
+
+	sqlstmt := []string{
+		`CREATE TABLE IF NOT EXISTS words (
+        word   TEXT PRIMARY KEY NOT NULL,
+        sorted TEXT NOT NULL);`,
+		`INSERT INTO words(word, lexical)
+        values("grus", "grsu");`,
+	}
+
+	// We range over statements and execute them one by one, this
+	// is during initialization so it doesn't matter if it takes
+	// few more ms. This way we know which statement caused the
+	// program to fail.
+	for _, s := range sqlstmt {
+		stmt, err := db.Conn.Prepare(s)
+
+		if err != nil {
+			log.Printf("storage/init.go: %s\n",
+				"failed to prepare statement")
+			log.Println(s)
+			initErr(db, err)
+		}
+
+		_, err = stmt.Exec()
+		stmt.Close()
+		if err != nil {
+			log.Printf("storage/init.go: %s\n",
+				"failed to execute statement")
+			log.Println(s)
+			initErr(db, err)
+		}
+	}
+}
diff --git a/storage/storage.go b/storage/storage.go
new file mode 100644
index 0000000..9aa1a57
--- /dev/null
+++ b/storage/storage.go
@@ -0,0 +1,44 @@
+package storage
+
+import (
+	"database/sql"
+	"fmt"
+	"log"
+	"sync"
+)
+
+// DB holds the database connection, mutex & path.
+type DB struct {
+	Path string
+	Mu   *sync.RWMutex
+	Conn *sql.DB
+}
+
+// Init initializes the database.
+func Init() *DB {
+	db := DB{
+		Mu: new(sync.RWMutex),
+	}
+
+	initDB(&db)
+	return &db
+}
+
+// InitConn initializes database connection.
+func InitConn() *DB {
+	var err error
+	db := DB{
+		Mu: new(sync.RWMutex),
+	}
+
+	db.Path = fmt.Sprintf("%s/grus.db", GetDir())
+
+	db.Conn, err = sql.Open("sqlite3", db.Path)
+	if err != nil {
+		log.Printf("storage/init.go: %s\n",
+			"Failed to open database connection")
+		initErr(&db, err)
+	}
+
+	return &db
+}