1 files changed, 75 insertions, 0 deletions
diff --git a/generateIterator.go b/generateIterator.go
new file mode 100644
index 0000000..a291c1e
--- /dev/null
+++ b/generateIterator.go
@@ -0,0 +1,75 @@
+package main
+
+import (
+	"fmt"
+	"io"
+)
+
+// only make one of these for each message in the protobuf file
+func newIter(w io.Writer, FRUIT, APPLE, APPLES, COLOR, LOCK string) {
+	fmt.Fprintln(w, "// DEFINE THE ITERATOR. is unique to the "+APPLE+" protobuf message")
+	fmt.Fprintln(w, "// itializes a new iterator.")
+	fmt.Fprintln(w, "func New"+APPLE+"Iterator(things []*"+APPLE+") *"+APPLE+"Iterator {")
+	fmt.Fprintln(w, "	return &"+APPLE+"Iterator{things: things}")
+	fmt.Fprintln(w, "}")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "// safely returns a slice of pointers to the FRUIT protobufs")
+	fmt.Fprintln(w, "func (x *"+FRUIT+") all() []*"+APPLE+" {")
+	fmt.Fprintln(w, "	"+LOCK+".RLock()")
+	fmt.Fprintln(w, "	defer "+LOCK+".RUnlock()")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "	// Create a new slice to hold pointers to each FRUIT")
+	fmt.Fprintln(w, "	var tmp []*"+APPLE+"")
+	fmt.Fprintln(w, "	tmp = make([]*"+APPLE+", len(x."+APPLES+"))")
+	fmt.Fprintln(w, "	for i, p := range x."+APPLES+" {")
+	fmt.Fprintln(w, "		tmp[i] = p // Copy pointers for safe iteration")
+	fmt.Fprintln(w, "	}")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "	return tmp")
+	fmt.Fprintln(w, "}")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "type "+APPLE+"Iterator struct {")
+	fmt.Fprintln(w, "	sync.RWMutex // this isn't getting used properly yet?")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "	things []*"+APPLE+"")
+	fmt.Fprintln(w, "	index  int")
+	fmt.Fprintln(w, "}")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "func (it *"+APPLE+"Iterator) Scan() bool {")
+	fmt.Fprintln(w, "	if it.index >= len(it.things) {")
+	fmt.Fprintln(w, "		return false")
+	fmt.Fprintln(w, "	}")
+	fmt.Fprintln(w, "	it.index++")
+	fmt.Fprintln(w, "	return true")
+	fmt.Fprintln(w, "}")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "// Next() returns the next thing in the array")
+	fmt.Fprintln(w, "func (it *"+APPLE+"Iterator) Next() *"+APPLE+" {")
+	fmt.Fprintln(w, "	if it.things[it.index-1] == nil {")
+	fmt.Fprintln(w, "		fmt.Println(\"Next() error in "+APPLE+"Iterator\", it.index)")
+	fmt.Fprintln(w, "	}")
+	fmt.Fprintln(w, "	return it.things[it.index-1]")
+	fmt.Fprintln(w, "}")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "// END DEFINE THE ITERATOR")
+	fmt.Fprintln(w, "")
+}
+
+func newSortBy(w io.Writer, FRUIT, APPLE, COLOR string) {
+	fmt.Fprintln(w, "// START sort by ", COLOR, "(this is all you need once the Iterator is defined)")
+	fmt.Fprintln(w, "type "+APPLE+COLOR+" []*"+APPLE+"")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "func (a "+APPLE+COLOR+") Len() int           { return len(a) }")
+	fmt.Fprintln(w, "func (a "+APPLE+COLOR+") Less(i, j int) bool { return a[i]."+COLOR+" < a[j]."+COLOR+" }")
+	fmt.Fprintln(w, "func (a "+APPLE+COLOR+") Swap(i, j int)      { a[i], a[j] = a[j], a[i] }")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "func (x *"+FRUIT+") SortBy"+COLOR+"() *"+APPLE+"Iterator {")
+	fmt.Fprintln(w, "	things := x.all()")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "	sort.Sort("+APPLE+COLOR+"(things))")
+	fmt.Fprintln(w, "")
+	fmt.Fprintln(w, "	iterator := New"+APPLE+"Iterator(things)")
+	fmt.Fprintln(w, "	return iterator")
+	fmt.Fprintln(w, "}")
+	fmt.Fprintln(w, "// END sort by", COLOR)
+}