Massive architectural rework

This commit massively overhauls the project's structure to simplify
development. Most parts are now correctly compartmentalized and
dependencies are passed in a sane way rather than global variables
galore xd.

internal/util/cli/spinner.go

@@ -0,0 +1,72 @@
+package cli_util
+
+import (
+	"fmt"
+	"os"
+	"sync"
+)
+
+type CustomSpinnerWriter struct {
+	currentSpinnerMsg string
+	lock              sync.Mutex
+}
+
+func NewCustomSpinnerWriter() *CustomSpinnerWriter {
+	return &CustomSpinnerWriter{
+		currentSpinnerMsg: "",
+		lock:              sync.Mutex{},
+	}
+}
+
+func (w *CustomSpinnerWriter) Write(p []byte) (n int, err error) {
+	w.lock.Lock()
+	defer w.lock.Unlock()
+
+	n, err = os.Stdout.Write(p)
+	if err != nil {
+		return n, err
+	}
+
+	w.currentSpinnerMsg = string(p)
+
+	return len(p), nil
+}
+
+type CustomStdout struct {
+	spinner *CustomSpinnerWriter
+	lock    sync.Mutex
+}
+
+func NewCustomStdout(spinner *CustomSpinnerWriter) *CustomStdout {
+	return &CustomStdout{
+		spinner: spinner,
+		lock:    sync.Mutex{},
+	}
+}
+
+// We have this custom writer because we want to have a spinner at the bottom of the terminal, but we dont want to have
+// it interfere with the output of the command
+func (w *CustomStdout) Write(p []byte) (n int, err error) {
+	w.lock.Lock()
+	defer w.lock.Unlock()
+
+	// clear line and carriage return
+	n, err = os.Stdout.Write(fmt.Appendf(nil, "\033[2K\r%s", p))
+	if err != nil {
+		return n, err
+	}
+
+	nn, err := os.Stdout.Write([]byte(w.spinner.currentSpinnerMsg))
+	if err != nil {
+		return n, err
+	}
+
+	n = nn + n
+
+	return n, nil
+}
+
+func (w *CustomStdout) Printf(format string, a ...interface{}) (n int, err error) {
+	str := fmt.Sprintf(format, a...)
+	return w.Write([]byte(str))
+}