package platform

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
)

func TestEnsureBlockInsertsIntoMissingFile(t *testing.T) {
	dir := t.TempDir()
	p := filepath.Join(dir, "rc")
	if err := EnsureBlock(p, "archduino", "export FOO=1"); err != nil {
		t.Fatal(err)
	}
	got, _ := os.ReadFile(p)
	want := "# >>> archduino >>>\nexport FOO=1\n# <<< archduino <<<\n"
	if string(got) != want {
		t.Fatalf("got %q want %q", got, want)
	}
}

func TestEnsureBlockReplacesExisting(t *testing.T) {
	dir := t.TempDir()
	p := filepath.Join(dir, "rc")
	initial := "alias ll='ls -l'\n# >>> archduino >>>\nold content\n# <<< archduino <<<\necho tail\n"
	if err := os.WriteFile(p, []byte(initial), 0o644); err != nil {
		t.Fatal(err)
	}
	if err := EnsureBlock(p, "archduino", "new content"); err != nil {
		t.Fatal(err)
	}
	got, _ := os.ReadFile(p)
	want := "alias ll='ls -l'\n# >>> archduino >>>\nnew content\n# <<< archduino <<<\necho tail\n"
	if string(got) != want {
		t.Fatalf("got %q want %q", got, want)
	}
}

func TestEnsureBlockIdempotent(t *testing.T) {
	dir := t.TempDir()
	p := filepath.Join(dir, "rc")
	_ = EnsureBlock(p, "a", "x")
	before, _ := os.ReadFile(p)
	_ = EnsureBlock(p, "a", "x")
	after, _ := os.ReadFile(p)
	if string(before) != string(after) {
		t.Fatalf("not idempotent: %q vs %q", before, after)
	}
}

func TestHasBlockTrueFalse(t *testing.T) {
	dir := t.TempDir()
	p := filepath.Join(dir, "rc")
	has, err := HasBlock(p, "a")
	if err != nil {
		t.Fatal(err)
	}
	if has {
		t.Fatal("missing file should report has=false")
	}
	_ = os.WriteFile(p, []byte("no blocks here\n"), 0o644)
	has, _ = HasBlock(p, "a")
	if has {
		t.Fatal("unblocked file should report has=false")
	}
	_ = EnsureBlock(p, "a", "x")
	has, _ = HasBlock(p, "a")
	if !has {
		t.Fatal("blocked file should report has=true")
	}
}

func TestRemoveBlock(t *testing.T) {
	dir := t.TempDir()
	p := filepath.Join(dir, "rc")
	_ = os.WriteFile(p, []byte("head\n# >>> a >>>\nmid\n# <<< a <<<\ntail\n"), 0o644)
	if err := RemoveBlock(p, "a"); err != nil {
		t.Fatal(err)
	}
	got, _ := os.ReadFile(p)
	if strings.Contains(string(got), ">>> a >>>") {
		t.Fatalf("block not removed: %q", got)
	}
	if !strings.Contains(string(got), "head") || !strings.Contains(string(got), "tail") {
		t.Fatalf("surrounding content lost: %q", got)
	}
}