package git

import (
	"context"
	"errors"
	"strings"
	"testing"
)

func TestParseSymrefHead(t *testing.T) {
	tests := []struct {
		name    string
		output  string
		want    string
		wantErr string
	}{
		{
			name:   "symref line followed by the hash line",
			output: "ref: refs/heads/main\tHEAD\n1a2b3c4d5e6f\tHEAD\n",
			want:   "main",
		},
		{
			name:   "branch with a slash",
			output: "ref: refs/heads/feature/one\tHEAD\n1a2b3c\tHEAD\n",
			want:   "feature/one",
		},
		{
			name:    "detached head answers only a hash",
			output:  "1a2b3c4d5e6f\tHEAD\n",
			wantErr: "no symref for HEAD",
		},
		{
			name:    "head pointing at a tag is not a default branch",
			output:  "ref: refs/tags/v1.0\tHEAD\n1a2b3c\tHEAD\n",
			wantErr: "does not point at a branch",
		},
		{
			name:    "symref for another ref is ignored",
			output:  "ref: refs/heads/other\trefs/remotes/origin/main\n1a2b3c\tHEAD\n",
			wantErr: "no symref for HEAD",
		},
		{
			name:    "empty output",
			output:  "",
			wantErr: "no symref for HEAD",
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got, err := ParseSymrefHead(tt.output)
			if tt.wantErr != "" {
				if err == nil || !strings.Contains(err.Error(), tt.wantErr) {
					t.Fatalf("ParseSymrefHead(%q) = %q, %v; want error containing %q", tt.output, got, err, tt.wantErr)
				}
				return
			}
			if err != nil {
				t.Fatalf("ParseSymrefHead(%q): %v", tt.output, err)
			}
			if got != tt.want {
				t.Fatalf("ParseSymrefHead(%q) = %q, want %q", tt.output, got, tt.want)
			}
		})
	}
}

type errRunner struct{}

func (errRunner) Run(context.Context, string, []string, string, ...string) (string, error) {
	return "fatal: could not read from remote repository", errors.New("command git failed: exit status 128")
}
func (errRunner) LookPath(string) (string, error) { return "/usr/bin/git", nil }

func TestRemoteHeadWrapsTheGitFailure(t *testing.T) {
	_, err := RemoteHead(context.Background(), errRunner{}, "/home", "", "https://example.com/a/b.git")
	if err == nil || !strings.Contains(err.Error(), "ls-remote") {
		t.Fatalf("RemoteHead error = %v, want it wrapped as ls-remote", err)
	}
}

type captureRunner struct{ env []string }

func (c *captureRunner) Run(_ context.Context, _ string, env []string, _ string, _ ...string) (string, error) {
	c.env = env
	return "ref: refs/heads/main\tHEAD\n1a2b3c\tHEAD\n", nil
}
func (c *captureRunner) LookPath(string) (string, error) { return "/usr/bin/git", nil }

func TestRemoteHeadSendsTheSourceThroughTheConnectProxy(t *testing.T) {
	runner := &captureRunner{}
	got, err := RemoteHead(context.Background(), runner, "/home", "127.0.0.1:9", "https://example.com/a/b.git")
	if err != nil {
		t.Fatalf("RemoteHead: %v", err)
	}
	if got != "main" {
		t.Fatalf("RemoteHead = %q, want main", got)
	}
	want := "HTTPS_PROXY=http://127.0.0.1:9"
	for _, entry := range runner.env {
		if entry == want {
			return
		}
	}
	t.Fatalf("describe ran without the connect proxy: env = %v, want %s", runner.env, want)
}