package backend

import (
	"strings"
	"testing"
)

func TestParseEnvFile(t *testing.T) {
	tests := []struct {
		name    string
		in      string
		want    map[string]string
		wantErr string
	}{
		{
			name: "simple lines",
			in:   "A=1\nB=two words\n",
			want: map[string]string{"A": "1", "B": "two words"},
		},
		{
			name: "comments and blanks",
			in:   "# header\n\nA=1\n   # indented comment\nB=2\n",
			want: map[string]string{"A": "1", "B": "2"},
		},
		{
			name: "export prefix",
			in:   "export A=1\nexport\tB=2\n",
			want: map[string]string{"A": "1", "B": "2"},
		},
		{
			name: "quoted values stripped",
			in:   "A=\"1 2\"\nB='3 4'\n",
			want: map[string]string{"A": "1 2", "B": "3 4"},
		},
		{
			name: "spaces around key and value trimmed",
			in:   "  A  =  1  \n",
			want: map[string]string{"A": "1"},
		},
		{
			name: "inline comment after value",
			in:   "A=1 # trailing\nB=\"2 # kept\"\n",
			want: map[string]string{"A": "1", "B": "2 # kept"},
		},
		{
			name: "equals inside value",
			in:   "A=b=c\n",
			want: map[string]string{"A": "b=c"},
		},
		{
			name: "crlf line endings",
			in:   "A=1\r\nB=2\r\n",
			want: map[string]string{"A": "1", "B": "2"},
		},
		{
			name: "later duplicate wins",
			in:   "A=first\nA=second\n",
			want: map[string]string{"A": "second"},
		},
		{
			name:    "line without equals",
			in:      "SECRET_MATERIAL_NO_EQUALS\n",
			wantErr: "line 1: malformed",
		},
		{
			name:    "illegal key character",
			in:      "A-B=supersecret\n",
			wantErr: "line 1: malformed",
		},
		{
			name:    "key starting with digit",
			in:      "1KEY=supersecret\n",
			wantErr: "line 1: malformed",
		},
		{
			name:    "empty key",
			in:      "=value\n",
			wantErr: "line 1: malformed",
		},
		{
			name:    "line number reported",
			in:      "A=1\nB=2\nbroken line here\n",
			wantErr: "line 3: malformed",
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got, err := parseEnvFile([]byte(tt.in))
			if tt.wantErr != "" {
				if err == nil {
					t.Fatalf("want error %q, got nil (parsed %v)", tt.wantErr, got)
				}
				if !strings.Contains(err.Error(), tt.wantErr) {
					t.Fatalf("error %q does not contain %q", err, tt.wantErr)
				}
				// Parse errors carry line numbers only — never line
				// contents (contents may be material).
				if strings.Contains(err.Error(), "supersecret") || strings.Contains(err.Error(), "SECRET_MATERIAL") {
					t.Fatalf("parse error leaks line contents: %q", err)
				}
				return
			}
			if err != nil {
				t.Fatalf("unexpected error: %v", err)
			}
			if len(got) != len(tt.want) {
				t.Fatalf("got %v, want %v", got, tt.want)
			}
			for k, v := range tt.want {
				if got[k] != v {
					t.Fatalf("key %s: got %q, want %q", k, got[k], v)
				}
			}
		})
	}
}