package config

import (
	"strings"
	"testing"
)

func TestParseTOML(t *testing.T) {
	tests := []struct {
		name    string
		in      string
		want    map[string]any // dotted paths -> expected values
		wantErr string
	}{
		{
			name: "scalars and comments",
			in:   "# top\nlisten = \"127.0.0.1:8082\" # inline\nflag = true\nnum = 42\n",
			want: map[string]any{"listen": "127.0.0.1:8082", "flag": true, "num": int64(42)},
		},
		{
			name: "tables with quoted dotted keys",
			in:   "[refs.\"mpk-redmine\"]\nbackend = \"file\"\n\n[refs.\"mpk-env\"]\nbackend = \"env\"\n",
			want: map[string]any{"refs.mpk-redmine.backend": "file", "refs.mpk-env.backend": "env"},
		},
		{
			name: "escapes in basic strings",
			in:   "a = \"x\\ty\\\"z\"\n",
			want: map[string]any{"a": "x\ty\"z"},
		},
		{
			name: "literal strings keep backslashes",
			in:   "a = 'C:\\path'\n",
			want: map[string]any{"a": `C:\path`},
		},
		{
			name:    "duplicate key",
			in:      "a = \"1\"\na = \"2\"\n",
			wantErr: "duplicate key",
		},
		{
			name:    "unterminated string",
			in:      "a = \"oops\n",
			wantErr: "unterminated string",
		},
		{
			name:    "unsupported richer syntax fails loudly",
			in:      "a = [\"x\", \"y\"]\n",
			wantErr: "unsupported value",
		},
		{
			name:    "malformed table header",
			in:      "[refs\n",
			wantErr: "malformed table header",
		},
		{
			name:    "bare line without equals",
			in:      "garbage\n",
			wantErr: "expected key = value",
		},
		{
			name:    "table conflicts with scalar",
			in:      "refs = \"x\"\n[refs.\"mpk-a\"]\nbackend = \"file\"\n",
			wantErr: "conflicts",
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			doc, err := parseTOML([]byte(tt.in))
			if tt.wantErr != "" {
				if err == nil {
					t.Fatalf("want error %q, got doc %v", tt.wantErr, doc)
				}
				if !strings.Contains(err.Error(), tt.wantErr) {
					t.Fatalf("error %q does not contain %q", err, tt.wantErr)
				}
				return
			}
			if err != nil {
				t.Fatalf("unexpected error: %v", err)
			}
			for path, want := range tt.want {
				segs := strings.Split(path, ".")
				cur := any(doc)
				for _, seg := range segs {
					m, ok := cur.(Doc)
					if !ok {
						t.Fatalf("path %s: %v is not a table", path, cur)
					}
					cur = m[seg]
				}
				if cur != want {
					t.Fatalf("path %s: got %#v, want %#v", path, cur, want)
				}
			}
		})
	}
}