package brain_test

import (
	"testing"

	"github.com/mathiasbq/hyperguild/ingestion/internal/brain"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

// seedCorpus writes the two entries every linkcheck case resolves against.
func seedCorpus(t *testing.T, dir string) {
	t.Helper()
	seedNote(t, dir, "wiki/homelab/facts/real-entry.md",
		"---\nwing: homelab\nhall: facts\ntitle: 'Real entry'\n---\n\nbody.\n")
	seedNote(t, dir, "knowledge/legacy-entry.md",
		"---\ntitle: 'Legacy entry'\n---\n\nbody.\n")
}

func TestStripUnresolvedLinks(t *testing.T) {
	tests := []struct {
		name     string
		body     string
		want     string
		stripped []string
	}{
		{
			name: "bare slug that resolves is kept",
			body: "See [[real-entry]] for the rule.",
			want: "See [[real-entry]] for the rule.",
		},
		{
			name: "path-style target that resolves is kept",
			body: "See [[homelab/facts/real-entry]].",
			want: "See [[homelab/facts/real-entry]].",
		},
		{
			name: "knowledge/ entry resolves by bare slug",
			body: "See [[legacy-entry]].",
			want: "See [[legacy-entry]].",
		},
		{
			name:     "unresolvable target is unwrapped to plain text",
			body:     "Related: [[secret-hygiene]].",
			want:     "Related: secret-hygiene.",
			stripped: []string{"secret-hygiene"},
		},
		{
			name:     "unresolvable aliased target keeps its display text",
			body:     "Related: [[feedback_check_host_not_assume|check the host]].",
			want:     "Related: check the host.",
			stripped: []string{"feedback_check_host_not_assume"},
		},
		{
			name: "link inside a fenced code block is left alone",
			body: "Syntax:\n\n```\n[[wing/hall/slug]]\n```\n",
			want: "Syntax:\n\n```\n[[wing/hall/slug]]\n```\n",
		},
		{
			name: "link inside an inline code span is left alone",
			body: "Write `[[wing/hall/slug]]` to link.",
			want: "Write `[[wing/hall/slug]]` to link.",
		},
		{
			name:     "every unresolvable target is reported once, sorted",
			body:     "[[zeta-gap]] and [[alpha-gap]] and [[zeta-gap]] again.",
			want:     "zeta-gap and alpha-gap and zeta-gap again.",
			stripped: []string{"alpha-gap", "zeta-gap"},
		},
	}

	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			dir := t.TempDir()
			seedCorpus(t, dir)

			got, stripped, err := brain.StripUnresolvedLinks(dir, tc.body)
			require.NoError(t, err)
			assert.Equal(t, tc.want, got)
			assert.Equal(t, tc.stripped, stripped)
		})
	}
}

func TestStripUnresolvedLinks_MissingBrainDirIsNotAGate(t *testing.T) {
	// A brain dir with no knowledge//wiki/ tree yet must not turn every link
	// into an unresolved one — an empty corpus is a bootstrap state, not
	// evidence that the author invented the target.
	got, stripped, err := brain.StripUnresolvedLinks(t.TempDir(), "See [[real-entry]].")
	require.NoError(t, err)
	assert.Equal(t, "See [[real-entry]].", got)
	assert.Nil(t, stripped)
}