// ingestion/internal/pipeline/pipeline_test.go
package pipeline

import (
	"context"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"github.com/mathiasbq/hyperguild/ingestion/internal/llm"
	"github.com/mathiasbq/hyperguild/ingestion/internal/wiki"
)

func TestRun_WritesPages(t *testing.T) {
	brainDir := t.TempDir()
	for _, sub := range []string{"wiki/concepts", "wiki/entities", "wiki/sources"} {
		require.NoError(t, os.MkdirAll(filepath.Join(brainDir, sub), 0o755))
	}

	llmResponse := mustJSON([]wiki.Page{
		{
			Path:    "wiki/sources/test-article.md",
			Content: "---\ntitle: Test Article\ntype: article\ndomain: software-engineering\ndate_ingested: 2026-04-22\nlast_updated: 2026-04-22\naliases:\n  - Test Article\n---\n\n## Summary\n\nA test article.\n\n## Key Claims\n\n- It tests things.\n\n## Concepts Introduced or Reinforced\n\n## Entities Mentioned\n\n## Open Questions Raised\n",
		},
		{
			Path:    "wiki/concepts/testing.md",
			Content: "---\ntitle: Testing\ndomain: software-engineering\nlast_updated: 2026-04-22\naliases:\n  - Testing\n---\n\n## Definition\n\nThe practice of verifying software.\n\n## Why It Matters\n\nCatches bugs.\n\n## Related Concepts\n\n## Related Entities\n\n## Sources\n\n## Evolving Notes\n",
		},
	})

	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		_ = json.NewEncoder(w).Encode(map[string]any{
			"choices": []map[string]any{
				{"message": map[string]any{"role": "assistant", "content": llmResponse}},
			},
		})
	}))
	defer srv.Close()

	cfg := Config{
		Complete:  llm.New(srv.URL, "", "test-model", 30*time.Second).Complete,
		ChunkSize: 0,
	}

	result, err := Run(context.Background(), cfg, brainDir, "An article about testing.", "test-article", false)
	require.NoError(t, err)
	assert.Len(t, result.Pages, 2)
	assert.Empty(t, result.Warnings)

	_, err = os.Stat(filepath.Join(brainDir, "wiki", "sources", "test-article.md"))
	require.NoError(t, err)
	_, err = os.Stat(filepath.Join(brainDir, "wiki", "concepts", "testing.md"))
	require.NoError(t, err)
	_, err = os.Stat(filepath.Join(brainDir, "wiki", "index.md"))
	require.NoError(t, err)
	_, err = os.Stat(filepath.Join(brainDir, "log.md"))
	require.NoError(t, err)
}

func TestRun_DryRunDoesNotWrite(t *testing.T) {
	brainDir := t.TempDir()
	for _, sub := range []string{"wiki/concepts", "wiki/entities", "wiki/sources"} {
		require.NoError(t, os.MkdirAll(filepath.Join(brainDir, sub), 0o755))
	}

	llmResponse := mustJSON([]wiki.Page{{
		Path:    "wiki/sources/foo.md",
		Content: "---\ntitle: Foo\n---\n\n## Summary\n\nFoo.\n",
	}})

	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		_ = json.NewEncoder(w).Encode(map[string]any{
			"choices": []map[string]any{{"message": map[string]any{"content": llmResponse}}},
		})
	}))
	defer srv.Close()

	cfg := Config{Complete: llm.New(srv.URL, "", "m", 30*time.Second).Complete}
	result, err := Run(context.Background(), cfg, brainDir, "foo content", "foo", true)
	require.NoError(t, err)
	assert.Len(t, result.Pages, 1)

	_, err = os.Stat(filepath.Join(brainDir, "wiki", "sources", "foo.md"))
	assert.True(t, os.IsNotExist(err))
}

func TestRun_MergesDuplicatePaths(t *testing.T) {
	brainDir := t.TempDir()
	for _, sub := range []string{"wiki/concepts", "wiki/entities", "wiki/sources"} {
		require.NoError(t, os.MkdirAll(filepath.Join(brainDir, sub), 0o755))
	}

	// LLM returns same path twice (simulates multi-chunk merge)
	llmResponse := mustJSON([]wiki.Page{
		{Path: "wiki/concepts/foo.md", Content: "---\ntitle: Foo\n---\n\n## Definition\n\nFirst.\n\n## Related Concepts\n\n- [[bar|Bar]]\n"},
		{Path: "wiki/concepts/foo.md", Content: "---\ntitle: Foo\n---\n\n## Definition\n\nSecond.\n\n## Related Concepts\n\n- [[baz|Baz]]\n"},
	})

	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		_ = json.NewEncoder(w).Encode(map[string]any{
			"choices": []map[string]any{{"message": map[string]any{"content": llmResponse}}},
		})
	}))
	defer srv.Close()

	cfg := Config{Complete: llm.New(srv.URL, "", "m", 30*time.Second).Complete}
	result, err := Run(context.Background(), cfg, brainDir, "content", "foo", false)
	require.NoError(t, err)
	assert.Len(t, result.Pages, 1) // deduplicated

	content, err := os.ReadFile(filepath.Join(brainDir, "wiki", "concepts", "foo.md"))
	require.NoError(t, err)
	// keep-first for Definition, union for Related Concepts
	assert.Contains(t, string(content), "First.")
	assert.Contains(t, string(content), "[[bar|Bar]]")
	assert.Contains(t, string(content), "[[baz|Baz]]")
}

func mustJSON(v any) string {
	b, err := json.Marshal(v)
	if err != nil {
		panic(err)
	}
	return string(b)
}