package kg

import (
	"context"
	"database/sql"
	"path/filepath"
	"testing"
	"time"

	"git.wntrmute.dev/kyle/exo/artifacts"
	"git.wntrmute.dev/kyle/exo/core"
	"git.wntrmute.dev/kyle/exo/db"
)

func mustOpenAndMigrate(t *testing.T) *sql.DB {
	t.Helper()
	path := filepath.Join(t.TempDir(), "test.db")
	database, err := db.Open(path)
	if err != nil {
		t.Fatalf("Open failed: %v", err)
	}
	t.Cleanup(func() { _ = database.Close() })
	if err := db.Migrate(database); err != nil {
		t.Fatalf("Migrate failed: %v", err)
	}
	return database
}

func mustTX(t *testing.T, database *sql.DB) (*sql.Tx, context.Context) {
	t.Helper()
	ctx := context.Background()
	tx, err := db.StartTX(ctx, database)
	if err != nil {
		t.Fatalf("StartTX failed: %v", err)
	}
	return tx, ctx
}

// --- Node tests ---

func TestNodeStoreAndGet(t *testing.T) {
	database := mustOpenAndMigrate(t)
	tx, ctx := mustTX(t, database)

	node := NewNode("TestNote", NodeTypeNote)
	if err := node.Store(ctx, tx); err != nil {
		t.Fatalf("Node.Store failed: %v", err)
	}

	got := &Node{ID: node.ID}
	if err := got.Get(ctx, tx); err != nil {
		t.Fatalf("Node.Get failed: %v", err)
	}

	if got.Name != "TestNote" {
		t.Fatalf("name mismatch: got %q", got.Name)
	}
	if got.Type != NodeTypeNote {
		t.Fatalf("type mismatch: got %q", got.Type)
	}

	if err := db.EndTX(tx, nil); err != nil {
		t.Fatalf("EndTX failed: %v", err)
	}
}

func TestNodeHierarchy(t *testing.T) {
	database := mustOpenAndMigrate(t)
	tx, ctx := mustTX(t, database)

	parent := NewNode("ParentNote", NodeTypeNote)
	if err := parent.Store(ctx, tx); err != nil {
		t.Fatalf("parent Store failed: %v", err)
	}

	child := NewNode("ChildNote", NodeTypeNote)
	child.ParentID = parent.ID
	if err := child.Store(ctx, tx); err != nil {
		t.Fatalf("child Store failed: %v", err)
	}

	// Retrieve parent and check children.
	gotParent := &Node{ID: parent.ID}
	if err := gotParent.Get(ctx, tx); err != nil {
		t.Fatalf("parent Get failed: %v", err)
	}
	if len(gotParent.Children) != 1 {
		t.Fatalf("expected 1 child, got %d", len(gotParent.Children))
	}
	if gotParent.Children[0] != child.ID {
		t.Fatalf("child ID mismatch: got %q", gotParent.Children[0])
	}

	// Retrieve child and check parent.
	gotChild := &Node{ID: child.ID}
	if err := gotChild.Get(ctx, tx); err != nil {
		t.Fatalf("child Get failed: %v", err)
	}
	if gotChild.ParentID != parent.ID {
		t.Fatalf("parent ID mismatch: got %q", gotChild.ParentID)
	}

	if err := db.EndTX(tx, nil); err != nil {
		t.Fatalf("EndTX failed: %v", err)
	}
}

func TestNodeWithTags(t *testing.T) {
	database := mustOpenAndMigrate(t)
	tx, ctx := mustTX(t, database)

	// Create tags first (shared pool).
	if err := artifacts.CreateTag(ctx, tx, "philosophy"); err != nil {
		t.Fatalf("CreateTag failed: %v", err)
	}

	node := NewNode("PhilosophyNote", NodeTypeNote)
	node.Tags["philosophy"] = true
	if err := node.Store(ctx, tx); err != nil {
		t.Fatalf("Node.Store failed: %v", err)
	}

	got := &Node{ID: node.ID}
	if err := got.Get(ctx, tx); err != nil {
		t.Fatalf("Node.Get failed: %v", err)
	}
	if !got.Tags["philosophy"] {
		t.Fatalf("tag not found: %v", got.Tags)
	}

	if err := db.EndTX(tx, nil); err != nil {
		t.Fatalf("EndTX failed: %v", err)
	}
}

func TestGetNodeByName(t *testing.T) {
	database := mustOpenAndMigrate(t)
	tx, ctx := mustTX(t, database)

	node := NewNode("FindMe", NodeTypeNote)
	if err := node.Store(ctx, tx); err != nil {
		t.Fatalf("Store failed: %v", err)
	}

	got, err := GetNodeByName(ctx, tx, "FindMe")
	if err != nil {
		t.Fatalf("GetNodeByName failed: %v", err)
	}
	if got == nil {
		t.Fatal("expected to find node")
	}
	if got.ID != node.ID {
		t.Fatalf("ID mismatch: got %q, want %q", got.ID, node.ID)
	}

	missing, err := GetNodeByName(ctx, tx, "NotHere")
	if err != nil {
		t.Fatalf("GetNodeByName failed: %v", err)
	}
	if missing != nil {
		t.Fatal("expected nil for missing node")
	}

	if err := db.EndTX(tx, nil); err != nil {
		t.Fatalf("EndTX failed: %v", err)
	}
}

// --- Cell tests ---

func TestCellStoreAndGet(t *testing.T) {
	database := mustOpenAndMigrate(t)
	tx, ctx := mustTX(t, database)

	node := NewNode("CellNote", NodeTypeNote)
	if err := node.Store(ctx, tx); err != nil {
		t.Fatalf("Node.Store failed: %v", err)
	}

	cell := NewCell(node.ID, CellTypeMarkdown, []byte("# Hello\nThis is a note."))
	if err := cell.Store(ctx, tx); err != nil {
		t.Fatalf("Cell.Store failed: %v", err)
	}

	got := &Cell{ID: cell.ID}
	if err := got.Get(ctx, tx); err != nil {
		t.Fatalf("Cell.Get failed: %v", err)
	}
	if got.NodeID != node.ID {
		t.Fatalf("node ID mismatch: got %q", got.NodeID)
	}
	if got.Type != CellTypeMarkdown {
		t.Fatalf("type mismatch: got %q", got.Type)
	}
	if string(got.Contents) != "# Hello\nThis is a note." {
		t.Fatalf("contents mismatch: got %q", got.Contents)
	}

	if err := db.EndTX(tx, nil); err != nil {
		t.Fatalf("EndTX failed: %v", err)
	}
}

func TestGetCellsForNode(t *testing.T) {
	database := mustOpenAndMigrate(t)
	tx, ctx := mustTX(t, database)

	node := NewNode("MultiCell", NodeTypeNote)
	if err := node.Store(ctx, tx); err != nil {
		t.Fatalf("Store failed: %v", err)
	}

	c1 := NewCell(node.ID, CellTypeMarkdown, []byte("First"))
	c1.Ordinal = 0
	c2 := NewCell(node.ID, CellTypeCode, []byte("fmt.Println()"))
	c2.Ordinal = 1
	c3 := NewCell(node.ID, CellTypeMarkdown, []byte("Last"))
	c3.Ordinal = 2

	for _, c := range []*Cell{c1, c2, c3} {
		if err := c.Store(ctx, tx); err != nil {
			t.Fatalf("Cell.Store failed: %v", err)
		}
	}

	cells, err := GetCellsForNode(ctx, tx, node.ID)
	if err != nil {
		t.Fatalf("GetCellsForNode failed: %v", err)
	}
	if len(cells) != 3 {
		t.Fatalf("expected 3 cells, got %d", len(cells))
	}
	if string(cells[0].Contents) != "First" {
		t.Fatalf("first cell content mismatch: %q", cells[0].Contents)
	}
	if cells[1].Type != CellTypeCode {
		t.Fatalf("second cell type mismatch: %q", cells[1].Type)
	}

	if err := db.EndTX(tx, nil); err != nil {
		t.Fatalf("EndTX failed: %v", err)
	}
}

// --- Fact tests ---

func TestFactStoreAndGet(t *testing.T) {
	database := mustOpenAndMigrate(t)
	tx, ctx := mustTX(t, database)

	entityID := core.NewUUID()
	attrID := core.NewUUID()

	fact := NewFact(entityID, "TestEntity", attrID, "color", core.Vals("blue"))
	if err := fact.Store(ctx, tx); err != nil {
		t.Fatalf("Fact.Store failed: %v", err)
	}

	facts, err := GetFactsForEntity(ctx, tx, entityID)
	if err != nil {
		t.Fatalf("GetFactsForEntity failed: %v", err)
	}
	if len(facts) != 1 {
		t.Fatalf("expected 1 fact, got %d", len(facts))
	}
	if facts[0].Value.Contents != "blue" {
		t.Fatalf("value mismatch: %q", facts[0].Value.Contents)
	}
	if facts[0].Retraction {
		t.Fatal("should not be a retraction")
	}

	if err := db.EndTX(tx, nil); err != nil {
		t.Fatalf("EndTX failed: %v", err)
	}
}

func TestFactRetraction(t *testing.T) {
	database := mustOpenAndMigrate(t)
	tx, ctx := mustTX(t, database)

	entityID := core.NewUUID()
	attrID := core.NewUUID()

	// Assert a fact.
	fact := NewFact(entityID, "Entity", attrID, "status", core.Vals("active"))
	if err := fact.Store(ctx, tx); err != nil {
		t.Fatalf("Store assertion failed: %v", err)
	}

	// Retract it.
	time.Sleep(10 * time.Millisecond) // ensure different timestamp
	retraction := fact.Retract()
	if err := retraction.Store(ctx, tx); err != nil {
		t.Fatalf("Store retraction failed: %v", err)
	}

	// All facts should include both.
	allFacts, err := GetFactsForEntity(ctx, tx, entityID)
	if err != nil {
		t.Fatalf("GetFactsForEntity failed: %v", err)
	}
	if len(allFacts) != 2 {
		t.Fatalf("expected 2 facts (assertion + retraction), got %d", len(allFacts))
	}

	// Current facts should be empty (retracted).
	current, err := GetCurrentFactsForEntity(ctx, tx, entityID)
	if err != nil {
		t.Fatalf("GetCurrentFactsForEntity failed: %v", err)
	}
	if len(current) != 0 {
		t.Fatalf("expected 0 current facts after retraction, got %d", len(current))
	}

	// Assert a new value.
	fact2 := NewFact(entityID, "Entity", attrID, "status", core.Vals("archived"))
	if err := fact2.Store(ctx, tx); err != nil {
		t.Fatalf("Store second assertion failed: %v", err)
	}

	current2, err := GetCurrentFactsForEntity(ctx, tx, entityID)
	if err != nil {
		t.Fatalf("GetCurrentFactsForEntity failed: %v", err)
	}
	if len(current2) != 1 {
		t.Fatalf("expected 1 current fact, got %d", len(current2))
	}
	if current2[0].Value.Contents != "archived" {
		t.Fatalf("expected 'archived', got %q", current2[0].Value.Contents)
	}

	if err := db.EndTX(tx, nil); err != nil {
		t.Fatalf("EndTX failed: %v", err)
	}
}

// --- Edge tests ---

func TestEdgeStoreAndGet(t *testing.T) {
	database := mustOpenAndMigrate(t)
	tx, ctx := mustTX(t, database)

	n1 := NewNode("Source", NodeTypeNote)
	n2 := NewNode("Target", NodeTypeNote)
	if err := n1.Store(ctx, tx); err != nil {
		t.Fatalf("Store n1 failed: %v", err)
	}
	if err := n2.Store(ctx, tx); err != nil {
		t.Fatalf("Store n2 failed: %v", err)
	}

	edge := NewEdge(n1.ID, n2.ID, EdgeRelationRelated)
	if err := edge.Store(ctx, tx); err != nil {
		t.Fatalf("Edge.Store failed: %v", err)
	}

	// Get edges from source.
	fromEdges, err := GetEdgesFrom(ctx, tx, n1.ID)
	if err != nil {
		t.Fatalf("GetEdgesFrom failed: %v", err)
	}
	if len(fromEdges) != 1 {
		t.Fatalf("expected 1 edge from source, got %d", len(fromEdges))
	}
	if fromEdges[0].TargetID != n2.ID {
		t.Fatalf("target mismatch: got %q", fromEdges[0].TargetID)
	}
	if fromEdges[0].Relation != EdgeRelationRelated {
		t.Fatalf("relation mismatch: got %q", fromEdges[0].Relation)
	}

	// Get edges to target.
	toEdges, err := GetEdgesTo(ctx, tx, n2.ID)
	if err != nil {
		t.Fatalf("GetEdgesTo failed: %v", err)
	}
	if len(toEdges) != 1 {
		t.Fatalf("expected 1 edge to target, got %d", len(toEdges))
	}

	if err := db.EndTX(tx, nil); err != nil {
		t.Fatalf("EndTX failed: %v", err)
	}
}

func TestNodeToArtifactLink(t *testing.T) {
	database := mustOpenAndMigrate(t)
	tx, ctx := mustTX(t, database)

	node := NewNode("Research", NodeTypeNote)
	if err := node.Store(ctx, tx); err != nil {
		t.Fatalf("Store failed: %v", err)
	}

	// Link to an artifact ID (doesn't need to exist in edges table).
	artifactID := core.NewUUID()
	edge := NewEdge(node.ID, artifactID, EdgeRelationArtifactLink)
	if err := edge.Store(ctx, tx); err != nil {
		t.Fatalf("Edge.Store failed: %v", err)
	}

	edges, err := GetEdgesFrom(ctx, tx, node.ID)
	if err != nil {
		t.Fatalf("GetEdgesFrom failed: %v", err)
	}
	if len(edges) != 1 {
		t.Fatalf("expected 1 edge, got %d", len(edges))
	}
	if edges[0].Relation != EdgeRelationArtifactLink {
		t.Fatalf("relation should be artifact_link, got %q", edges[0].Relation)
	}

	if err := db.EndTX(tx, nil); err != nil {
		t.Fatalf("EndTX failed: %v", err)
	}
}