package gateway

import (
	"context"
	"encoding/json"
	"sort"
	"strings"
	"testing"
	"time"

	"github.com/gorilla/websocket"

	"git.yeij.top/AskaEth/Cyrene_v2/internal/auth"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/trace"
)

// These tests cover the only leg of the design/19 flow chain that had no test:
// the producer's bus event → hub relay → outbound WS frame. The loop side is
// pinned by internal/runtime/loop/flow_test.go; this pins the gateway relay AND
// the wire field names the frontend's parseGraph reads, so a rename on either side
// fails here instead of silently blanking the 全链路流程 page.

// TestFlowGraphUpdateRelayedToWS publishes a real trace.RunGraph snapshot on the
// producer subject (ws.graph_update) and asserts the client receives a
// `graph_update` frame carrying the snapshot unchanged.
func TestFlowGraphUpdateRelayedToWS(t *testing.T) {
	env := newEnv(t, nil, false)
	tok := env.token(t, auth.RoleOwner)
	wsURL := "ws" + strings.TrimPrefix(env.ts.URL, "http") + "/ws/chat?token=" + tok

	conn, _, err := websocket.DefaultDialer.Dial(wsURL, nil)
	if err != nil {
		t.Fatalf("dial: %v", err)
	}
	defer conn.Close()
	_ = conn.SetReadDeadline(time.Now().Add(3 * time.Second))

	// Round-trip a mode_switch first so the connection is registered before the
	// publish (same guard as TestWSUpgradeAndBroadcast).
	if err := conn.WriteJSON(wsInbound{Type: "mode_switch", Data: json.RawMessage(`{"mode":"chat"}`)}); err != nil {
		t.Fatalf("write mode_switch: %v", err)
	}
	if got := readWS(t, conn); got.Type != "mode_switch" {
		t.Fatalf("first frame type = %q, want mode_switch", got.Type)
	}

	snap := sampleFlowSnapshot()
	if err := env.bus.Publish(context.Background(), "ws.graph_update", snap); err != nil {
		t.Fatalf("publish graph: %v", err)
	}
	raw := readRawWS(t, conn)

	var frame struct {
		Type string          `json:"type"`
		Data json.RawMessage `json:"data"`
	}
	if err := json.Unmarshal(raw, &frame); err != nil {
		t.Fatalf("decode frame %s: %v", raw, err)
	}
	if frame.Type != "graph_update" {
		t.Fatalf("frame type = %q, want graph_update (frame=%s)", frame.Type, raw)
	}

	// The relayed payload must be the snapshot verbatim — same JSON, not re-shaped.
	want, err := json.Marshal(snap)
	if err != nil {
		t.Fatalf("marshal snapshot: %v", err)
	}
	if string(frame.Data) != string(want) {
		t.Fatalf("relayed data differs from the published snapshot:\n got %s\nwant %s", frame.Data, want)
	}
}

// TestFlowGraphUpdateWireFields pins the JSON key names on every level of the
// snapshot against the fields the frontend reader (parseGraph in lib/wsParse.ts)
// requires. It is deliberately an exact key-set comparison: adding, renaming or
// dropping a field the frontend reads must fail here.
func TestFlowGraphUpdateWireFields(t *testing.T) {
	raw, err := json.Marshal(sampleFlowSnapshot())
	if err != nil {
		t.Fatalf("marshal snapshot: %v", err)
	}
	var graph map[string]json.RawMessage
	if err := json.Unmarshal(raw, &graph); err != nil {
		t.Fatalf("decode graph: %v", err)
	}

	assertGraphKeys(t, graph)
	nodes := decodeObjects(t, graph["nodes"], "nodes")
	assertNodeKeys(t, nodes)
	assertEdgeKeys(t, decodeObjects(t, graph["edges"], "edges"))
	assertLogKeys(t, nodes)
	assertGraphMeta(t, raw)
}

// assertGraphKeys pins the top-level FlowGraph keys read by parseGraph/Flow.tsx.
func assertGraphKeys(t *testing.T, graph map[string]json.RawMessage) {
	t.Helper()
	want := []string{"id", "nodes", "edges", "sessionId", "startedAt", "endedAt"}
	if got := sortedKeys(graph); !equalKeys(got, want) {
		t.Fatalf("graph keys = %v, want %v", got, want)
	}
}

// assertNodeKeys checks every emitted node key is one the frontend reads, that each
// node carries the always-read id/label, and that the node holding props+log has
// the complete set (which pins the omitempty tags too).
func assertNodeKeys(t *testing.T, nodes []map[string]json.RawMessage) {
	t.Helper()
	want := []string{"id", "label", "kind", "status", "startedAt", "endedAt", "props", "log"}
	fullSeen := false
	for i, n := range nodes {
		keys := sortedKeys(n)
		for _, k := range keys {
			if !containsKey(want, k) {
				t.Fatalf("node[%d] has unexpected key %q; frontend reads %v", i, k, want)
			}
		}
		if !containsKey(keys, "id") || !containsKey(keys, "label") {
			t.Fatalf("node[%d] keys = %v, must contain id and label", i, keys)
		}
		if containsKey(keys, "props") && containsKey(keys, "log") {
			fullSeen = true
			if !equalKeys(keys, want) {
				t.Fatalf("node[%d] keys = %v, want the full set %v", i, keys, want)
			}
		}
	}
	if !fullSeen {
		t.Fatal("no node carried both props and log; the omitempty tags are unpinned")
	}
}

// assertEdgeKeys pins the FlowEdge shape (parseGraph reads from/to).
func assertEdgeKeys(t *testing.T, edges []map[string]json.RawMessage) {
	t.Helper()
	if len(edges) == 0 {
		t.Fatal("snapshot has no edges")
	}
	for i, e := range edges {
		if got := sortedKeys(e); !equalKeys(got, []string{"from", "to"}) {
			t.Fatalf("edge[%d] keys = %v, want [from to]", i, got)
		}
	}
}

// assertLogKeys pins a node's log entry shape (parseGraph reads time/type/props).
func assertLogKeys(t *testing.T, nodes []map[string]json.RawMessage) {
	t.Helper()
	var logged []map[string]json.RawMessage
	for _, n := range nodes {
		rawLog, ok := n["log"]
		if !ok {
			continue
		}
		if err := json.Unmarshal(rawLog, &logged); err != nil {
			t.Fatalf("decode log: %v", err)
		}
	}
	if len(logged) == 0 {
		t.Fatal("snapshot has no log entries to pin")
	}
	for i, ev := range logged {
		if got := sortedKeys(ev); !equalKeys(got, []string{"time", "type", "props"}) {
			t.Fatalf("log[%d] keys = %v, want [props time type]", i, got)
		}
	}
}

// assertGraphMeta pins the envelope values the frontend renders (graph id/session
// pair) and that timestamps arrive as RFC3339Nano (what Date.parse expects).
func assertGraphMeta(t *testing.T, raw []byte) {
	t.Helper()
	var meta struct {
		ID        string `json:"id"`
		SessionID string `json:"sessionId"`
		StartedAt string `json:"startedAt"`
	}
	if err := json.Unmarshal(raw, &meta); err != nil {
		t.Fatalf("decode meta: %v", err)
	}
	if meta.ID != "web-1" || meta.SessionID != "web" {
		t.Fatalf("graph id/sessionId = %q/%q, want web-1/web", meta.ID, meta.SessionID)
	}
	if _, err := time.Parse(time.RFC3339Nano, meta.StartedAt); err != nil {
		t.Fatalf("startedAt %q is not RFC3339Nano: %v", meta.StartedAt, err)
	}
}

// sampleFlowSnapshot builds a real producer-side snapshot (trace.RunGraph, the same
// type the loop's FlowPublisher publishes) whose every optional wire field is
// populated, so the key-set assertions above are meaningful.
func sampleFlowSnapshot() *trace.FlowGraph {
	base := time.Date(2026, 10, 3, 21, 0, 0, 0, time.UTC)
	g := trace.NewRunGraph("web")
	g.Start(1, base)
	g.SeedInput("帮我查一下天气")
	g.AddSpanStart("span-llm", "llm.call", trace.SpanKindLLM, "", base.Add(time.Millisecond))
	g.AddSpan(trace.SpanRecord{
		ID:        "span-llm",
		Name:      "llm.call",
		Kind:      trace.SpanKindLLM,
		Status:    trace.SpanStatusOK,
		StartedAt: base.Add(time.Millisecond),
		EndedAt:   base.Add(20 * time.Millisecond),
		Props:     map[string]any{"stop_reason": "tool_calls", "step": 1},
		Events:    []trace.Event{{Time: base.Add(2 * time.Millisecond), Type: "llm.done", Props: map[string]any{"tools": 1}}},
	})
	g.AddSpanStart("span-tool", "tool.get_weather", trace.SpanKindTool, "span-llm", base.Add(21*time.Millisecond))
	g.AddSpan(trace.SpanRecord{
		ID:        "span-tool",
		ParentID:  "span-llm",
		Name:      "tool.get_weather",
		Kind:      trace.SpanKindTool,
		Status:    trace.SpanStatusOK,
		StartedAt: base.Add(21 * time.Millisecond),
		EndedAt:   base.Add(30 * time.Millisecond),
		Props:     map[string]any{"tool": "get_weather", "result": "晴 26℃"},
		Events:    []trace.Event{{Time: base.Add(25 * time.Millisecond), Type: "tool.done", Props: map[string]any{"ok": true}}},
	})
	g.SeedOutput("今天晴，26 度。")
	return g.Snapshot()
}

// decodeObjects decodes a raw JSON array of objects, failing on a malformed shape.
func decodeObjects(t *testing.T, raw json.RawMessage, what string) []map[string]json.RawMessage {
	t.Helper()
	var out []map[string]json.RawMessage
	if err := json.Unmarshal(raw, &out); err != nil {
		t.Fatalf("decode %s: %v", what, err)
	}
	if len(out) == 0 {
		t.Fatalf("snapshot has no %s", what)
	}
	return out
}

// readRawWS reads one text frame and returns its raw bytes.
func readRawWS(t *testing.T, conn *websocket.Conn) []byte {
	t.Helper()
	_, msg, err := conn.ReadMessage()
	if err != nil {
		t.Fatalf("read ws: %v", err)
	}
	return msg
}

// sortedKeys returns the object's JSON keys in sorted order.
func sortedKeys(obj map[string]json.RawMessage) []string {
	out := make([]string, 0, len(obj))
	for k := range obj {
		out = append(out, k)
	}
	sort.Strings(out)
	return out
}

// equalKeys reports whether got has exactly the members of want (both sorted).
func equalKeys(got []string, want []string) bool {
	want = append([]string(nil), want...)
	sort.Strings(want)
	if len(got) != len(want) {
		return false
	}
	for i := range got {
		if got[i] != want[i] {
			return false
		}
	}
	return true
}

// containsKey reports whether the (sorted) key list holds k.
func containsKey(keys []string, k string) bool {
	for _, key := range keys {
		if key == k {
			return true
		}
	}
	return false
}