package main

import (
	"fmt"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"
)

// Both fixtures are the shapes the real files use: Claude Code writes one
// record per message with content blocks, codex wraps everything in a payload
// and keeps the model's history in response_items.
const claudeJSONL = `{"type":"user","timestamp":"2026-07-20T09:57:00.000Z","sessionId":"s1","cwd":"/repo","message":{"role":"user","content":"read lib.rs and tell me about the cache"}}
{"type":"assistant","timestamp":"2026-07-20T09:57:30.000Z","message":{"role":"assistant","model":"claude-opus-5","content":[{"type":"thinking","thinking":"start with the struct","signature":"CAIS"},{"type":"text","text":"Reading it now."},{"type":"tool_use","id":"toolu_1","name":"Bash","input":{"command":"vr read src/lib.rs:1-30","description":"read the file"}}]}}
{"type":"user","timestamp":"2026-07-20T09:59:10.000Z","message":{"role":"user","content":[{"type":"tool_result","tool_use_id":"toolu_1","content":"1\tuse std::collections::HashMap;\n2\t\n3\tstruct Cache;\n"}]}}
{"type":"mode","timestamp":"2026-07-20T09:59:11.000Z","mode":"default"}
{"type":"assistant","timestamp":"2026-07-20T09:59:40.000Z","message":{"role":"assistant","content":[{"type":"tool_use","id":"toolu_2","name":"Read","input":{"file_path":"/repo/src/main.rs"}}]}}
{"type":"user","timestamp":"2026-07-20T09:59:45.000Z","message":{"role":"user","content":[{"type":"tool_result","tool_use_id":"toolu_2","is_error":true,"content":[{"type":"text","text":"no such file"}]}]}}
{"type":"assistant","timestamp":"2026-07-20T10:02:30.000Z","message":{"role":"assistant","content":[{"type":"text","text":"It is a two-level map."}]}}
`

const codexJSONL = `{"timestamp":"2026-07-20T12:00:00.000Z","type":"session_meta","payload":{"id":"019f0000-0000-7000-8000-00000000abcd","cwd":"/repo"}}
{"timestamp":"2026-07-20T12:00:01.000Z","type":"response_item","payload":{"type":"message","role":"developer","content":[{"type":"input_text","text":"You are Codex, an agent."}]}}
{"timestamp":"2026-07-20T12:00:02.000Z","type":"response_item","payload":{"type":"message","role":"user","content":[{"type":"input_text","text":"<environment_context>\n  <cwd>/repo</cwd>\n</environment_context>"}]}}
{"timestamp":"2026-07-20T12:00:03.000Z","type":"response_item","payload":{"type":"message","role":"user","content":[{"type":"input_text","text":"review the cache"}]}}
{"timestamp":"2026-07-20T12:00:04.000Z","type":"response_item","payload":{"type":"reasoning","summary":[{"type":"summary_text","text":"start with lib.rs"}],"encrypted_content":"gAAAA"}}
{"timestamp":"2026-07-20T12:00:05.000Z","type":"response_item","payload":{"type":"function_call","name":"exec_command","call_id":"call_1","arguments":"{\"cmd\":\"vr read src/lib.rs\",\"workdir\":\"/repo\"}"}}
{"timestamp":"2026-07-20T12:00:06.000Z","type":"response_item","payload":{"type":"function_call_output","call_id":"call_1","output":"Chunk ID: abc123\nOutput:\n1\tstruct Cache;\n"}}
{"timestamp":"2026-07-20T12:00:07.000Z","type":"event_msg","payload":{"type":"agent_message","message":"the cache is two-level"}}
{"timestamp":"2026-07-20T12:00:08.000Z","type":"response_item","payload":{"type":"custom_tool_call","name":"apply_patch","call_id":"call_2","input":"*** Begin Patch\n*** Update File: src/lib.rs\n@@\n-old\n+new\n"}}
{"timestamp":"2026-07-20T12:00:09.000Z","type":"response_item","payload":{"type":"custom_tool_call_output","call_id":"call_2","output":"Exit code: 0\n"}}
{"timestamp":"2026-07-20T12:00:10.000Z","type":"response_item","payload":{"type":"message","role":"assistant","content":[{"type":"output_text","text":"The cache is two-level."}]}}
`

func writeFile(t *testing.T, path, body string) string {
	t.Helper()
	if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(path, []byte(body), 0o644); err != nil {
		t.Fatal(err)
	}
	return path
}

func turnLine(tn Turn) string {
	s := tn.Role
	if tn.Tool != "" {
		s += " " + tn.Tool
	}
	if tn.Text != "" {
		s += " " + tn.Text
	}
	if tn.Detail != "" {
		s += " " + tn.Detail
	}
	return s
}

func TestParseClaudeTranscript(t *testing.T) {
	path := writeFile(t, filepath.Join(t.TempDir(), "s.jsonl"), claudeJSONL)
	tr := readTranscript(path, int64(len(claudeJSONL)))
	if tr.Harness != "claude-code" || tr.Err != "" {
		t.Fatalf("harness = %q err = %q", tr.Harness, tr.Err)
	}
	want := []string{
		"user read lib.rs and tell me about the cache",
		"thinking start with the struct",
		"assistant Reading it now.",
		"tool Bash vr read src/lib.rs:1-30",
		"result Bash 1\tuse std::collections::HashMap; … +2 lines",
		"tool Read /repo/src/main.rs",
		"result Read no such file",
		"assistant It is a two-level map.",
	}
	var got []string
	for _, tn := range tr.Turns {
		got = append(got, turnLine(tn))
	}
	if strings.Join(got, "\n") != strings.Join(want, "\n") {
		t.Errorf("turns:\n%s\nwant:\n%s", strings.Join(got, "\n"), strings.Join(want, "\n"))
	}
	if tr.Turns[6].Kind != "error" {
		t.Error("a failed tool result is not marked")
	}
	if at := tr.Turns[0].When; at.Format(time.RFC3339) != "2026-07-20T09:57:00Z" {
		t.Errorf("first turn at %v", at)
	}
}

func TestParseCodexTranscript(t *testing.T) {
	path := writeFile(t, filepath.Join(t.TempDir(), "r.jsonl"), codexJSONL)
	tr := readTranscript(path, int64(len(codexJSONL)))
	if tr.Harness != "codex" || tr.Err != "" {
		t.Fatalf("harness = %q err = %q", tr.Harness, tr.Err)
	}
	want := []string{
		"user review the cache",
		"thinking start with lib.rs",
		"tool exec_command vr read src/lib.rs",
		"result exec_command Chunk ID: abc123 … +2 lines",
		"tool apply_patch *** Begin Patch … +4 lines",
		"result apply_patch Exit code: 0",
		"assistant The cache is two-level.",
	}
	var got []string
	for _, tn := range tr.Turns {
		got = append(got, turnLine(tn))
	}
	if strings.Join(got, "\n") != strings.Join(want, "\n") {
		t.Errorf("turns:\n%s\nwant:\n%s", strings.Join(got, "\n"), strings.Join(want, "\n"))
	}
}

// Tool output is what makes these files megabytes; a page gets one line of it.
func TestToolOutputIsSummarized(t *testing.T) {
	huge := strings.Repeat("x", 400) + "\n" + strings.Repeat("line\n", 50000)
	line := fmt.Sprintf(`{"type":"user","timestamp":"2026-07-20T10:00:00.000Z","message":{"role":"user","content":[{"type":"tool_result","tool_use_id":"t","content":%q}]}}`, huge)
	path := writeFile(t, filepath.Join(t.TempDir(), "big.jsonl"), line+"\n")
	tr := readTranscript(path, int64(len(line)+1))
	if len(tr.Turns) != 1 {
		t.Fatalf("turns = %d", len(tr.Turns))
	}
	if n := len(tr.Turns[0].Detail); n > 4*briefLine {
		t.Errorf("summary of a 250 KB result is %d bytes", n)
	}
	if !strings.Contains(tr.Turns[0].Detail, "+50000 lines") {
		t.Errorf("summary does not say what was left out: %q", tr.Turns[0].Detail)
	}
}

func TestTranscriptTooLargeIsRefused(t *testing.T) {
	path := writeFile(t, filepath.Join(t.TempDir(), "x.jsonl"), "{}\n")
	if tr := readTranscript(path, maxTranscript+1); !strings.Contains(tr.Err, "too large") {
		t.Errorf("err = %q", tr.Err)
	}
}

// ── locating ─────────────────────────────────────────────────────────────

func TestSafeSession(t *testing.T) {
	for _, ok := range []string{"s1", "web:goblin", "24983541-2e59-4d47-94bb-837acf8147c3",
		"019fa0f1-49de-7e33-af62-6db956589080"} {
		if err := safeSession(ok); err != nil {
			t.Errorf("safeSession(%q) = %v", ok, err)
		}
	}
	for _, bad := range []string{"", "..", "a/b", `a\b`, "../../etc/passwd", "a..b", "a b",
		"a*b", "a\x00b", strings.Repeat("x", 129)} {
		if err := safeSession(bad); err == nil {
			t.Errorf("safeSession(%q) was accepted", bad)
		}
	}
}

func TestFindTranscript(t *testing.T) {
	claudeRoot, codexRoot := t.TempDir(), t.TempDir()
	const (
		cid = "24983541-2e59-4d47-94bb-837acf8147c3"
		xid = "019fa0f1-49de-7e33-af62-6db956589080"
	)
	want := writeFile(t, filepath.Join(claudeRoot, "-home-u-0x4200-cafe-proj", cid+".jsonl"), claudeJSONL)
	wantX := writeFile(t, filepath.Join(codexRoot, "2026", "07", "26",
		"rollout-2026-07-26T21-19-55-"+xid+".jsonl"), codexJSONL)
	// a file outside every root must stay invisible
	outside := writeFile(t, filepath.Join(t.TempDir(), cid+".jsonl"), claudeJSONL)

	tx := newTranscripts([]string{claudeRoot, codexRoot})
	if got := tx.find(cid, "/home/u/0x4200.cafe/proj"); got != want {
		t.Errorf("with the logged cwd: %q, want %q", got, want)
	}
	if got := tx.find(cid, "/somewhere/else"); got != want {
		t.Errorf("with a stale cwd: %q, want %q", got, want)
	}
	if got := tx.find(xid, ""); got != wantX {
		t.Errorf("codex thread: %q, want %q", got, wantX)
	}
	if got := tx.find("nosuchsession", ""); got != "" {
		t.Errorf("unknown session found %q", got)
	}
	if got := newTranscripts(nil).find(cid, filepath.Dir(outside)); got != "" {
		t.Errorf("no roots configured, yet found %q", got)
	}
	if under(claudeRoot, outside) {
		t.Error("a path outside a root passed the check")
	}
}

// A 5 MB transcript is parsed once and then only re-read when it changes.
func TestTranscriptCacheKeyedByFile(t *testing.T) {
	root := t.TempDir()
	path := writeFile(t, filepath.Join(root, "-repo", "s1.jsonl"), claudeJSONL)
	tx := newTranscripts([]string{root})

	first := tx.load("s1", "/repo")
	if first == nil || len(first.Turns) == 0 {
		t.Fatal("nothing parsed")
	}
	if again := tx.load("s1", "/repo"); again != first {
		t.Error("an unchanged transcript was parsed twice")
	}
	writeFile(t, path, claudeJSONL+`{"type":"assistant","timestamp":"2026-07-20T11:00:00.000Z","message":{"role":"assistant","content":[{"type":"text","text":"one more thing"}]}}`+"\n")
	future := time.Now().Add(time.Second)
	os.Chtimes(path, future, future)
	after := tx.load("s1", "/repo")
	if after == first || len(after.Turns) != len(first.Turns)+1 {
		t.Errorf("a changed transcript was not re-parsed: %d -> %d turns", len(first.Turns), len(after.Turns))
	}
	if tx.load("nope", "/repo") != nil {
		t.Error("a missing transcript should be nil, not empty")
	}
}

// ── windowing ────────────────────────────────────────────────────────────

func TestConvWindowIsBounded(t *testing.T) {
	turns := make([]Turn, 500)
	for i := range turns {
		turns[i] = Turn{Role: "assistant", Text: fmt.Sprint(i)}
	}
	from, got := convWindowAt(turns, -1, false)
	if len(got) != convWindow || from != 500-convWindow || got[len(got)-1].Text != "499" {
		t.Errorf("unanchored window = %d turns from %d", len(got), from)
	}
	from, got = convWindowAt(turns, 200, false)
	if len(got) != convWindow || from > 200 || from+len(got) <= 200 {
		t.Errorf("window %d..%d does not hold turn 200", from, from+len(got))
	}
	from, got = convWindowAt(turns, 498, false)
	if len(got) != convWindow || from+len(got) != 500 {
		t.Errorf("window near the end = %d..%d", from, from+len(got))
	}
	if _, got = convWindowAt(turns, 200, true); len(got) != 500 {
		t.Errorf("show all gave %d of 500 turns", len(got))
	}
	if _, got = convWindowAt(turns[:10], -1, false); len(got) != 10 {
		t.Errorf("short conversation was cut to %d", len(got))
	}
}

// ── the session page ─────────────────────────────────────────────────────

// sessionServer is testServer with a Claude Code transcript for session s1,
// filed under the repo path the log entries carry.
func sessionServer(t *testing.T) (*server, string) {
	t.Helper()
	sv, _, _ := testServer(t)
	root := t.TempDir()
	writeFile(t, filepath.Join(root, mangleDir(sv.repo), "s1.jsonl"), claudeJSONL)
	sv.tx = newTranscripts([]string{root})
	return sv, root
}

func TestSessionPageInterleavesLogAndTranscript(t *testing.T) {
	sv, _ := sessionServer(t)
	body := get(t, sv.handler(), "/session/s1?note=1", false).Body.String()
	for _, want := range []string{
		"read lib.rs and tell me about the cache", // the conversation
		"It is a two-level map.",
		"vr read src/lib.rs:1-30",  // a tool call, summarized
		"read hello.txt:1-2",       // the vr log, woven in
		"second line matters",      // the note itself
		`data-anchor="note-1"`,     // and it is what the page lands on
		`class="turn t-note here"`, // marked as the anchored moment
	} {
		if !strings.Contains(body, want) {
			t.Errorf("session page is missing %q", want)
		}
	}
	// the whole file is never in the page
	if strings.Contains(body, "use std::collections::HashMap;\n2") {
		t.Error("a tool result was dumped in full")
	}
	// ordering: the note was logged after the first message, before the last
	iFirst := strings.Index(body, "read lib.rs and tell me")
	iNote := strings.Index(body, "second line matters")
	iLast := strings.Index(body, "It is a two-level map.")
	if !(iFirst < iNote && iNote < iLast) {
		t.Errorf("turns are out of order: %d %d %d", iFirst, iNote, iLast)
	}
}

func TestSessionPageWithoutATranscript(t *testing.T) {
	sv, _, _ := testServer(t)
	sv.tx = newTranscripts([]string{t.TempDir()})
	body := get(t, sv.handler(), "/session/s1", false).Body.String()
	if !strings.Contains(body, "no transcript found") {
		t.Error("the page does not say the transcript is missing")
	}
	if !strings.Contains(body, sv.tx.roots[0]) {
		t.Error("the page does not say where it looked")
	}
	if !strings.Contains(body, "read hello.txt:1-2") || !strings.Contains(body, "second line matters") {
		t.Error("the vr timeline is missing from the fallback")
	}
}

func TestSessionPageRejectsUnsafeIDs(t *testing.T) {
	sv, _ := sessionServer(t)
	h := sv.handler()
	if w := get(t, h, "/session/a%20b", false); w.Code != 400 {
		t.Errorf("GET /session/a b = %d, want 400", w.Code)
	}
	if w := get(t, h, "/session/unknown-session", false); w.Code != 200 ||
		!strings.Contains(w.Body.String(), "no transcript found") {
		t.Errorf("unknown session = %d", w.Code)
	}
}

// Live pages link a note to its conversation; the static export has no server
// to serve one from.
func TestConversationLinksAreLiveOnly(t *testing.T) {
	sv, _ := sessionServer(t)
	h := sv.handler()
	if b := get(t, h, "/notes", false).Body.String(); !strings.Contains(b, `href="/session/s1?note=1#note-1"`) {
		t.Error("no conversation link on a note card")
	}
	if b := get(t, h, "/", false).Body.String(); !strings.Contains(b, `href="/session/s1"`) {
		t.Error("the agents table does not link the session")
	}
	if b := get(t, h, "/activity", true).Body.String(); !strings.Contains(b, `href="/session/s1"`) {
		t.Error("the activity table does not link the session")
	}
	if b := get(t, h, "/session/s1?note=1", false).Body.String(); strings.Contains(b, ">conversation<") {
		t.Error("the session page links back to itself")
	}
	static := &page{Root: "../"}
	if got := static.ConvHref(&Note{ID: 1, Session: "s1"}); got != "" {
		t.Errorf("static conversation href = %q, want none", got)
	}
}