package main

import (
	"bytes"
	"compress/gzip"
	"encoding/json"
	"fmt"
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"
)

const testLogsToken = "logs-read-token-0123456789abcdef"

func newLogsAPI(t *testing.T) (*API, string) {
	t.Helper()
	api, _ := newTestAPI()
	dir := t.TempDir()
	api.Logs = NewLogs(dir, testLogsToken)
	return api, dir
}

func gzipped(t *testing.T, text string) []byte {
	t.Helper()
	var b bytes.Buffer
	zw := gzip.NewWriter(&b)
	if _, err := zw.Write([]byte(text)); err != nil {
		t.Fatal(err)
	}
	if err := zw.Close(); err != nil {
		t.Fatal(err)
	}
	return b.Bytes()
}

func putLog(t *testing.T, h http.Handler, name, token string, body []byte, encoding string) *httptest.ResponseRecorder {
	t.Helper()
	req := httptest.NewRequest("PUT", "/v1/logs/"+name, bytes.NewReader(body))
	req.Header.Set("Authorization", "Bearer "+token)
	req.Header.Set("Content-Type", "text/plain; charset=utf-8")
	if encoding != "" {
		req.Header.Set("Content-Encoding", encoding)
	}
	rec := httptest.NewRecorder()
	h.ServeHTTP(rec, req)
	return rec
}

func TestTheCarSendsALogAndTheOwnerReadsIt(t *testing.T) {
	api, _ := newLogsAPI(t)
	h := api.Routes()
	const name = "signal-recording-20261027-085240.txt"
	text := "Signal recording, 37 captures\nlistening to 108 assistance properties\n"

	if rec := putLog(t, h, name, testToken, gzipped(t, text), "gzip"); rec.Code != http.StatusNoContent {
		t.Fatalf("put: %d %s", rec.Code, rec.Body)
	}

	rec := do(t, h, "GET", "/v1/logs", testLogsToken, "")
	if rec.Code != 200 {
		t.Fatalf("list: %d %s", rec.Code, rec.Body)
	}
	var list struct {
		Logs []logEntry `json:"logs"`
	}
	if err := json.Unmarshal(rec.Body.Bytes(), &list); err != nil || len(list.Logs) != 1 || list.Logs[0].Name != name ||
		list.Logs[0].Bytes != int64(len(text)) {
		t.Fatalf("list: %v %s", err, rec.Body)
	}

	rec = do(t, h, "GET", "/v1/logs/"+name, testLogsToken, "")
	if rec.Code != 200 || rec.Body.String() != text || !strings.HasPrefix(rec.Header().Get("Content-Type"), "text/plain") {
		t.Fatalf("get: %d %q", rec.Code, rec.Body)
	}

	// Sent again (a retry), it replaces itself.
	if rec := putLog(t, h, name, testToken, []byte("again\n"), ""); rec.Code != http.StatusNoContent {
		t.Fatalf("put again: %d", rec.Code)
	}
	if rec := do(t, h, "GET", "/v1/logs/"+name, testLogsToken, ""); rec.Body.String() != "again\n" {
		t.Fatalf("replaced: %q", rec.Body)
	}
}

func TestLogTokensDoNotCross(t *testing.T) {
	api, _ := newLogsAPI(t)
	h := api.Routes()
	name := "signal-recording-1.txt"
	if rec := putLog(t, h, name, testLogsToken, []byte("x"), ""); rec.Code != http.StatusUnauthorized {
		t.Fatalf("the read token wrote: %d", rec.Code)
	}
	if rec := putLog(t, h, name, testToken, []byte("x"), ""); rec.Code != http.StatusNoContent {
		t.Fatalf("put: %d", rec.Code)
	}
	for _, path := range []string{"/v1/logs", "/v1/logs/" + name} {
		for _, token := range []string{"", testToken, testLogsToken + "x"} {
			if rec := do(t, h, "GET", path, token, ""); rec.Code != http.StatusUnauthorized {
				t.Fatalf("GET %s with %q: %d", path, token, rec.Code)
			}
		}
	}
}

func TestReadingIsOffWithoutALogsToken(t *testing.T) {
	api, _ := newLogsAPI(t)
	api.Logs.ReadToken = ""
	h := api.Routes()
	if rec := putLog(t, h, "a.txt", testToken, []byte("x"), ""); rec.Code != http.StatusNoContent {
		t.Fatalf("put: %d", rec.Code)
	}
	if rec := do(t, h, "GET", "/v1/logs", "", ""); rec.Code != http.StatusNotFound {
		t.Fatalf("list: %d", rec.Code)
	}
}

func TestBadLogsAreRefused(t *testing.T) {
	api, dir := newLogsAPI(t)
	h := api.Routes()
	for _, c := range []struct {
		name, encoding string
		body           []byte
		want           int
	}{
		{"..%2Fescape.txt", "", []byte("x"), http.StatusBadRequest},
		{"Upper.txt", "", []byte("x"), http.StatusBadRequest},
		{"no-suffix", "", []byte("x"), http.StatusBadRequest},
		{".hidden.txt", "", []byte("x"), http.StatusBadRequest},
		{"a.txt", "gzip", []byte("not gzip"), http.StatusBadRequest},
		{"a.txt", "br", []byte("x"), http.StatusUnsupportedMediaType},
		{"a.txt", "", []byte{0xff, 0xfe, 0x00}, http.StatusBadRequest},
		{"a.txt", "", make([]byte, maxLogWireBytes+1), http.StatusRequestEntityTooLarge},
		{"a.txt", "gzip", gzipped(t, strings.Repeat("a", maxLogBytes+1)), http.StatusRequestEntityTooLarge},
	} {
		if rec := putLog(t, h, c.name, testToken, c.body, c.encoding); rec.Code != c.want {
			t.Errorf("%s %s: %d, want %d (%s)", c.name, c.encoding, rec.Code, c.want, rec.Body)
		}
	}
	if files, _ := os.ReadDir(dir); len(files) != 0 {
		t.Fatalf("stored: %v", files)
	}
	if rec := do(t, h, "GET", "/v1/logs/missing.txt", testLogsToken, ""); rec.Code != http.StatusNotFound {
		t.Fatalf("missing: %d", rec.Code)
	}
}

func TestOldAndSurplusLogsArePruned(t *testing.T) {
	dir := t.TempDir()
	l := NewLogs(dir, testLogsToken)
	// The new file gets the real time as its own, so the others are placed before it.
	now := time.Now()
	old := filepath.Join(dir, "old.txt")
	if err := os.WriteFile(old, []byte("x"), 0o600); err != nil {
		t.Fatal(err)
	}
	if err := os.Chtimes(old, now.Add(-maxLogAge-time.Hour), now.Add(-maxLogAge-time.Hour)); err != nil {
		t.Fatal(err)
	}
	for i := 0; i < maxLogFiles+5; i++ {
		p := filepath.Join(dir, fmt.Sprintf("f-%03d.txt", i))
		if err := os.WriteFile(p, []byte("x"), 0o600); err != nil {
			t.Fatal(err)
		}
		at := now.Add(-time.Duration(maxLogFiles+5-i) * time.Minute)
		if err := os.Chtimes(p, at, at); err != nil {
			t.Fatal(err)
		}
	}
	if err := l.save("new.txt", []byte("y")); err != nil {
		t.Fatal(err)
	}
	entries, _ := l.entries()
	if len(entries) != maxLogFiles || entries[0].Name != "new.txt" {
		t.Fatalf("%d kept, first %s", len(entries), entries[0].Name)
	}
	if _, err := os.Stat(old); !os.IsNotExist(err) {
		t.Fatal("the old one is still there")
	}
	if _, err := os.Stat(filepath.Join(dir, "f-000.txt")); !os.IsNotExist(err) {
		t.Fatal("the oldest surplus one is still there")
	}
}

func TestLogsConfig(t *testing.T) {
	base := map[string]string{"INFLUX_URL": "http://i", "INFLUX_TOKEN": "t", "INFLUX_ORG": "o", "INGEST_TOKEN": testToken}
	env := func(extra map[string]string) func(string) string {
		return func(k string) string {
			if v, ok := extra[k]; ok {
				return v
			}
			return base[k]
		}
	}
	for _, c := range []struct {
		extra map[string]string
		ok    bool
	}{
		{map[string]string{}, true},
		{map[string]string{"LOGS_DIR": "/l"}, true},
		{map[string]string{"LOGS_DIR": "/l", "LOGS_TOKEN": testLogsToken}, true},
		{map[string]string{"LOGS_TOKEN": testLogsToken}, false},
		{map[string]string{"LOGS_DIR": "/l", "LOGS_TOKEN": "short"}, false},
		{map[string]string{"LOGS_DIR": "/l", "LOGS_TOKEN": testToken}, false},
	} {
		if _, err := loadConfig(env(c.extra)); (err == nil) != c.ok {
			t.Errorf("%v: %v", c.extra, err)
		}
	}
}