package app

import (
	"context"
	"encoding/json"
	"errors"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"
	"time"
)

type timeoutNetError struct{}

func (timeoutNetError) Error() string   { return "timeout" }
func (timeoutNetError) Timeout() bool   { return true }
func (timeoutNetError) Temporary() bool { return true }

func TestNormalizeCardRecognitionCandidates(t *testing.T) {
	got := normalizeCardRecognitionCandidates([]string{
		"ICCID: 8986-0401-7854-7796-048",
		"8986040178547796048",
		"89860401785477960480",
		"7986040178547796048",
		"898604017854779604",
		"898604017854779604800",
	})
	want := []string{
		"8986040178547796048",
		"89860401785477960480",
	}
	if len(got) != len(want) {
		t.Fatalf("len(got) = %d, want %d, got=%v", len(got), len(want), got)
	}
	for index := range want {
		if got[index] != want[index] {
			t.Fatalf("got[%d] = %s, want %s", index, got[index], want[index])
		}
	}
}

func TestRequestCardRecognitionModelUsesEinoMultimodalMessage(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
		if request.URL.Path != "/v1/chat/completions" {
			t.Errorf("path = %s, want /v1/chat/completions", request.URL.Path)
		}
		var body struct {
			Messages []struct {
				Content []struct {
					Type     string `json:"type"`
					ImageURL struct {
						URL string `json:"url"`
					} `json:"image_url"`
				} `json:"content"`
			} `json:"messages"`
		}
		if err := json.NewDecoder(request.Body).Decode(&body); err != nil {
			t.Errorf("decode request: %v", err)
		}
		if len(body.Messages) != 1 || len(body.Messages[0].Content) != 2 {
			t.Errorf("unexpected messages: %+v", body.Messages)
		} else if !strings.HasPrefix(body.Messages[0].Content[1].ImageURL.URL, "data:image/png;base64,") {
			t.Errorf("image url = %s", body.Messages[0].Content[1].ImageURL.URL)
		}
		writer.Header().Set("Content-Type", "application/json")
		_, _ = writer.Write([]byte(`{"id":"chatcmpl-test","object":"chat.completion","created":1,"model":"test-model","choices":[{"index":0,"message":{"role":"assistant","content":"{\"code\":\"CARD_RECOGNIZED\",\"iccid\":\"8986040178547796048\"}"},"finish_reason":"stop"}]}`))
	}))
	defer server.Close()

	content, err := requestCardRecognitionModel(context.Background(), cardRecognitionConfig{
		APIKey:    "test-key",
		BaseURL:   server.URL + "/v1",
		Model:     "test-model",
		Timeout:   3 * time.Second,
		MaxTokens: 64,
	}, []byte("image"), "image/png")
	if err != nil {
		t.Fatalf("requestCardRecognitionModel() error = %v", err)
	}
	if !strings.Contains(content, "8986040178547796048") {
		t.Fatalf("content = %s", content)
	}
}

func TestParseCardRecognitionResultMarkdownJSON(t *testing.T) {
	got := parseCardRecognitionResult("```json\n{\"code\":\"CARD_RECOGNIZED\",\"cardType\":\"iccid\",\"iccid\":\"8986040178547796048\",\"candidates\":[\"8986040178547796048\"],\"confidence\":1.2}\n```")
	if got.Code != cardRecognitionCodeRecognized {
		t.Fatalf("Code = %s, want %s", got.Code, cardRecognitionCodeRecognized)
	}
	if got.Confidence != 1 {
		t.Fatalf("Confidence = %v, want 1", got.Confidence)
	}
	if len(got.Candidates) != 1 || got.Candidates[0] != "8986040178547796048" {
		t.Fatalf("Candidates = %v", got.Candidates)
	}
}

func TestParseCardRecognitionResultAmbiguous(t *testing.T) {
	got := parseCardRecognitionResult(`{
		"code": "CARD_AMBIGUOUS",
		"cardType": "iccid",
		"candidates": ["8986040178547796048", "89860401785477960480"],
		"confidence": 0.84
	}`)
	if got.Code != cardRecognitionCodeAmbiguous {
		t.Fatalf("Code = %s, want %s", got.Code, cardRecognitionCodeAmbiguous)
	}
	if len(got.Candidates) != 2 {
		t.Fatalf("Candidates = %v", got.Candidates)
	}
}

func TestParseCardRecognitionResultFiltersInvalidCandidates(t *testing.T) {
	got := parseCardRecognitionResult(`{
		"code": "CARD_RECOGNIZED",
		"iccid": "13800008000",
		"candidates": ["898604017854779604", "898604017854779604800", "7986040178547796048"],
		"confidence": -0.4
	}`)
	if got.Confidence != 0 {
		t.Fatalf("Confidence = %v, want 0", got.Confidence)
	}
	if len(got.Candidates) != 0 {
		t.Fatalf("Candidates = %v, want empty", got.Candidates)
	}
}

func TestParseCardRecognitionResultFallbackFromText(t *testing.T) {
	got := parseCardRecognitionResult("识别到 ICCID 8986040178547796048，另一个候选是 89860401785477960480。")
	if got.Code != cardRecognitionCodeAmbiguous {
		t.Fatalf("Code = %s, want %s", got.Code, cardRecognitionCodeAmbiguous)
	}
	if len(got.Candidates) != 2 {
		t.Fatalf("Candidates = %v", got.Candidates)
	}
}

func TestClampCardRecognitionConfidence(t *testing.T) {
	if got := clampCardRecognitionConfidence(-0.1); got != 0 {
		t.Fatalf("negative clamp = %v, want 0", got)
	}
	if got := clampCardRecognitionConfidence(1.1); got != 1 {
		t.Fatalf("over one clamp = %v, want 1", got)
	}
	if got := clampCardRecognitionConfidence(0.5); got != 0.5 {
		t.Fatalf("normal clamp = %v, want 0.5", got)
	}
}

func TestIsCardRecognitionTimeoutError(t *testing.T) {
	ctx, cancel := context.WithTimeout(context.Background(), time.Nanosecond)
	defer cancel()
	<-ctx.Done()
	if !isCardRecognitionTimeoutError(ctx, errors.New("other")) {
		t.Fatal("deadline exceeded context should be treated as timeout")
	}
	if !isCardRecognitionTimeoutError(context.Background(), timeoutNetError{}) {
		t.Fatal("net timeout error should be treated as timeout")
	}
	if isCardRecognitionTimeoutError(context.Background(), errors.New("temporary unavailable")) {
		t.Fatal("non-timeout error should not be treated as timeout")
	}
}