package llm

import (
	"bytes"
	"context"
	"encoding/json"
	"io"
	"net/http"
	"testing"

	"github.com/mmmy/snapgo/internal/domain"
)

type roundTripFunc func(*http.Request) (*http.Response, error)

func (f roundTripFunc) RoundTrip(req *http.Request) (*http.Response, error) {
	return f(req)
}

func TestVisionClientSummarizeImageUsesChatCompletionImageURL(t *testing.T) {
	var requestBody map[string]any
	transport := roundTripFunc(func(r *http.Request) (*http.Response, error) {
		if r.URL.Path != "/v1/chat/completions" {
			t.Fatalf("expected /v1/chat/completions, got %s", r.URL.Path)
		}
		if got := r.Header.Get("Authorization"); got != "Bearer test-key" {
			t.Fatalf("unexpected auth header %q", got)
		}
		if err := json.NewDecoder(r.Body).Decode(&requestBody); err != nil {
			t.Fatalf("decode request: %v", err)
		}
		return &http.Response{
			StatusCode: http.StatusOK,
			Header:     http.Header{"Content-Type": []string{"application/json"}},
			Body:       io.NopCloser(bytes.NewBufferString(`{"choices":[{"message":{"content":"summary ok"}}]}`)),
		}, nil
	})

	client, err := NewVisionClient(domain.LLMProviderQwen, domain.LLMProviderConfig{
		BaseURL:     "https://example.test/v1",
		APIKey:      "test-key",
		Model:       "qwen-vl-plus",
		MaxTokens:   321,
		Temperature: 0.2,
		TimeoutSecs: 5,
	})
	if err != nil {
		t.Fatalf("new client: %v", err)
	}
	client.httpClient.Transport = transport

	text, err := client.SummarizeImage(context.Background(), "describe", "https://cdn.example.com/a.png")
	if err != nil {
		t.Fatalf("summarize image: %v", err)
	}
	if text != "summary ok" {
		t.Fatalf("expected response text, got %q", text)
	}
	if requestBody["model"] != "qwen-vl-plus" {
		t.Fatalf("expected model forwarded, got %#v", requestBody["model"])
	}
	if requestBody["max_tokens"] != float64(321) {
		t.Fatalf("expected max_tokens forwarded, got %#v", requestBody["max_tokens"])
	}

	messages := requestBody["messages"].([]any)
	content := messages[0].(map[string]any)["content"].([]any)
	if content[0].(map[string]any)["text"] != "describe" {
		t.Fatalf("expected prompt content, got %#v", content[0])
	}
	image := content[1].(map[string]any)
	if image["type"] != "image_url" {
		t.Fatalf("expected image_url item, got %#v", image)
	}
	url := image["image_url"].(map[string]any)["url"]
	if url != "https://cdn.example.com/a.png" {
		t.Fatalf("expected image url forwarded, got %#v", url)
	}
}

func TestChatCompletionsURLAcceptsFullEndpoint(t *testing.T) {
	full := "https://example.com/v1/chat/completions"
	if got := chatCompletionsURL(full); got != full {
		t.Fatalf("expected full endpoint unchanged, got %q", got)
	}
}