package synor

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

// TestClientCreation tests client initialization.
func TestClientCreation(t *testing.T) {
	t.Run("creates client with API key", func(t *testing.T) {
		client := NewClient("test-api-key")
		if client == nil {
			t.Fatal("expected non-nil client")
		}
	})

	t.Run("creates client with config", func(t *testing.T) {
		config := Config{
			APIKey:    "test-api-key",
			Endpoint:  "https://custom.api.com",
			Strategy:  Cost,
			Precision: FP16,
			Timeout:   60 * time.Second,
		}
		client := NewClientWithConfig(config)
		if client == nil {
			t.Fatal("expected non-nil client")
		}
		if client.config.Endpoint != "https://custom.api.com" {
			t.Errorf("expected custom endpoint, got %s", client.config.Endpoint)
		}
	})
}

// TestDefaultConfig tests default configuration.
func TestDefaultConfig(t *testing.T) {
	config := DefaultConfig("my-key")

	if config.APIKey != "my-key" {
		t.Errorf("expected API key 'my-key', got %s", config.APIKey)
	}
	if config.Endpoint != DefaultEndpoint {
		t.Errorf("expected default endpoint, got %s", config.Endpoint)
	}
	if config.Strategy != Balanced {
		t.Errorf("expected Balanced strategy, got %s", config.Strategy)
	}
	if config.Precision != FP32 {
		t.Errorf("expected FP32 precision, got %s", config.Precision)
	}
	if config.Timeout != 30*time.Second {
		t.Errorf("expected 30s timeout, got %v", config.Timeout)
	}
}

// TestTensorCreation tests tensor creation.
func TestTensorCreation(t *testing.T) {
	t.Run("creates tensor from data", func(t *testing.T) {
		data := []float32{1.0, 2.0, 3.0, 4.0, 5.0, 6.0}
		shape := []int{2, 3}
		tensor := NewTensor(data, shape, FP32)

		if tensor == nil {
			t.Fatal("expected non-nil tensor")
		}
		if len(tensor.Data) != 6 {
			t.Errorf("expected 6 elements, got %d", len(tensor.Data))
		}
		if len(tensor.Shape) != 2 {
			t.Errorf("expected 2 dimensions, got %d", len(tensor.Shape))
		}
		if tensor.DType != FP32 {
			t.Errorf("expected FP32 dtype, got %s", tensor.DType)
		}
	})

	t.Run("creates zeros tensor", func(t *testing.T) {
		tensor := Zeros([]int{3, 4}, FP32)

		if tensor == nil {
			t.Fatal("expected non-nil tensor")
		}
		if len(tensor.Data) != 12 {
			t.Errorf("expected 12 elements, got %d", len(tensor.Data))
		}
		for i, v := range tensor.Data {
			if v != 0.0 {
				t.Errorf("expected 0 at index %d, got %f", i, v)
			}
		}
	})
}

// TestTensorSerialize tests tensor serialization.
func TestTensorSerialize(t *testing.T) {
	data := []float32{1.0, 2.0, 3.0, 4.0}
	shape := []int{2, 2}
	tensor := NewTensor(data, shape, FP32)

	serialized := tensor.Serialize()

	if _, ok := serialized["data"]; !ok {
		t.Error("expected 'data' field in serialized tensor")
	}
	if _, ok := serialized["shape"]; !ok {
		t.Error("expected 'shape' field in serialized tensor")
	}
	if _, ok := serialized["dtype"]; !ok {
		t.Error("expected 'dtype' field in serialized tensor")
	}
	if serialized["dtype"] != FP32 {
		t.Errorf("expected FP32 dtype, got %v", serialized["dtype"])
	}
}

// TestProcessorTypes tests processor type constants.
func TestProcessorTypes(t *testing.T) {
	types := []ProcessorType{CPU, GPU, TPU, NPU, LPU, FPGA, WASM, WebGPU}
	expected := []string{"cpu", "gpu", "tpu", "npu", "lpu", "fpga", "wasm", "webgpu"}

	for i, pt := range types {
		if string(pt) != expected[i] {
			t.Errorf("expected %s, got %s", expected[i], pt)
		}
	}
}

// TestPrecisionTypes tests precision type constants.
func TestPrecisionTypes(t *testing.T) {
	precisions := []Precision{FP64, FP32, FP16, BF16, INT8, INT4}
	expected := []string{"fp64", "fp32", "fp16", "bf16", "int8", "int4"}

	for i, p := range precisions {
		if string(p) != expected[i] {
			t.Errorf("expected %s, got %s", expected[i], p)
		}
	}
}

// TestJobStatus tests job status constants.
func TestJobStatus(t *testing.T) {
	statuses := []JobStatus{Pending, Queued, Running, Completed, Failed, Cancelled}
	expected := []string{"pending", "queued", "running", "completed", "failed", "cancelled"}

	for i, s := range statuses {
		if string(s) != expected[i] {
			t.Errorf("expected %s, got %s", expected[i], s)
		}
	}
}

// TestBalancingStrategies tests balancing strategy constants.
func TestBalancingStrategies(t *testing.T) {
	strategies := []BalancingStrategy{Speed, Cost, Energy, Latency, Balanced}
	expected := []string{"speed", "cost", "energy", "latency", "balanced"}

	for i, s := range strategies {
		if string(s) != expected[i] {
			t.Errorf("expected %s, got %s", expected[i], s)
		}
	}
}

// TestSubmitJob tests job submission with mock server.
func TestSubmitJob(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path == "/jobs" && r.Method == "POST" {
			w.WriteHeader(http.StatusOK)
			json.NewEncoder(w).Encode(map[string]interface{}{
				"job_id": "job-123",
			})
			return
		}
		w.WriteHeader(http.StatusNotFound)
	}))
	defer server.Close()

	config := Config{
		APIKey:   "test-key",
		Endpoint: server.URL,
		Timeout:  5 * time.Second,
	}
	client := NewClientWithConfig(config)

	ctx := context.Background()
	job, err := client.SubmitJob(ctx, "matmul", map[string]interface{}{
		"a": map[string]interface{}{"data": "base64", "shape": []int{2, 2}},
		"b": map[string]interface{}{"data": "base64", "shape": []int{2, 2}},
	})

	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if job.ID != "job-123" {
		t.Errorf("expected job ID 'job-123', got %s", job.ID)
	}
}

// TestGetJobStatus tests getting job status with mock server.
func TestGetJobStatus(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path == "/jobs/job-123" && r.Method == "GET" {
			w.WriteHeader(http.StatusOK)
			json.NewEncoder(w).Encode(map[string]interface{}{
				"job_id": "job-123",
				"status": "completed",
				"data":   map[string]interface{}{"result": "success"},
			})
			return
		}
		w.WriteHeader(http.StatusNotFound)
	}))
	defer server.Close()

	config := Config{
		APIKey:   "test-key",
		Endpoint: server.URL,
		Timeout:  5 * time.Second,
	}
	client := NewClientWithConfig(config)

	ctx := context.Background()
	result, err := client.GetJobStatus(ctx, "job-123")

	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if result.Status != Completed {
		t.Errorf("expected Completed status, got %s", result.Status)
	}
}

// TestGetPricing tests getting pricing information with mock server.
func TestGetPricing(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path == "/pricing" && r.Method == "GET" {
			w.WriteHeader(http.StatusOK)
			json.NewEncoder(w).Encode(map[string]interface{}{
				"pricing": []map[string]interface{}{
					{
						"processor_type":  "gpu",
						"spot_price":      0.0001,
						"avg_price_24h":   0.00012,
						"aws_equivalent":  0.001,
						"savings_percent": 90.0,
					},
					{
						"processor_type":  "tpu",
						"spot_price":      0.0002,
						"avg_price_24h":   0.00022,
						"aws_equivalent":  0.002,
						"savings_percent": 89.0,
					},
				},
			})
			return
		}
		w.WriteHeader(http.StatusNotFound)
	}))
	defer server.Close()

	config := Config{
		APIKey:   "test-key",
		Endpoint: server.URL,
		Timeout:  5 * time.Second,
	}
	client := NewClientWithConfig(config)

	ctx := context.Background()
	pricing, err := client.GetPricing(ctx)

	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if len(pricing) != 2 {
		t.Errorf("expected 2 pricing entries, got %d", len(pricing))
	}
}

// TestSynorError tests error formatting.
func TestSynorError(t *testing.T) {
	err := &SynorError{
		Message:    "Invalid API key",
		StatusCode: 401,
	}

	expected := "synor: Invalid API key (status 401)"
	if err.Error() != expected {
		t.Errorf("expected error message '%s', got '%s'", expected, err.Error())
	}
}

// TestAPIError tests handling of API errors.
func TestAPIError(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusUnauthorized)
		json.NewEncoder(w).Encode(map[string]interface{}{
			"message": "Invalid API key",
		})
	}))
	defer server.Close()

	config := Config{
		APIKey:   "bad-key",
		Endpoint: server.URL,
		Timeout:  5 * time.Second,
	}
	client := NewClientWithConfig(config)

	ctx := context.Background()
	_, err := client.SubmitJob(ctx, "test", nil)

	if err == nil {
		t.Fatal("expected error, got nil")
	}

	synorErr, ok := err.(*SynorError)
	if !ok {
		t.Fatalf("expected SynorError, got %T", err)
	}
	if synorErr.StatusCode != 401 {
		t.Errorf("expected status 401, got %d", synorErr.StatusCode)
	}
}

// TestCancelJob tests job cancellation with mock server.
func TestCancelJob(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path == "/jobs/job-123" && r.Method == "DELETE" {
			w.WriteHeader(http.StatusOK)
			return
		}
		w.WriteHeader(http.StatusNotFound)
	}))
	defer server.Close()

	config := Config{
		APIKey:   "test-key",
		Endpoint: server.URL,
		Timeout:  5 * time.Second,
	}
	client := NewClientWithConfig(config)

	ctx := context.Background()
	err := client.CancelJob(ctx, "job-123")

	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
}

// TestJobMetrics tests job metrics structure.
func TestJobMetrics(t *testing.T) {
	metrics := JobMetrics{
		ExecutionTimeMs: 150.5,
		QueueTimeMs:     10.2,
		ProcessorType:   GPU,
		ProcessorID:     "gpu-001",
		FLOPS:           1e12,
		MemoryBytes:     1073741824,
		CostMicro:       100,
		EnergyMJ:        5.5,
	}

	if metrics.ExecutionTimeMs != 150.5 {
		t.Errorf("expected execution time 150.5, got %f", metrics.ExecutionTimeMs)
	}
	if metrics.ProcessorType != GPU {
		t.Errorf("expected GPU processor, got %s", metrics.ProcessorType)
	}
}

// TestPricingInfo tests pricing info structure.
func TestPricingInfo(t *testing.T) {
	pricing := PricingInfo{
		ProcessorType:  GPU,
		SpotPrice:      0.0001,
		AvgPrice24h:    0.00012,
		AWSEquivalent:  0.001,
		SavingsPercent: 90.0,
	}

	if pricing.ProcessorType != GPU {
		t.Errorf("expected GPU processor, got %s", pricing.ProcessorType)
	}
	if pricing.SavingsPercent != 90.0 {
		t.Errorf("expected 90%% savings, got %f%%", pricing.SavingsPercent)
	}
}

// TestJobResult tests job result structure.
func TestJobResult(t *testing.T) {
	result := JobResult{
		JobID:  "job-123",
		Status: Completed,
		Data:   map[string]interface{}{"output": "success"},
		Metrics: &JobMetrics{
			ExecutionTimeMs: 100,
			ProcessorType:   GPU,
		},
	}

	if result.JobID != "job-123" {
		t.Errorf("expected job ID 'job-123', got %s", result.JobID)
	}
	if result.Status != Completed {
		t.Errorf("expected Completed status, got %s", result.Status)
	}
	if result.Metrics == nil {
		t.Error("expected non-nil metrics")
	}
}