package api

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

func TestSemverAtLeast(t *testing.T) {
	tests := []struct {
		version  string
		minimum  string
		expected bool
	}{
		{"2.1.0", "2.0.0", true},
		{"2.0.0", "2.0.0", true},
		{"2.0.5", "2.0.0", true},
		{"2.1.5", "2.1.0", true},
		{"2.0.9", "2.1.0", false},
		{"1.9.9", "2.0.0", false},
		{"3.0.0", "2.9.9", true},
		{"2.0.0", "2.0.1", false},
	}

	for _, tt := range tests {
		t.Run(tt.version+">="+tt.minimum, func(t *testing.T) {
			got := semverAtLeast(tt.version, tt.minimum)
			if got != tt.expected {
				t.Errorf("semverAtLeast(%q, %q) = %v, want %v", tt.version, tt.minimum, got, tt.expected)
			}
		})
	}
}

func TestCheckEngineVersion_Compatible(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		json.NewEncoder(w).Encode(map[string]string{"version": "2.1.0"})
	}))
	defer srv.Close()

	clientVersion = "2.2.0"
	minEngineVersion = "2.1.0"
	defer func() { clientVersion = ""; minEngineVersion = "" }()

	c := &Client{
		baseURL:    srv.URL,
		httpClient: &http.Client{},
	}

	// Should not panic or exit
	c.checkEngineVersion()

	if !c.versionChecked {
		t.Error("versionChecked should be true after check")
	}
}

func TestCheckEngineVersion_SkipsWhenDev(t *testing.T) {
	clientVersion = "dev"
	minEngineVersion = "dev"
	defer func() { clientVersion = ""; minEngineVersion = "" }()

	c := &Client{
		baseURL:    "http://localhost:99999",
		httpClient: &http.Client{},
	}

	// Should not attempt connection
	c.checkEngineVersion()

	if !c.versionChecked {
		t.Error("versionChecked should be true after skipping")
	}
}

func TestCheckEngineVersion_SkipsWhenEmpty(t *testing.T) {
	clientVersion = "1.0.0"
	minEngineVersion = ""
	defer func() { clientVersion = ""; minEngineVersion = "" }()

	c := &Client{
		baseURL:    "http://localhost:99999",
		httpClient: &http.Client{},
	}

	c.checkEngineVersion()

	if !c.versionChecked {
		t.Error("versionChecked should be true after skipping")
	}
}

func TestCheckEngineVersion_SkipsWhenUnreachable(t *testing.T) {
	clientVersion = "2.0.0"
	minEngineVersion = "2.0.0"
	defer func() { clientVersion = ""; minEngineVersion = "" }()

	c := &Client{
		baseURL:    "http://localhost:99999",
		httpClient: &http.Client{},
	}

	// Should not panic — just skip
	c.checkEngineVersion()

	if !c.versionChecked {
		t.Error("versionChecked should be true even when unreachable")
	}
}

func TestCheckEngineVersion_CachedAfterFirstCall(t *testing.T) {
	callCount := 0
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		callCount++
		json.NewEncoder(w).Encode(map[string]string{"version": "2.1.0"})
	}))
	defer srv.Close()

	clientVersion = "2.1.0"
	minEngineVersion = "2.0.0"
	defer func() { clientVersion = ""; minEngineVersion = "" }()

	c := &Client{
		baseURL:    srv.URL,
		httpClient: &http.Client{},
	}

	c.checkEngineVersion()
	c.checkEngineVersion()
	c.checkEngineVersion()

	if callCount != 1 {
		t.Errorf("expected 1 status call, got %d", callCount)
	}
}