package config

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
)

func TestLoad_AllFields(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "config.yaml")

	yaml := `
port: 9090
api_keys:
  - key1
  - key2
claude_binary: /usr/bin/claude
sanitize:
  tools:
    - from: tool_a
      to: tool_b
  system:
    - match: foo
      replace: bar
  body:
    - match: baz
      replace: qux
logging:
  level: debug
  file: /tmp/test.log
  max_size_mb: 50
  max_backups: 3
  max_age_days: 7
  compress: true
telemetry:
  service_name: my-proxy
  export:
    endpoint: http://localhost:4317
    insecure: true
    headers:
      x-token: abc
  embedded:
    enabled: true
    port: 9999
    perses_binary: /usr/bin/perses
    vm_binary: /usr/bin/vm
    vm_port: 9428
    bin_dir: /opt/bin
`
	if err := os.WriteFile(path, []byte(yaml), 0644); err != nil {
		t.Fatal(err)
	}

	cfg, err := Load(path)
	if err != nil {
		t.Fatalf("Load returned error: %v", err)
	}

	if cfg.Port != 9090 {
		t.Errorf("Port = %d, want 9090", cfg.Port)
	}
	if len(cfg.APIKeys) != 2 || cfg.APIKeys[0] != "key1" || cfg.APIKeys[1] != "key2" {
		t.Errorf("APIKeys = %v, want [key1 key2]", cfg.APIKeys)
	}
	if cfg.ClaudeBinary != "/usr/bin/claude" {
		t.Errorf("ClaudeBinary = %q, want /usr/bin/claude", cfg.ClaudeBinary)
	}

	// Sanitize
	if len(cfg.Sanitize.Tools) != 1 || cfg.Sanitize.Tools[0].From != "tool_a" || cfg.Sanitize.Tools[0].To != "tool_b" {
		t.Errorf("Sanitize.Tools = %v", cfg.Sanitize.Tools)
	}
	if len(cfg.Sanitize.System) != 1 || cfg.Sanitize.System[0].Match != "foo" {
		t.Errorf("Sanitize.System = %v", cfg.Sanitize.System)
	}
	if len(cfg.Sanitize.Body) != 1 || cfg.Sanitize.Body[0].Match != "baz" {
		t.Errorf("Sanitize.Body = %v", cfg.Sanitize.Body)
	}

	// Logging
	if cfg.Logging.Level != "debug" {
		t.Errorf("Logging.Level = %q, want debug", cfg.Logging.Level)
	}
	if cfg.Logging.File != "/tmp/test.log" {
		t.Errorf("Logging.File = %q", cfg.Logging.File)
	}
	if cfg.Logging.MaxSizeMB != 50 {
		t.Errorf("Logging.MaxSizeMB = %d, want 50", cfg.Logging.MaxSizeMB)
	}
	if cfg.Logging.MaxBackups != 3 {
		t.Errorf("Logging.MaxBackups = %d, want 3", cfg.Logging.MaxBackups)
	}
	if cfg.Logging.MaxAgeDays != 7 {
		t.Errorf("Logging.MaxAgeDays = %d, want 7", cfg.Logging.MaxAgeDays)
	}
	if !cfg.Logging.Compress {
		t.Error("Logging.Compress = false, want true")
	}

	// Telemetry
	if cfg.Telemetry.ServiceName != "my-proxy" {
		t.Errorf("Telemetry.ServiceName = %q, want my-proxy", cfg.Telemetry.ServiceName)
	}
	if cfg.Telemetry.Export.Endpoint != "http://localhost:4317" {
		t.Errorf("Export.Endpoint = %q", cfg.Telemetry.Export.Endpoint)
	}
	if !cfg.Telemetry.Export.Insecure {
		t.Error("Export.Insecure = false, want true")
	}
	if !cfg.Telemetry.Export.Enabled() {
		t.Error("Export.Enabled() = false, want true")
	}
	if cfg.Telemetry.Export.Headers["x-token"] != "abc" {
		t.Errorf("Export.Headers = %v", cfg.Telemetry.Export.Headers)
	}

	// Embedded
	if !cfg.Telemetry.Embedded.Enabled {
		t.Error("Embedded.Enabled = false, want true")
	}
	if cfg.Telemetry.Embedded.Port != 9999 {
		t.Errorf("Embedded.Port = %d, want 9999", cfg.Telemetry.Embedded.Port)
	}
	if cfg.Telemetry.Embedded.PersesBinary != "/usr/bin/perses" {
		t.Errorf("Embedded.PersesBinary = %q", cfg.Telemetry.Embedded.PersesBinary)
	}
	if cfg.Telemetry.Embedded.VMBinary != "/usr/bin/vm" {
		t.Errorf("Embedded.VMBinary = %q", cfg.Telemetry.Embedded.VMBinary)
	}
	if cfg.Telemetry.Embedded.VMPort != 9428 {
		t.Errorf("Embedded.VMPort = %d, want 9428", cfg.Telemetry.Embedded.VMPort)
	}
	if cfg.Telemetry.Embedded.BinDir != "/opt/bin" {
		t.Errorf("Embedded.BinDir = %q", cfg.Telemetry.Embedded.BinDir)
	}
}

func TestLoad_Defaults(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "config.yaml")

	// Minimal YAML — only api_keys
	if err := os.WriteFile(path, []byte("api_keys:\n  - k1\n"), 0644); err != nil {
		t.Fatal(err)
	}

	cfg, err := Load(path)
	if err != nil {
		t.Fatalf("Load returned error: %v", err)
	}

	tests := []struct {
		name string
		got  interface{}
		want interface{}
	}{
		{"Port", cfg.Port, 8080},
		{"Logging.Level", cfg.Logging.Level, "info"},
		{"Logging.MaxSizeMB", cfg.Logging.MaxSizeMB, 100},
		{"Logging.MaxBackups", cfg.Logging.MaxBackups, 5},
		{"Logging.MaxAgeDays", cfg.Logging.MaxAgeDays, 30},
		{"Telemetry.ServiceName", cfg.Telemetry.ServiceName, "anthropic-proxy"},
		{"Embedded.Port", cfg.Telemetry.Embedded.Port, 8080},
		{"Embedded.VMBinary", cfg.Telemetry.Embedded.VMBinary, "victoria-metrics"},
		{"Embedded.PersesBinary", cfg.Telemetry.Embedded.PersesBinary, "perses"},
		{"Embedded.VMPort", cfg.Telemetry.Embedded.VMPort, 8428},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			if tt.got != tt.want {
				t.Errorf("got %v, want %v", tt.got, tt.want)
			}
		})
	}
}

func TestLoad_MissingFile(t *testing.T) {
	_, err := Load("/nonexistent/path/config.yaml")
	if err == nil {
		t.Fatal("expected error for missing file, got nil")
	}
	if !strings.Contains(err.Error(), "read config") {
		t.Errorf("error = %q, want it to contain 'read config'", err.Error())
	}
}

func TestLoad_DeprecatedClaudeCredentials(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "config.yaml")

	yaml := `
api_keys:
  - k1
claude_credentials: "/some/path"
`
	if err := os.WriteFile(path, []byte(yaml), 0644); err != nil {
		t.Fatal(err)
	}

	_, err := Load(path)
	if err == nil {
		t.Fatal("expected error for deprecated claude_credentials, got nil")
	}
	if !strings.Contains(err.Error(), "no longer supported") {
		t.Errorf("error = %q, want it to contain 'no longer supported'", err.Error())
	}
}

func TestLoad_EmptyClaudeCredentials(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "config.yaml")

	// Empty string value should NOT trigger the deprecation error
	yaml := `
api_keys:
  - k1
claude_credentials: ""
`
	if err := os.WriteFile(path, []byte(yaml), 0644); err != nil {
		t.Fatal(err)
	}

	cfg, err := Load(path)
	if err != nil {
		t.Fatalf("empty claude_credentials should not error: %v", err)
	}
	if cfg.Port != 8080 {
		t.Errorf("Port = %d, want 8080", cfg.Port)
	}
}

func TestLoad_InvalidYAML(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "config.yaml")

	// Truly invalid YAML that causes a parse error
	if err := os.WriteFile(path, []byte("port:\n  - bad\n  indent: broken\n"), 0644); err != nil {
		t.Fatal(err)
	}

	_, err := Load(path)
	if err == nil {
		t.Fatal("expected error for invalid YAML, got nil")
	}
	if !strings.Contains(err.Error(), "parse config") {
		t.Errorf("error = %q, want it to contain 'parse config'", err.Error())
	}
}

func TestExportConfig_Enabled(t *testing.T) {
	tests := []struct {
		name     string
		endpoint string
		want     bool
	}{
		{"empty endpoint", "", false},
		{"set endpoint", "http://localhost:4317", true},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			e := ExportConfig{Endpoint: tt.endpoint}
			if got := e.Enabled(); got != tt.want {
				t.Errorf("Enabled() = %v, want %v", got, tt.want)
			}
		})
	}
}