package config

import (
	"log/slog"
	"testing"
	"time"
)

func setRequired(t *testing.T) {
	t.Helper()
	t.Setenv("WIKIJS_URL", "https://wiki.example.com")
	t.Setenv("WIKIJS_API_KEY", "secret")
}

func TestLoadDefaults(t *testing.T) {
	setRequired(t)
	t.Setenv("WIKIJS_ENABLE_EDIT", "")
	t.Setenv("WIKIJS_TIMEOUT", "")
	t.Setenv("MCP_TRANSPORT", "")
	t.Setenv("MCP_ADDR", "")
	t.Setenv("MCP_PATH", "")
	t.Setenv("MCP_STATELESS", "")
	t.Setenv("MCP_AUTH_TOKEN", "")
	t.Setenv("LOG_LEVEL", "")

	cfg, err := Load()
	if err != nil {
		t.Fatalf("Load() error = %v", err)
	}
	if cfg.Transport != TransportStdio {
		t.Errorf("Transport = %q, want %q", cfg.Transport, TransportStdio)
	}
	if cfg.Addr != DefaultAddr {
		t.Errorf("Addr = %q, want %q", cfg.Addr, DefaultAddr)
	}
	if cfg.Path != DefaultPath {
		t.Errorf("Path = %q, want %q", cfg.Path, DefaultPath)
	}
	if cfg.Timeout != DefaultTimeout {
		t.Errorf("Timeout = %v, want %v", cfg.Timeout, DefaultTimeout)
	}
	if cfg.EnableEdit {
		t.Error("EnableEdit = true, want false")
	}
	if cfg.Stateless {
		t.Error("Stateless = true, want false")
	}
	if cfg.LogLevel != slog.LevelInfo {
		t.Errorf("LogLevel = %v, want info", cfg.LogLevel)
	}
	if err := cfg.Validate(); err != nil {
		t.Errorf("Validate() error = %v", err)
	}
}

func TestLoadCustomValues(t *testing.T) {
	setRequired(t)
	t.Setenv("WIKIJS_ENABLE_EDIT", "true")
	t.Setenv("WIKIJS_TIMEOUT", "5s")
	t.Setenv("MCP_TRANSPORT", "HTTP")
	t.Setenv("MCP_ADDR", "127.0.0.1:9000")
	t.Setenv("MCP_PATH", "/mcp/")
	t.Setenv("MCP_STATELESS", "1")
	t.Setenv("MCP_AUTH_TOKEN", "token")
	t.Setenv("LOG_LEVEL", "debug")

	cfg, err := Load()
	if err != nil {
		t.Fatalf("Load() error = %v", err)
	}
	if cfg.Transport != TransportHTTP {
		t.Errorf("Transport = %q, want %q", cfg.Transport, TransportHTTP)
	}
	if cfg.Addr != "127.0.0.1:9000" {
		t.Errorf("Addr = %q", cfg.Addr)
	}
	if cfg.Path != "/mcp/" {
		t.Errorf("Path = %q", cfg.Path)
	}
	if cfg.Timeout != 5*time.Second {
		t.Errorf("Timeout = %v", cfg.Timeout)
	}
	if !cfg.EnableEdit || !cfg.Stateless {
		t.Errorf("EnableEdit = %v, Stateless = %v, want both true", cfg.EnableEdit, cfg.Stateless)
	}
	if cfg.AuthToken != "token" {
		t.Errorf("AuthToken = %q", cfg.AuthToken)
	}
	if cfg.LogLevel != slog.LevelDebug {
		t.Errorf("LogLevel = %v, want debug", cfg.LogLevel)
	}
}

func TestLoadRequired(t *testing.T) {
	tests := []struct {
		name    string
		url     string
		apiKey  string
		wantErr bool
	}{
		{name: "missing url", apiKey: "secret", wantErr: true},
		{name: "missing key", url: "https://wiki.example.com", wantErr: true},
		{name: "present", url: "https://wiki.example.com", apiKey: "secret"},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			t.Setenv("WIKIJS_URL", tt.url)
			t.Setenv("WIKIJS_API_KEY", tt.apiKey)
			cfg, err := Load()
			if err != nil {
				t.Fatalf("Load() error = %v", err)
			}
			if gotErr := cfg.Validate() != nil; gotErr != tt.wantErr {
				t.Fatalf("Validate() error = %v, wantErr %v", cfg.Validate(), tt.wantErr)
			}
		})
	}
}

func TestLoadInvalidValues(t *testing.T) {
	tests := []struct {
		name  string
		key   string
		value string
	}{
		{name: "edit bool", key: "WIKIJS_ENABLE_EDIT", value: "maybe"},
		{name: "stateless bool", key: "MCP_STATELESS", value: "maybe"},
		{name: "timeout", key: "WIKIJS_TIMEOUT", value: "soon"},
		{name: "log level", key: "LOG_LEVEL", value: "verbose"},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			setRequired(t)
			t.Setenv(tt.key, tt.value)
			if _, err := Load(); err == nil {
				t.Fatal("Load() error = nil, want error")
			}
		})
	}
}

func TestValidateHTTPAuth(t *testing.T) {
	tests := []struct {
		name    string
		addr    string
		token   string
		wantErr bool
	}{
		{name: "all interfaces without token", addr: ":8080", wantErr: true},
		{name: "all interfaces with token", addr: ":8080", token: "secret"},
		{name: "ipv4 any without token", addr: "0.0.0.0:8080", wantErr: true},
		{name: "ipv4 loopback", addr: "127.0.0.1:8080"},
		{name: "ipv6 loopback", addr: "[::1]:8080"},
		{name: "localhost", addr: "localhost:8080"},
		{name: "remote hostname without token", addr: "wiki.internal:8080", wantErr: true},
		{name: "missing port", addr: "127.0.0.1", wantErr: true},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			cfg := Config{
				WikiJSURL:    "https://wiki.example.com",
				WikiJSAPIKey: "secret",
				Transport:    TransportHTTP,
				Addr:         tt.addr,
				Path:         DefaultPath,
				Timeout:      DefaultTimeout,
				AuthToken:    tt.token,
			}
			if gotErr := cfg.Validate() != nil; gotErr != tt.wantErr {
				t.Fatalf("Validate() error = %v, wantErr %v", cfg.Validate(), tt.wantErr)
			}
		})
	}
}

func TestValidate(t *testing.T) {
	valid := func() Config {
		return Config{
			WikiJSURL:    "https://wiki.example.com",
			WikiJSAPIKey: "secret",
			Transport:    TransportStdio,
			Addr:         DefaultAddr,
			Path:         DefaultPath,
			Timeout:      DefaultTimeout,
		}
	}

	tests := []struct {
		name    string
		mutate  func(*Config)
		wantErr bool
	}{
		{name: "valid"},
		{name: "missing url", mutate: func(c *Config) { c.WikiJSURL = "" }, wantErr: true},
		{name: "missing key", mutate: func(c *Config) { c.WikiJSAPIKey = "" }, wantErr: true},
		{name: "relative url", mutate: func(c *Config) { c.WikiJSURL = "wiki.example.com" }, wantErr: true},
		{name: "url with query", mutate: func(c *Config) { c.WikiJSURL = "https://wiki.example.com/?a=1" }, wantErr: true},
		{name: "ftp url", mutate: func(c *Config) { c.WikiJSURL = "ftp://wiki.example.com" }, wantErr: true},
		{name: "bad transport", mutate: func(c *Config) { c.Transport = "sse" }, wantErr: true},
		{name: "empty addr", mutate: func(c *Config) { c.Addr = "" }, wantErr: true},
		{name: "path without slash", mutate: func(c *Config) { c.Path = "mcp" }, wantErr: true},
		{name: "healthz path", mutate: func(c *Config) { c.Path = "/healthz" }, wantErr: true},
		{name: "zero timeout", mutate: func(c *Config) { c.Timeout = 0 }, wantErr: true},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			cfg := valid()
			if tt.mutate != nil {
				tt.mutate(&cfg)
			}
			if gotErr := cfg.Validate() != nil; gotErr != tt.wantErr {
				t.Fatalf("Validate() error = %v, wantErr %v", cfg.Validate(), tt.wantErr)
			}
		})
	}
}