package environment

import (
	"context"
	"fmt"
	"os"
	"path/filepath"
)

// Environment manages Wild Cloud environment variables and paths
type Environment struct {
	wcRoot string
	wcHome string
}

// New creates a new Environment instance
func New() *Environment {
	env := &Environment{}

	// Initialize from environment variables set by root command
	if wcRoot := os.Getenv("WC_ROOT"); wcRoot != "" {
		env.wcRoot = wcRoot
	}
	if wcHome := os.Getenv("WC_HOME"); wcHome != "" {
		env.wcHome = wcHome
	}

	// If WC_HOME is not set, try to detect it
	if env.wcHome == "" {
		if detected, err := env.DetectWCHome(); err == nil && detected != "" {
			env.wcHome = detected
			// Set environment variable for child processes
			_ = os.Setenv("WC_HOME", detected)
		}
	}

	return env
}

// WCRoot returns the Wild Cloud installation directory
func (e *Environment) WCRoot() string {
	return e.wcRoot
}

// WCHome returns the Wild Cloud project directory
func (e *Environment) WCHome() string {
	return e.wcHome
}

// SetWCRoot sets the Wild Cloud installation directory
func (e *Environment) SetWCRoot(path string) {
	e.wcRoot = path
}

// SetWCHome sets the Wild Cloud project directory
func (e *Environment) SetWCHome(path string) {
	e.wcHome = path
}

// DetectWCHome attempts to find the Wild Cloud project directory by looking for .wildcloud marker
func (e *Environment) DetectWCHome() (string, error) {
	// Start from current working directory
	dir, err := os.Getwd()
	if err != nil {
		return "", fmt.Errorf("getting current directory: %w", err)
	}

	// Walk up the directory tree looking for .wildcloud marker
	for {
		markerPath := filepath.Join(dir, ".wildcloud")
		if info, err := os.Stat(markerPath); err == nil && info.IsDir() {
			return dir, nil
		}

		parent := filepath.Dir(dir)
		if parent == dir {
			// Reached root directory
			break
		}
		dir = parent
	}

	return "", nil
}

// Validate checks that the environment is properly configured
func (e *Environment) Validate(ctx context.Context) error {
	// Validate WC_ROOT if set
	if e.wcRoot != "" {
		if err := e.validateWCRoot(); err != nil {
			return fmt.Errorf("invalid WC_ROOT: %w", err)
		}
	}

	// Validate WC_HOME if set
	if e.wcHome != "" {
		if err := e.validateWCHome(); err != nil {
			return fmt.Errorf("invalid WC_HOME: %w", err)
		}
	}

	return nil
}

// validateWCRoot checks that WC_ROOT is a valid Wild Cloud installation
func (e *Environment) validateWCRoot() error {
	if e.wcRoot == "" {
		return nil
	}

	// Check if directory exists
	info, err := os.Stat(e.wcRoot)
	if err != nil {
		return fmt.Errorf("directory does not exist: %w", err)
	}
	if !info.IsDir() {
		return fmt.Errorf("path is not a directory: %s", e.wcRoot)
	}

	// Check for bin directory (contains wild-* scripts)
	binDir := filepath.Join(e.wcRoot, "bin")
	if info, err := os.Stat(binDir); err != nil || !info.IsDir() {
		return fmt.Errorf("bin directory not found, this may not be a Wild Cloud installation")
	}

	// Note: We skip the PATH check for CLI usage as it's not required
	// The original bash scripts expect WC_ROOT/bin to be in PATH, but the CLI can work without it

	return nil
}

// validateWCHome checks that WC_HOME is a valid Wild Cloud project
func (e *Environment) validateWCHome() error {
	if e.wcHome == "" {
		return nil
	}

	// Check if directory exists
	info, err := os.Stat(e.wcHome)
	if err != nil {
		return fmt.Errorf("directory does not exist: %w", err)
	}
	if !info.IsDir() {
		return fmt.Errorf("path is not a directory: %s", e.wcHome)
	}

	// Check for .wildcloud marker directory
	markerDir := filepath.Join(e.wcHome, ".wildcloud")
	if info, err := os.Stat(markerDir); err != nil || !info.IsDir() {
		return fmt.Errorf("not a Wild Cloud project directory (missing .wildcloud marker)")
	}

	return nil
}

// ConfigPath returns the path to the config.yaml file
func (e *Environment) ConfigPath() string {
	if e.wcHome == "" {
		return ""
	}
	return filepath.Join(e.wcHome, "config.yaml")
}

// SecretsPath returns the path to the secrets.yaml file
func (e *Environment) SecretsPath() string {
	if e.wcHome == "" {
		return ""
	}
	return filepath.Join(e.wcHome, "secrets.yaml")
}

// AppsDir returns the path to the apps directory
func (e *Environment) AppsDir() string {
	if e.wcHome == "" {
		return ""
	}
	return filepath.Join(e.wcHome, "apps")
}

// WildCloudDir returns the path to the .wildcloud directory
func (e *Environment) WildCloudDir() string {
	if e.wcHome == "" {
		return ""
	}
	return filepath.Join(e.wcHome, ".wildcloud")
}

// CacheDir returns the path to the cache directory
func (e *Environment) CacheDir() string {
	if e.wcHome == "" {
		return ""
	}
	return filepath.Join(e.wcHome, ".wildcloud", "cache")
}

// IsConfigured returns true if both WC_ROOT and WC_HOME are set and valid
func (e *Environment) IsConfigured() bool {
	return e.wcRoot != "" && e.wcHome != ""
}

// RequiresProject returns an error if WC_HOME is not configured
func (e *Environment) RequiresProject() error {
	if e.wcHome == "" {
		return fmt.Errorf("this command requires a Wild Cloud project directory. Run 'wild setup scaffold' to create one, or run from within an existing project")
	}
	return nil
}

// RequiresInstallation returns an error if WC_ROOT is not configured
func (e *Environment) RequiresInstallation() error {
	if e.wcRoot == "" {
		return fmt.Errorf("WC_ROOT is not set. Please set the WC_ROOT environment variable to your Wild Cloud installation directory")
	}
	return nil
}