package main

import (
	"fmt"
	"os"
	"regexp"
	"strings"
)

// handleSet sets a shell variable
func (c *KVSClient) handleSet(args []string) {
	if len(args) < 2 {
		fmt.Println(red("Usage: set <name> <value>"))
		fmt.Println("Example: set USER_ID abc-123")
		return
	}

	name := args[0]
	value := strings.Join(args[1:], " ")

	c.variables[name] = value
	fmt.Printf(green("Set:")+" %s = %s\n", name, value)
}

// handleUnset removes a shell variable
func (c *KVSClient) handleUnset(args []string) {
	if len(args) < 1 {
		fmt.Println(red("Usage: unset <name>"))
		return
	}

	name := args[0]
	if _, exists := c.variables[name]; exists {
		delete(c.variables, name)
		fmt.Println(green("Unset:"), name)
	} else {
		fmt.Println(yellow("Variable not set:"), name)
	}
}

// handleVars lists all shell variables
func (c *KVSClient) handleVars(args []string) {
	if len(c.variables) == 0 {
		fmt.Println(yellow("No variables set"))
		return
	}

	fmt.Println(cyan("Shell Variables:"))
	for name, value := range c.variables {
		fmt.Printf("  %s = %s\n", name, value)
	}
}

// expandVariables performs variable substitution on a string
// Supports:
// - $VAR or ${VAR} for shell variables
// - $ENV:VAR for environment variables
func (c *KVSClient) expandVariables(input string) string {
	// Pattern for $VAR or ${VAR}
	varPattern := regexp.MustCompile(`\$\{?([A-Za-z_][A-Za-z0-9_]*)\}?`)

	// Pattern for $ENV:VAR
	envPattern := regexp.MustCompile(`\$ENV:([A-Za-z_][A-Za-z0-9_]*)`)

	// First, replace environment variables
	result := envPattern.ReplaceAllStringFunc(input, func(match string) string {
		varName := envPattern.FindStringSubmatch(match)[1]
		if value, exists := os.LookupEnv(varName); exists {
			return value
		}
		return match // Leave unchanged if not found
	})

	// Then, replace shell variables
	result = varPattern.ReplaceAllStringFunc(result, func(match string) string {
		varName := varPattern.FindStringSubmatch(match)[1]
		if value, exists := c.variables[varName]; exists {
			return value
		}
		return match // Leave unchanged if not found
	})

	return result
}