#!/usr/bin/env luash
-- Luash Showcase: Highlight the best features

print("🚀 Luash - Minimal Lua Shell Scripting")
print("=" .. string.rep("=", 45))

print("\n💡 Why Luash?")
print("✓ Clean syntax - no more bash quoting nightmares")
print("✓ Real programming language features")  
print("✓ Seamless shell integration")
print("✓ Minimal and focused")

print("\n📊 Quick Comparison:")
print("┌─────────────────┬─────────────────────┬─────────────────────┐")
print("│ Task            │ Bash                │ Luash               │")
print("├─────────────────┼─────────────────────┼─────────────────────┤")
print("│ Variables       │ VAR=\"value\"         │ $VAR = \"value\"      │")
print("│ Command Sub     │ result=$(cmd)       │ result = `cmd`      │")
print("│ Conditionals    │ if [ -f file ]; fi  │ if `test -f file`   │")
print("│ Arrays          │ arr=(a b c)         │ arr = {\"a\",\"b\",\"c\"} │")
print("│ Functions       │ Limited             │ Full Lua functions  │")
print("└─────────────────┴─────────────────────┴─────────────────────┘")

print("\n🎯 Live Examples:")

print("\n1. Environment & Variables")
print("   Current user: " .. $USER)
$GREETING = "Hello from Luash"
print("   Custom var: " .. $GREETING)

print("\n2. Shell Integration")
system_info = `uname -a`
print("   System: " .. system_info)

file_count = `ls | wc -l`
print("   Files here: " .. file_count)

print("\n3. Real Programming")
-- Lua's power: functions, tables, proper data types
function analyze_directory(path)
    local files = `ls -la ` .. (path or ".")
    local lines = {}
    local file_count = 0
    local total_size = 0
    
    for line in files:gmatch("[^\n]+") do
        if not line:match("^total") and not line:match("^d") then
            file_count = file_count + 1
            -- Extract size (5th field in ls -la)
            local size = line:match("%S+%s+%S+%s+%S+%s+%S+%s+(%d+)")
            if size then
                total_size = total_size + tonumber(size)
            end
        end
    end
    
    return file_count, total_size
end

files, size = analyze_directory()
print("   Analysis: " .. files .. " files, " .. size .. " bytes total")

print("\n4. Error Handling")
if `which git 2>/dev/null` ~= "" then
    print("   ✓ Git is available")
    if `git status 2>/dev/null` ~= "" then
        branch = `git branch --show-current 2>/dev/null`
        print("   Current branch: " .. branch)
    else
        print("   Not in a git repository")
    end
else
    print("   ✗ Git not installed")
end

print("\n5. Data Processing")
-- Create and process some data
sample_data = {
    {name = "Alice", score = 95},
    {name = "Bob", score = 87}, 
    {name = "Charlie", score = 92}
}

total_score = 0
for i = 1, #sample_data do
    total_score = total_score + sample_data[i].score
end
average = total_score / #sample_data

print("   Student scores processed:")
print("   Average: " .. string.format("%.1f", average))

-- Find highest scorer
best_student = sample_data[1]
for i = 2, #sample_data do
    if sample_data[i].score > best_student.score then
        best_student = sample_data[i]
    end
end
print("   Top student: " .. best_student.name .. " (" .. best_student.score .. ")")

print("\n🎪 Interactive Demo:")
print("   Let's see what's running on your system...")
!ps aux | head -5

print("\n📈 Performance:")
start_time = `date +%s.%N`
-- Simulate some work
for i = 1, 1000 do
    local _ = string.upper("performance test " .. i)
end
end_time = `date +%s.%N`

-- Calculate duration (requires bash-style arithmetic)
duration = tonumber(end_time) - tonumber(start_time)
print("   Processed 1000 operations in " .. string.format("%.3f", duration) .. " seconds")

print("\n✨ Try these demos:")
print("   ./luash demo_quick_examples.luash  # Side-by-side with bash")
print("   ./luash demo_system_admin.luash    # Sysadmin tasks")
print("   ./luash demo_development.luash     # Dev workflows") 
print("   ./luash demo_data_processing.luash # Data analysis")

print("\n🎉 Luash: Shell scripting that doesn't make you cry!")