// Raw strings and reusable templates
// Demonstrates raw keyword and template() builtin

print("=== RAW KEYWORD - Prevent Template Evaluation ===\n")

// Normal string - templates are evaluated
name = "Alice"
normal = "Hello {{name}}"
print("Normal: " + normal)  // Output: Hello Alice

// Raw string - templates NOT evaluated
raw_str = raw "Hello {{name}}"
print("Raw:    " + raw_str)  // Output: Hello {{name}}

print("\n=== TEMPLATE() - Reusable Templates ===\n")

// Create a template function
greeting_template = template("Hello {{name}}, welcome to {{place}}!")

// Evaluate with different values
greet1 = greeting_template(name = "Alice", place = "Duso")
greet2 = greeting_template(name = "Bob", place = "the AI workshop")

print(greet1)  // Hello Alice, welcome to Duso!
print(greet2)  // Hello Bob, welcome to the AI workshop!

print("\n=== PATTERN: Store & Reuse ===\n")

// Store template pattern without evaluating (using raw)
invoice_pattern = raw """
Invoice #{{invoice_id}}
Customer: {{customer_name}}
Date: {{date}}
Amount: ${{amount}}
Status: {{status}}
"""

// Create template function from the pattern
invoice_gen = template(invoice_pattern)

// Generate multiple invoices
inv1 = invoice_gen(
  invoice_id = "INV-001",
  customer_name = "Alice Corp",
  date = "2025-01-30",
  amount = 1500.00,
  status = "Paid"
)

inv2 = invoice_gen(
  invoice_id = "INV-002",
  customer_name = "Bob Industries",
  date = "2025-01-30",
  amount = 2500.00,
  status = "Pending"
)

print(inv1)
print("\n")
print(inv2)

print("\n=== EXPRESSION EVALUATION IN TEMPLATES ===\n")

// Templates can include expressions
calc = template("Result: {{x}} + {{y}} = {{x + y}}")
result = calc(x = 10, y = 20)
print(result)  // Result: 10 + 20 = 30

// With object access
person = {name = "Charlie", age = 35}
profile = template("Name: {{p.name}}, Age: {{p.age}}, Next year: {{p.age + 1}}")
output = profile(p = person)
print(output)  // Name: Charlie, Age: 35, Next year: 36

print("\n=== PRACTICAL: Email Template Builder ===\n")

// Define reusable email templates
order_email = template(raw """
Dear {{customer}},

Thank you for your order!

Order Details:
- Order ID: {{order_id}}
- Items: {{items}}
- Total: ${{total}}

Your order will be shipped within 2-3 business days.

Best regards,
Order Management Team
""")

// Send emails to different customers
email1 = order_email(
  customer = "Alice",
  order_id = "ORD-12345",
  items = "Widget x2, Gadget x1",
  total = 99.99
)

email2 = order_email(
  customer = "Bob",
  order_id = "ORD-12346",
  items = "Widget x5",
  total = 149.95
)

print("Email 1:")
print(email1)
print("\n")
print("Email 2:")
print(email2)

print("\n=== RAW WITH MULTILINE STRINGS ===\n")

// Raw prevents evaluation even in multiline strings
config_template = raw """
{
  "app": "MyApp",
  "user": "{{username}}",
  "role": "{{user_role}}",
  "permissions": ["read", "write"],
  "login_time": "{{now()}}",
  "settings": {
    "theme": "{{theme}}",
    "language": "{{lang}}"
  }
}
"""

print("Stored JSON template (unevaluated):")
print(config_template)

// Now create template to use later
config_gen = template(config_template)
config = config_gen(
  username = "alice_smith",
  user_role = "admin",
  theme = "dark",
  lang = "en"
)

print("\nEvaluated config:")
print(config)

print("\n=== TEMPLATE PATTERN STORAGE ===\n")

// Store template pattern as raw string, then create function later
// This avoids evaluating the template prematurely
email_pattern = raw """
Hi {{recipient}},

We hope you enjoy {{product}}!

Special offer: {{discount}}% off your next purchase.

Cheers,
The Team
"""

// Convert to template function
offer_email = template(email_pattern)

// Use the template multiple times
msg1 = offer_email(recipient = "Diana", product = "the Duso manual", discount = 10)
msg2 = offer_email(recipient = "Eve", product = "our AI training course", discount = 15)

print("Message 1:")
print(msg1)
print("\n")
print("Message 2:")
print(msg2)