module Tina4::Template

def add_global(key, value) 

def add_global(key, value)
  globals[key.to_s] = value
end

def default_error_html(code) 

def default_error_html(code)
  messages = { 403 => "Forbidden", 404 => "Not Found", 500 => "Internal Server Error" }
  msg = messages[code] || "Error"
  colors = { 403 => "#f59e0b", 404 => "#3b82f6", 500 => "#ef4444" }
  color = colors[code] || "#ef4444"
  <<~HTML
    <!DOCTYPE html>
    <html lang="en">
    #{error_overlay_head("#{code} — #{msg}")}
    <body>
    #{error_overlay_css(color)}
    <div class="error-card">
        <div class="logo">T4</div>
        <div class="error-code">#{code}</div>
        <div class="error-title">#{msg}</div>
        <div class="error-msg">Something went wrong while processing your request.</div>
        <a href="/" class="error-home">Go Home</a>
    </div>
    </body>
    </html>
  HTML
end

def error_overlay_css(color) 

def error_overlay_css(color)
  <<~CSS
    <style>
    * { box-sizing: border-box; margin: 0; padding: 0; }
    body { font-family: system-ui, -apple-system, sans-serif; background: #0f172a; color: #e2e8f0; min-height: 100vh; display: flex; align-items: center; justify-content: center; }
    .error-card { background: #1e293b; border: 1px solid #334155; border-radius: 1rem; padding: 3rem; text-align: center; max-width: 520px; width: 90%; }
    .error-code { font-size: 8rem; font-weight: 900; color: #{color}; opacity: 0.6; line-height: 1; margin-bottom: 0.5rem; }
    .error-title { font-size: 1.5rem; font-weight: 700; margin-bottom: 0.75rem; }
    .error-msg { color: #94a3b8; font-size: 1rem; margin-bottom: 1.5rem; line-height: 1.5; }
    .error-home { display: inline-block; padding: 0.6rem 2rem; background: #3b82f6; color: #fff; text-decoration: none; border-radius: 0.5rem; font-size: 0.9rem; font-weight: 600; }
    .error-home:hover { opacity: 0.9; }
    .logo { font-size: 1.5rem; margin-bottom: 1rem; opacity: 0.5; }
    </style>
  CSS
end

def error_overlay_env 

def error_overlay_env
  "<div class=\"env-info\">Ruby #{RUBY_VERSION} | Tina4</div>"
end

def error_overlay_head(title) 

def error_overlay_head(title)
  <<~HEAD
    <head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <title>#{title}</title>
    </head>
  HEAD
end

def error_overlay_request(env) 

def error_overlay_request(env)
  return "" unless env.is_a?(Hash)
  method = env["REQUEST_METHOD"] || "?"
  path = env["PATH_INFO"] || "?"
  "<div class=\"request-info\"><strong>#{method}</strong> #{path}</div>"
end

def error_overlay_source(file, line) 

def error_overlay_source(file, line)
  return "" unless file && line && File.exist?(file)
  lines = File.readlines(file)
  start = [line.to_i - 4, 0].max
  finish = [line.to_i + 3, lines.length - 1].min
  snippet = lines[start..finish].each_with_index.map do |l, i|
    num = start + i + 1
    "<div class=\"source-line#{num == line.to_i ? ' highlight' : ''}\"><span class=\"line-num\">#{num}</span>#{l.chomp}</div>"
  end.join("\n")
  "<pre class=\"source-context\">#{snippet}</pre>"
end

def error_overlay_stacktrace(exception) 

def error_overlay_stacktrace(exception)
  return "" unless exception.respond_to?(:backtrace) && exception.backtrace
  lines = exception.backtrace.map { |l| "<li>#{l}</li>" }.join("\n")
  "<ul class=\"stacktrace\">#{lines}</ul>"
end

def globals 

def globals
  @globals ||= {}
end

def render(template_path, data = {}) 

def render(template_path, data = {})
  full_path = resolve_path(template_path)
  unless full_path && File.exist?(full_path)
    raise "Template not found: #{template_path}"
  end
  content = File.read(full_path)
  ext = File.extname(full_path).downcase
  context = globals.merge(data.transform_keys(&:to_s))
  case ext
  when ".twig", ".html", ".tina4"
    TwigEngine.new(context, File.dirname(full_path)).render(content)
  when ".erb"
    ErbEngine.render(content, context)
  else
    TwigEngine.new(context, File.dirname(full_path)).render(content)
  end
end

def render_error(code, data = {}) 

def render_error(code, data = {})
  error_dirs = TEMPLATE_DIRS.map { |d| File.join(Dir.pwd, d, "errors") }
  error_dirs << File.join(File.dirname(__FILE__), "templates", "errors")
  context = { "code" => code }.merge(data.transform_keys(&:to_s))
  error_dirs.each do |dir|
    %w[.twig .html .erb].each do |ext|
      path = File.join(dir, "#{code}#{ext}")
      if File.exist?(path)
        content = File.read(path)
        return TwigEngine.new(context, dir).render(content)
      end
    end
  end
  default_error_html(code)
end

def resolve_path(template_path) 

def resolve_path(template_path)
  return template_path if File.exist?(template_path)
  TEMPLATE_DIRS.each do |dir|
    full = File.join(Dir.pwd, dir, template_path)
    return full if File.exist?(full)
  end
  gem_templates = File.join(File.dirname(__FILE__), "templates")
  full = File.join(gem_templates, template_path)
  return full if File.exist?(full)
  nil
end