package main

import (
	"fmt"
	"net/http"
	"strings"

	"github.com/nikolalohinski/gonja/v2"
	"github.com/nikolalohinski/gonja/v2/exec"
)

func renderGonja(templateContent string, templatePath string, r *http.Request, extraData map[string]any) (string, error) {
	ctx := buildRequestContext(r, extraData)

	// Use FromFile to support extends/include resolution
	tmpl, err := gonja.FromFile(templatePath)
	if err != nil {
		return "", fmt.Errorf("parsing template %s: %w", templatePath, err)
	}

	// Execute template with context
	result, err := tmpl.ExecuteToString(ctx)
	if err != nil {
		return "", fmt.Errorf("executing template %s: %w", templatePath, err)
	}

	return result, nil
}

func buildRequestContext(r *http.Request, extraData map[string]any) *exec.Context {
	// Parse form data
	form := make(map[string]any)
	if err := r.ParseForm(); err == nil {
		for key, values := range r.Form {
			form[key] = values[0]
		}
	}

	query := make(map[string]any)
	for key, values := range r.URL.Query() {
		if len(values) == 1 {
			query[key] = values[0]
		} else {
			query[key] = values
		}
	}

	headers := make(map[string]any)
	for key, values := range r.Header {
		headers[strings.ToLower(key)] = values[0]
	}

	data := map[string]any{
		"request": map[string]any{
			"method":  r.Method,
			"path":    r.URL.Path,
			"query":   query,
			"form":    form,
			"headers": headers,
		},
		"base_url": fmt.Sprintf("%s://%s", r.URL.Scheme, r.Host),
	}

	// Merge extra data from companion Lua data files
	for k, v := range extraData {
		data[k] = v
	}

	return exec.NewContext(data)
}