//go:build mage

package main

import (
	"fmt"
	"os"
	"path/filepath"
	"strings"

	"codeflow.dananglin.me.uk/linux-home/manager/magefiles/internal/config"
	"codeflow.dananglin.me.uk/linux-home/manager/magefiles/internal/utilities"
	"codeflow.dananglin.me.uk/linux-home/manager/magefiles/internal/walk"
)

// Templates generates the configuration files in the managed directory from the templates and
// ensures that they the generated files are symlinked correctly to the files in the user's home
// configuration directory.
func Templates() error {
	const rootTemplateDir string = "templates"

	homeConfigDirectory, err := os.UserConfigDir()
	if err != nil {
		return fmt.Errorf("unable to get the user's home configuration directory: %w", err)
	}

	cfg, err := config.NewConfig()
	if err != nil {
		return fmt.Errorf("unable to load the configuration: %w", err)
	}

	managedConfig := utilities.ManagedConfigSet(cfg.ManagedConfigurations)

	validationFunc := func(relativePath string) bool {
		split := strings.SplitN(relativePath, "/", 2)

		if len(split) < 1 {
			return false
		}

		appConfigName := split[0]

		_, exists := managedConfig[appConfigName]

		return exists
	}

	if err = filepath.WalkDir(
		rootTemplateDir,
		walk.RenderTemplates(
			cfg,
			homeConfigDirectory,
			rootTemplateDir,
			rootManagedDir,
			validationFunc,
		),
	); err != nil {
		return fmt.Errorf("received an error while rendering the templates: %w", err)
	}

	return nil
}