// Package app wires discovery, status scanning, and presentation into the
// runnable operations used by the CLI commands.
package app

import (
	"context"
	"fmt"
	"os"
	"time"

	"gitea.oblak.solutions/dimitar/gitFlow/internal/config"
	"gitea.oblak.solutions/dimitar/gitFlow/internal/scanner"
	"gitea.oblak.solutions/dimitar/gitFlow/pkg/status"
)

// App coordinates the components built from the resolved configuration.
type App struct {
	cfg        *config.Config
	discoverer *scanner.Discoverer
	scanner    *scanner.Scanner
	warn       func(format string, args ...any)
}

// New builds an App from a validated configuration.
func New(cfg *config.Config) (*App, error) {
	if err := cfg.Validate(); err != nil {
		return nil, err
	}
	return &App{
		cfg: cfg,
		discoverer: scanner.NewDiscoverer(
			scanner.WithExclude(cfg.Exclude...),
			scanner.WithMaxDepth(cfg.MaxDepth),
		),
		scanner: scanner.NewScanner(scanner.WithWorkers(cfg.Workers)),
		warn: func(format string, args ...any) {
			fmt.Fprintf(os.Stderr, "warning: "+format+"\n", args...)
		},
	}, nil
}

// ScanOnce discovers repositories under the configured directory and
// snapshots their status in a single pass.
func (a *App) ScanOnce(ctx context.Context) (status.ScanResult, error) {
	repos, err := a.discoverer.Discover(ctx, a.cfg.Dir)
	if err != nil {
		if len(repos) == 0 {
			return status.ScanResult{}, err
		}
		// Partial discovery (e.g. permission denied on some subtree):
		// warn and continue with what was found.
		a.warn("%v", err)
	}

	infos, err := a.scanner.Scan(ctx, repos)
	if err != nil {
		return status.ScanResult{}, err
	}
	return status.ScanResult{
		ScannedAt: time.Now(),
		ParentDir: a.cfg.Dir,
		Repos:     infos,
	}, nil
}