// Command server is the GitManager entrypoint. It wires config, logging, the
// Git boundary, the repo scanner, and the Echo HTTP server, then serves the
// dashboard shell and the JSON endpoints the web components fetch from.
package main

import (
	"context"
	"net/http"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/labstack/echo/v4"
	"github.com/labstack/echo/v4/middleware"

	"gitmanager/internal/config"
	"gitmanager/internal/git"
	"gitmanager/internal/logging"
	mcpserver "gitmanager/internal/mcp"
	"gitmanager/internal/render"
	"gitmanager/internal/repos"
	"gitmanager/internal/service"
)

func main() {
	cfg, err := config.Load()
	if err != nil {
		panic(err)
	}

	log, closer, err := logging.Setup(cfg.Dev, cfg.LogFile)
	if err != nil {
		panic(err)
	}
	if closer != nil {
		defer closer.Close()
	}

	g := git.New(cfg.GitBin)
	if v, err := g.Version(context.Background()); err != nil {
		log.Warn("git binary not usable — repo operations will fail", "bin", cfg.GitBin, "err", err)
	} else {
		log.Info("git detected", "version", v)
	}

	// Start the read-only scanner in the background.
	scanner := repos.NewScanner(g, log, cfg.RepoRoots, cfg.ScanMaxDepth, cfg.ScanIgnore, cfg.ScanInterval, cfg.ScanFetchEnabled)
	scanCtx, stopScan := context.WithCancel(context.Background())
	defer stopScan()
	go scanner.Run(scanCtx)
	log.Info("scanner started", "roots", cfg.RepoRoots, "interval", cfg.ScanInterval.String(), "fetch", cfg.ScanFetchEnabled)

	// The one service layer both the HTTP API and the MCP server call (§1.7).
	svc := service.New(g, scanner.Index)

	tmpl, err := render.New("web/templates")
	if err != nil {
		log.Error("failed to parse templates", "err", err)
		os.Exit(1)
	}

	e := echo.New()
	e.HideBanner = true
	e.Renderer = tmpl
	e.Use(middleware.Recover())
	e.Use(middleware.RequestID())

	// Static assets and component sources.
	e.Static("/static", "web/static")
	e.Static("/components", "components")

	// Page shells.
	e.GET("/", func(c echo.Context) error {
		return c.Render(http.StatusOK, "index.html", nil)
	})
	e.GET("/help", func(c echo.Context) error {
		return c.Render(http.StatusOK, "help.html", nil)
	})

	// JSON API — components self-fetch from here.
	e.GET("/healthz", func(c echo.Context) error {
		return c.JSON(http.StatusOK, map[string]string{"status": "ok"})
	})
	e.GET("/api/repos", func(c echo.Context) error {
		return c.JSON(http.StatusOK, svc.ListRepos())
	})
	e.GET("/api/repo", func(c echo.Context) error {
		// The service only serves details for an already-discovered repo — it
		// never runs git against an arbitrary caller-supplied path (§1.3).
		detail, ok := svc.RepoDetail(c.Request().Context(), c.QueryParam("path"))
		if !ok {
			return c.JSON(http.StatusNotFound, map[string]string{"error": "unknown repository"})
		}
		return c.JSON(http.StatusOK, detail)
	})

	// MCP server — Claude connects here as a custom connector (§8.1). Same
	// service layer as the HTTP API (§1.7); localhost-bound like everything else.
	mcpSrv := mcpserver.NewServer(svc, "0.1.0")
	e.Any("/mcp", echo.WrapHandler(mcpserver.Handler(mcpSrv)))
	log.Info("mcp server mounted", "path", "/mcp")

	// Serve with graceful shutdown.
	go func() {
		if err := e.Start(cfg.ListenAddr); err != nil && err != http.ErrServerClosed {
			log.Error("server error", "err", err)
			os.Exit(1)
		}
	}()
	log.Info("listening", "addr", cfg.ListenAddr)

	// Optional HTTPS listener (same Echo app). Required for the MCP connector,
	// which only accepts https:// URLs (§8.1). Best-effort: a missing/unreadable
	// cert logs a warning and leaves the app running over HTTP.
	if cfg.HTTPSAddr != "" && cfg.TLSCertFile != "" && cfg.TLSKeyFile != "" {
		if _, err := os.Stat(cfg.TLSCertFile); err != nil {
			log.Warn("HTTPS requested but cert not readable — serving HTTP only", "cert", cfg.TLSCertFile, "err", err)
		} else {
			go func() {
				if err := e.StartTLS(cfg.HTTPSAddr, cfg.TLSCertFile, cfg.TLSKeyFile); err != nil && err != http.ErrServerClosed {
					log.Error("TLS server error", "err", err)
				}
			}()
			log.Info("listening (https)", "addr", cfg.HTTPSAddr)
		}
	}

	quit := make(chan os.Signal, 1)
	signal.Notify(quit, os.Interrupt, syscall.SIGTERM)
	<-quit
	log.Info("shutting down")

	stopScan()
	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()
	if err := e.Shutdown(ctx); err != nil {
		log.Error("graceful shutdown failed", "err", err)
	}
}