package server

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

	"task/internal/config"
	"task/internal/project"
	"task/internal/sqlite"
	"task/internal/ticket"
)

// SeedDemoOptions controls optional client wiring during demo seed.
type SeedDemoOptions struct {
	// ClientDataDir, when set, writes local TUI projects (meta.json + tokens)
	// for "Test" and "Website Relaunch" under that data directory.
	ClientDataDir string
	// BaseURL is the tm_server URL stored in client meta (default http://127.0.0.1:8080).
	BaseURL string
}

// tuiSeedProjects are server project names that get a write token and local TUI wiring.
var tuiSeedProjects = []string{"Test", "Website Relaunch"}

// SeedDemo populates sample users/projects/tickets when the DB has no projects yet.
// No external backends (YouTrack etc.) — the web UI talks only to this tm_server.
func (s *Server) SeedDemo(opts SeedDemoOptions) error {
	projects, err := s.Projects.List()
	if err != nil {
		return err
	}
	if len(projects) > 0 {
		return nil
	}

	users, err := s.DB.ListUsers()
	if err != nil {
		return err
	}
	if len(users) == 0 {
		return fmt.Errorf("seed: no users (bootstrap admin first)")
	}
	admin := users[0]
	for _, u := range users {
		if u.IsAdmin {
			admin = u
			break
		}
	}

	member, err := s.DB.CreateUser("alice", "alice", false)
	if err != nil {
		member, err = s.DB.GetUserByUsername("alice")
		if err != nil {
			return fmt.Errorf("seed alice: %w", err)
		}
	}

	type seedTicket struct {
		Title, Desc string
		Status      ticket.Status
	}
	demos := []struct {
		Name    string
		Tickets []seedTicket
	}{
		{
			Name: "Test",
			Tickets: []seedTicket{
				{Title: "Board & Login prüfen", Desc: "Mit admin/admin einloggen, Board öffnen, Status ändern.\n\n- [ ] Login\n- [ ] Ticket editieren\n- [ ] Timer starten", Status: ticket.StatusInProgress},
				{Title: "Zeit auf Ticket buchen", Desc: "Im Ticket-Detail Timer oder manuelle Minuten buchen, dann Report prüfen.", Status: ticket.StatusTodo},
				{Title: "Members & Rechte", Desc: "alice als Member ist schon angelegt — Memberships-Tab ansehen.", Status: ticket.StatusTodo},
				{Title: "TUI Sync", Desc: "Lokal unter `.dev-home` schon mit Token verdrahtet — in `tm` (`make run-dev`) Pull/Push testen.", Status: ticket.StatusTodo},
				{Title: "Seed abgeschlossen", Desc: "Beispiel-Ticket im Status DONE.", Status: ticket.StatusDone},
			},
		},
		{
			Name: "Website Relaunch",
			Tickets: []seedTicket{
				{Title: "Landing Hero entwerfen", Desc: "Dunkles Layout, klare CTAs.\n\n- [ ] Moodboard\n- [ ] Wireframe", Status: ticket.StatusInProgress},
				{Title: "CMS-Inhalte migrieren", Desc: "Alte Seiten nach Markdown überführen.", Status: ticket.StatusTodo},
				{Title: "Impressum & Datenschutz", Desc: "Rechtstexte finalisieren.", Status: ticket.StatusDone},
			},
		},
		{
			Name: "API Platform",
			Tickets: []seedTicket{
				{Title: "Auth-Middleware härten", Desc: "Session-Cookies dokumentieren.", Status: ticket.StatusInProgress},
				{Title: "Rate-Limits festlegen", Desc: "Pro User und pro IP.", Status: ticket.StatusTodo},
				{Title: "Health-Check", Desc: "Bereits live.", Status: ticket.StatusDone},
			},
		},
	}
	for i := len(demos) + 1; i <= 50; i++ {
		demos = append(demos, struct {
			Name    string
			Tickets []seedTicket
		}{
			Name: fmt.Sprintf("Sample %02d", i),
			Tickets: []seedTicket{
				{Title: "Starter ticket", Desc: "Seed-Platzhalter.", Status: ticket.StatusTodo},
			},
		})
	}

	now := time.Now().UTC()
	created := make([]struct{ ID, Name string }, 0, len(demos))
	for _, d := range demos {
		p, err := s.Projects.Create("", d.Name)
		if err != nil {
			return err
		}
		created = append(created, struct{ ID, Name string }{p.ID, p.Name})
		_ = s.DB.SetMember(p.ID, admin.ID, sqlite.RoleOwner)
		_ = s.DB.SetMember(p.ID, member.ID, sqlite.RoleMember)
		// Explicit local-only sync (no remote backend in the test environment).
		_ = s.Projects.SetSyncBackend(sqlite.SyncBackend{
			ProjectID: p.ID,
			Kind:      "none",
		})

		var firstID string
		for i, st := range d.Tickets {
			t, err := s.Tickets.Create(ticket.Ticket{
				Title:       st.Title,
				Description: st.Desc,
				Status:      st.Status,
				ProjectID:   p.ID,
			})
			if err != nil {
				return err
			}
			_, _ = s.DB.AppendRevision("ticket", t.ID, p.ID, "seed", admin.ID, t)
			if i == 0 {
				firstID = t.ID
			}
		}
		if firstID != "" {
			_, err := s.Times.Create(ticket.TimeEntry{
				TicketID:  firstID,
				ProjectID: p.ID,
				Start:     now.Add(-2 * time.Hour),
				End:       now.Add(-90 * time.Minute),
				Duration:  30 * time.Minute,
				Source:    ticket.SourceManual,
				Note:      "seed",
			})
			if err != nil {
				return err
			}
		}
	}

	kunden, err := s.DB.CreateProjectGroup("Kunden")
	if err != nil {
		return fmt.Errorf("seed group Kunden: %w", err)
	}
	intern, err := s.DB.CreateProjectGroup("Intern")
	if err != nil {
		return fmt.Errorf("seed group Intern: %w", err)
	}
	for _, c := range created {
		switch {
		case c.Name == "Website Relaunch" || c.Name == "API Platform" || strings.HasPrefix(c.Name, "Sample 0"):
			_ = s.Projects.SetGroup(c.ID, kunden.ID)
		case c.Name == "Test" || strings.HasPrefix(c.Name, "Sample 1") || strings.HasPrefix(c.Name, "Sample 2"):
			_ = s.Projects.SetGroup(c.ID, intern.ID)
		}
	}

	fmt.Fprintf(os.Stderr, "seeded demo: %d projects, 2 groups (users %s + alice/alice), sync=none\n", len(demos), admin.Username)

	if dir := strings.TrimSpace(opts.ClientDataDir); dir != "" {
		if err := s.wireDemoTUI(dir, opts.BaseURL, created, admin.ID); err != nil {
			return fmt.Errorf("seed tui: %w", err)
		}
	}
	return nil
}

func (s *Server) wireDemoTUI(dataDir, baseURL string, created []struct{ ID, Name string }, adminID string) error {
	baseURL = strings.TrimRight(strings.TrimSpace(baseURL), "/")
	if baseURL == "" {
		baseURL = "http://127.0.0.1:8080"
	}

	byName := make(map[string]string, len(created))
	for _, c := range created {
		byName[c.Name] = c.ID
	}

	store := project.NewDirStore(dataDir)
	wired := make([]string, 0, len(tuiSeedProjects))
	for _, name := range tuiSeedProjects {
		remoteID, ok := byName[name]
		if !ok {
			return fmt.Errorf("missing seeded project %q", name)
		}
		tok, err := s.DB.CreateProjectToken(remoteID, "dev-tui", sqlite.TokenScopeWrite, adminID)
		if err != nil {
			return fmt.Errorf("token for %s: %w", name, err)
		}
		// Fresh local dir so stale tickets from a previous DB wipe cannot confuse sync.
		_ = os.RemoveAll(filepath.Join(dataDir, "projects", name))
		meta := project.Meta{
			Backend: project.BackendTaskMaster,
			TaskMaster: &project.TaskMaster{
				BaseURL:   baseURL,
				Token:     tok.Token,
				ProjectID: remoteID,
			},
		}
		if err := store.SaveMeta(name, meta); err != nil {
			return fmt.Errorf("meta %s: %w", name, err)
		}
		wired = append(wired, name)
		fmt.Fprintf(os.Stderr, "tui wired: %s → %s (project %s, token %s…)\n",
			name, baseURL, remoteID, trimTokenPrefix(tok.Token))
	}

	if err := setActiveProjectIfSameDataDir(dataDir, tuiSeedProjects[0]); err != nil {
		return err
	}
	fmt.Fprintf(os.Stderr, "tui ready: %s (make run-dev → Y pull)\n", strings.Join(wired, ", "))
	return nil
}

func trimTokenPrefix(tok string) string {
	if len(tok) <= 10 {
		return tok
	}
	return tok[:10]
}

func setActiveProjectIfSameDataDir(dataDir, active string) error {
	cfg, err := config.LoadOrCreate()
	if err != nil {
		return fmt.Errorf("config: %w", err)
	}
	if filepath.Clean(cfg.DataDir) != filepath.Clean(dataDir) {
		return nil
	}
	cfg.ActiveProject = active
	if err := config.Save(cfg); err != nil {
		return fmt.Errorf("save config: %w", err)
	}
	return nil
}

// SeedBaseURL derives the public base URL for seeded TUI meta from -listen / env.
func SeedBaseURL(listen string) string {
	if u := strings.TrimSpace(os.Getenv("TM_SEED_BASE_URL")); u != "" {
		return strings.TrimRight(u, "/")
	}
	host := strings.TrimSpace(listen)
	if host == "" {
		host = ":8080"
	}
	switch {
	case strings.HasPrefix(host, "http://"), strings.HasPrefix(host, "https://"):
		return strings.TrimRight(host, "/")
	case strings.HasPrefix(host, ":"):
		return "http://127.0.0.1" + host
	default:
		return "http://" + host
	}
}