package router

import (
	"bytes"
	"context"
	"net/http"
	"time"

	"bookhoard/internal/handlers"
	"bookhoard/templates"

	"github.com/golang-jwt/jwt/v5"
	"github.com/jackc/pgx/v5/pgtype"
	"github.com/labstack/echo/v4"

	"github.com/google/uuid"
)

func registerFrontendRoutes(cfg *Config) {
	e := cfg.Echo

	// ============================================================================
	// FRONTEND ROUTES - DO NOT DELETE
	// These routes serve Server-Side Rendered (SSR) HTML pages for the web UI.
	// They are NOT API endpoints and should NOT be removed during refactors.
	// All authenticated frontend routes use the jwtMiddleware to validate tokens.
	// ============================================================================

	// Use existing JWT middleware (sets database user object in context)
	jwtMiddleware := createJWTMiddleware(cfg)

	// Protected route group for API routes
	protected := e.Group("/api", jwtMiddleware)

	// ============================================================================
	// PUBLIC FRONTEND ROUTES (No authentication required)
	// ============================================================================

	// Public routes for login and registration pages
	e.GET("/login", func(c echo.Context) error {
		var buf bytes.Buffer
		sessionExpired := c.QueryParam("session") == "expired"
		err := templates.Login(sessionExpired).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	})

	e.GET("/register", func(c echo.Context) error {
		var buf bytes.Buffer
		err := templates.Register().Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	})

	// Root route - landing page with smart login detection
	e.GET("/", func(c echo.Context) error {
		var buf bytes.Buffer
		var err error

		tokenString := c.Request().Header.Get("Authorization")
		if tokenString != "" && len(tokenString) > 7 && tokenString[:7] == "Bearer " {
			tokenString = tokenString[7:]
		} else {
			cookie, err := c.Cookie("token")
			if err == nil {
				tokenString = cookie.Value
			}
		}

		loggedIn := false
		if tokenString != "" {
			token, err := jwt.Parse(tokenString, func(token *jwt.Token) (interface{}, error) {
				return []byte(cfg.Cfg.JWTSecret), nil
			})
			loggedIn = err == nil && token.Valid
		}

		err = templates.Index(loggedIn).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	})

	// ============================================================================
	// PROTECTED FRONTEND ROUTES (Authentication required)
	// ============================================================================

	// Protected frontend routes (no /api prefix)
	frontendProtected := e.Group("", jwtMiddleware)

	// Helper to extract text from pgtype.Text
	getText := func(t pgtype.Text) string {
		if t.Valid {
			return t.String
		}
		return ""
	}

	// Dashboard page
	frontendProtected.GET("/dashboard", func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		var buf bytes.Buffer
		err = templates.Dashboard(user).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	})

	// Collections page
	frontendProtected.GET("/collections", func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		collections, err := cfg.CollectionHandler.GetCollectionsData(c)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading collections")
		}
		colData := make([]templates.CollectionData, len(collections))
		for i, col := range collections {
			colData[i] = templates.CollectionData{
				ID:          uuid.UUID(col.ID.Bytes).String(),
				Name:        col.Name,
				Description: getText(col.Description),
				Color:       getText(col.Color),
				Icon:        getText(col.Icon),
			}
		}
		var buf bytes.Buffer
		err = templates.Collection(user, colData).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	})

	// Progress page
	frontendProtected.GET("/progress", func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		progressData, err := cfg.ScannerHandler.GetAllProgressData(c)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading progress")
		}
		var buf bytes.Buffer
		err = templates.Progress(user, progressData).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	})

	// Devices page
	frontendProtected.GET("/devices", func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		devices, err := cfg.DeviceHandler.GetDevicesData(c)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading devices")
		}
		pendingMaps, err := cfg.DeviceHandler.GetPendingRegistrationsData(c)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading pending")
		}
		pendingList := convertPending(pendingMaps)
		var buf bytes.Buffer
		err = templates.Devices(user, devices, pendingList, cfg.Cfg.BaseURL).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	})

	// Conflicts page
	frontendProtected.GET("/conflicts", func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		conflictsData, total, unresolved, err := cfg.ConflictHandler.GetConflictsData(c)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading conflicts")
		}
		var buf bytes.Buffer
		err = templates.Conflicts(user, conflictsData, total, unresolved).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	})

	// Analytics page
	frontendProtected.GET("/analytics", func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		var buf bytes.Buffer
		err = templates.Analytics(user).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	})

	// ============================================================================
	// ADMIN FRONTEND ROUTES
	// ============================================================================

	// Admin routes
	frontendProtected.GET("/admin", handlers.AdminMiddleware(func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		var buf bytes.Buffer
		err = templates.Admin(user).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	}))

	frontendProtected.GET("/admin/", handlers.AdminMiddleware(func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		var buf bytes.Buffer
		err = templates.Admin(user).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	}))

	frontendProtected.GET("/admin/profile", handlers.AdminMiddleware(func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		var buf bytes.Buffer
		err = templates.AdminProfile(user).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	}))

	frontendProtected.GET("/admin/library", handlers.AdminMiddleware(func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		var buf bytes.Buffer
		err = templates.AdminLibrary(user).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	}))

	// ============================================================================
	// LEGACY API ROUTES (for backward compatibility)
	// ============================================================================

	// Keep legacy routes under /api for existing API consumers
	protected.GET("/devices-page", func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		devices, err := cfg.DeviceHandler.GetDevicesData(c)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading devices")
		}
		pendingMaps, err := cfg.DeviceHandler.GetPendingRegistrationsData(c)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading pending")
		}
		pendingList := convertPending(pendingMaps)
		var buf bytes.Buffer
		err = templates.Devices(user, devices, pendingList, cfg.Cfg.BaseURL).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	})

	protected.GET("/conflicts-page", func(c echo.Context) error {
		user, err := getTemplateUserWithTheme(c, cfg)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading user")
		}
		conflictsData, total, unresolved, err := cfg.ConflictHandler.GetConflictsData(c)
		if err != nil {
			return c.HTML(http.StatusInternalServerError, "Error loading conflicts")
		}
		var buf bytes.Buffer
		err = templates.Conflicts(user, conflictsData, total, unresolved).Render(c.Request().Context(), &buf)
		if err != nil {
			return err
		}
		return c.HTML(http.StatusOK, buf.String())
	})

	// ============================================================================
	// HEALTH CHECK
	// ============================================================================

	// Health check
	e.GET("/health", func(c echo.Context) error {
		ctx, cancel := context.WithTimeout(c.Request().Context(), 2*time.Second)
		defer cancel()

		if err := pingDB(cfg, ctx); err != nil {
			return c.JSON(http.StatusServiceUnavailable, map[string]string{
				"status": "unhealthy",
				"error":  "database unavailable",
			})
		}
		return c.JSON(http.StatusOK, map[string]string{
			"status":   "healthy",
			"database": "connected",
		})
	})
}