package handlers

import (
	"bookmann/internal/database"
	"net/http"
	"strconv"

	"github.com/google/uuid"
	"github.com/jackc/pgx/v5/pgtype"
	"github.com/labstack/echo/v4"
)

type Handler struct {
	db *database.Queries
}

func NewHandler(db *database.Queries) *Handler {
	return &Handler{
		db: db,
	}
}

func SetupRoutes(g *echo.Group, db *database.Queries) {
	h := NewHandler(db)

	g.GET("/ebooks", h.ListEbooks)
	g.GET("/ebooks/:id", h.GetEbook)
	g.POST("/ebooks", h.CreateEbook)
	g.PUT("/ebooks/:id", h.UpdateEbook)
	g.DELETE("/ebooks/:id", h.DeleteEbook)

	g.GET("/ebooks/:id/progress", h.GetReadingProgress)
	g.PUT("/ebooks/:id/progress", h.UpdateReadingProgress)
}

// ListEbooks handles GET /api/ebooks
func (h *Handler) ListEbooks(c echo.Context) error {
	limitStr := c.QueryParam("limit")
	offsetStr := c.QueryParam("offset")

	limit := int32(20) // default
	if limitStr != "" {
		if l, err := strconv.Atoi(limitStr); err == nil {
			limit = int32(l)
		}
	}

	offset := int32(0)
	if offsetStr != "" {
		if o, err := strconv.Atoi(offsetStr); err == nil {
			offset = int32(o)
		}
	}

	ebooks, err := h.db.ListEbooks(c.Request().Context(), database.ListEbooksParams{
		Limit:  limit,
		Offset: offset,
	})
	if err != nil {
		return c.JSON(http.StatusInternalServerError, map[string]string{"error": err.Error()})
	}

	return c.JSON(http.StatusOK, ebooks)
}

// GetEbook handles GET /api/ebooks/:id
func (h *Handler) GetEbook(c echo.Context) error {
	idStr := c.Param("id")
	id, err := uuid.Parse(idStr)
	if err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid id"})
	}

	ebook, err := h.db.GetEbook(c.Request().Context(), pgtype.UUID{Bytes: id, Valid: true})
	if err != nil {
		return c.JSON(http.StatusInternalServerError, map[string]string{"error": err.Error()})
	}

	return c.JSON(http.StatusOK, ebook)
}

// CreateEbookRequest represents the request for creating an ebook
type CreateEbookRequest struct {
	Title          string `json:"title" validate:"required,min=1,max=500"`
	Author         string `json:"author"`
	ISBN           string `json:"isbn"`
	Description    string `json:"description"`
	FilePath       string `json:"file_path" validate:"required"`
	FileSize       int64  `json:"file_size" validate:"required,min=1"`
	MimeType       string `json:"mime_type" validate:"required"`
	CoverImagePath string `json:"cover_image_path"`
}

// CreateEbook handles POST /api/ebooks
func (h *Handler) CreateEbook(c echo.Context) error {
	var req CreateEbookRequest

	if err := c.Bind(&req); err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid request"})
	}
	if err := c.Validate(&req); err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": err.Error()})
	}

	ebook, err := h.db.CreateEbook(c.Request().Context(), database.CreateEbookParams{
		Title:          req.Title,
		Author:         pgtype.Text{String: req.Author, Valid: req.Author != ""},
		Isbn:           pgtype.Text{String: req.ISBN, Valid: req.ISBN != ""},
		Description:    pgtype.Text{String: req.Description, Valid: req.Description != ""},
		FilePath:       req.FilePath,
		FileSize:       pgtype.Int8{Int64: req.FileSize, Valid: req.FileSize > 0},
		MimeType:       pgtype.Text{String: req.MimeType, Valid: req.MimeType != ""},
		CoverImagePath: pgtype.Text{String: req.CoverImagePath, Valid: req.CoverImagePath != ""},
	})
	if err != nil {
		return c.JSON(http.StatusInternalServerError, map[string]string{"error": err.Error()})
	}

	return c.JSON(http.StatusCreated, ebook)
}

// UpdateEbookRequest represents the request for updating an ebook
type UpdateEbookRequest struct {
	Title          string `json:"title" validate:"required,min=1,max=500"`
	Author         string `json:"author"`
	ISBN           string `json:"isbn"`
	Description    string `json:"description"`
	CoverImagePath string `json:"cover_image_path"`
}

// UpdateEbook handles PUT /api/ebooks/:id
func (h *Handler) UpdateEbook(c echo.Context) error {
	idStr := c.Param("id")
	id, err := uuid.Parse(idStr)
	if err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid id"})
	}

	var req UpdateEbookRequest

	if err := c.Bind(&req); err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid request"})
	}
	if err := c.Validate(&req); err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": err.Error()})
	}

	ebook, err := h.db.UpdateEbook(c.Request().Context(), database.UpdateEbookParams{
		ID:             pgtype.UUID{Bytes: id, Valid: true},
		Title:          req.Title,
		Author:         pgtype.Text{String: req.Author, Valid: req.Author != ""},
		Isbn:           pgtype.Text{String: req.ISBN, Valid: req.ISBN != ""},
		Description:    pgtype.Text{String: req.Description, Valid: req.Description != ""},
		CoverImagePath: pgtype.Text{String: req.CoverImagePath, Valid: req.CoverImagePath != ""},
	})
	if err != nil {
		return c.JSON(http.StatusInternalServerError, map[string]string{"error": err.Error()})
	}

	return c.JSON(http.StatusOK, ebook)
}

// DeleteEbook handles DELETE /api/ebooks/:id
func (h *Handler) DeleteEbook(c echo.Context) error {
	idStr := c.Param("id")
	id, err := uuid.Parse(idStr)
	if err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid id"})
	}

	err = h.db.DeleteEbook(c.Request().Context(), pgtype.UUID{Bytes: id, Valid: true})
	if err != nil {
		return c.JSON(http.StatusInternalServerError, map[string]string{"error": err.Error()})
	}

	return c.NoContent(http.StatusNoContent)
}

// GetReadingProgress handles GET /api/ebooks/:id/progress
func (h *Handler) GetReadingProgress(c echo.Context) error {
	ebookIdStr := c.Param("id")
	userID := c.Get("user_id").(string)

	ebookId, err := uuid.Parse(ebookIdStr)
	if err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid ebook id"})
	}

	userUUID, err := uuid.Parse(userID)
	if err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid user"})
	}

	progress, err := h.db.GetReadingProgress(c.Request().Context(), database.GetReadingProgressParams{
		EbookID: pgtype.UUID{Bytes: ebookId, Valid: true},
		UserID:  pgtype.UUID{Bytes: userUUID, Valid: true},
	})
	if err != nil {
		// If no progress found, return default
		return c.JSON(http.StatusOK, map[string]interface{}{
			"ebook_id":     ebookIdStr,
			"user_id":      userID,
			"current_page": 0,
			"total_pages":  nil,
		})
	}

	return c.JSON(http.StatusOK, progress)
}

// UpdateReadingProgressRequest represents the request for updating reading progress
type UpdateReadingProgressRequest struct {
	CurrentPage int32 `json:"current_page" validate:"required,min=0"`
	TotalPages  int32 `json:"total_pages" validate:"omitempty,min=1"`
}

// UpdateReadingProgress handles PUT /api/ebooks/:id/progress
func (h *Handler) UpdateReadingProgress(c echo.Context) error {
	ebookIdStr := c.Param("id")
	userID := c.Get("user_id").(string)

	ebookId, err := uuid.Parse(ebookIdStr)
	if err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid ebook id"})
	}

	userUUID, err := uuid.Parse(userID)
	if err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid user"})
	}

	var req UpdateReadingProgressRequest

	if err := c.Bind(&req); err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid request"})
	}
	if err := c.Validate(&req); err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": err.Error()})
	}

	progress, err := h.db.UpdateReadingProgress(c.Request().Context(), database.UpdateReadingProgressParams{
		EbookID:     pgtype.UUID{Bytes: ebookId, Valid: true},
		UserID:      pgtype.UUID{Bytes: userUUID, Valid: true},
		CurrentPage: pgtype.Int4{Int32: req.CurrentPage, Valid: true},
		TotalPages:  pgtype.Int4{Int32: req.TotalPages, Valid: req.TotalPages > 0},
	})
	if err != nil {
		return c.JSON(http.StatusInternalServerError, map[string]string{"error": err.Error()})
	}

	return c.JSON(http.StatusOK, progress)
}