package handlers

import (
	"html/template"
	"mealprep/auth"
	"mealprep/database"
	"net/http"
	"strconv"
	"strings"
)

// MealsHandler handles the meals page
func MealsHandler(w http.ResponseWriter, r *http.Request) {
	userID := auth.GetUserID(r)
	meals, err := database.GetAllMeals(userID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	tmpl := `
		<div id="meals-content">
			<h2>Meals</h2>

			<form hx-post="/meals" hx-target="#meals-list" hx-swap="beforeend" class="add-form">
				<input type="text" name="name" placeholder="Meal name" required />
				<input type="text" name="description" placeholder="Description" />
				<select name="meal_type" required>
					<option value="">Select type...</option>
					<option value="breakfast">Breakfast</option>
					<option value="lunch">Lunch</option>
					<option value="snack">Snack</option>
				</select>
				<button type="submit">Add Meal</button>
			</form>

			<div id="meals-list" class="items-list">
				{{range .}}
				<div class="meal-item" id="meal-{{.ID}}">
					<div class="meal-header">
						<div>
							<span class="item-name">{{.Name}}</span>
							<span class="meal-type-tag tag-{{.MealType}}">{{.MealType}}</span>
							<span class="item-description">{{.Description}}</span>
						</div>
						<div>
							<button
								hx-get="/meals/{{.ID}}/ingredients"
								hx-target="#meal-{{.ID}}-ingredients"
								hx-swap="innerHTML"
								class="view-btn">
								View Ingredients
							</button>
							<button
								hx-delete="/meals/{{.ID}}"
								hx-target="#meal-{{.ID}}"
								hx-swap="outerHTML"
								hx-confirm="Are you sure you want to delete this meal?"
								class="delete-btn">
								Delete
							</button>
						</div>
					</div>
					<div id="meal-{{.ID}}-ingredients" class="meal-ingredients"></div>
				</div>
				{{end}}
			</div>
		</div>
	`

	t := template.Must(template.New("meals").Parse(tmpl))
	t.Execute(w, meals)
}

// AddMealHandler handles adding a new meal
func AddMealHandler(w http.ResponseWriter, r *http.Request) {
	userID := auth.GetUserID(r)

	if err := r.ParseForm(); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	name := strings.TrimSpace(r.FormValue("name"))
	description := strings.TrimSpace(r.FormValue("description"))
	mealType := r.FormValue("meal_type")

	if name == "" || mealType == "" {
		http.Error(w, "Name and meal type are required", http.StatusBadRequest)
		return
	}

	// Validate meal type
	if mealType != "breakfast" && mealType != "lunch" && mealType != "snack" {
		http.Error(w, "Invalid meal type", http.StatusBadRequest)
		return
	}

	id, err := database.AddMeal(userID, name, description, mealType)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	tmpl := `
		<div class="meal-item" id="meal-{{.ID}}">
			<div class="meal-header">
				<div>
					<span class="item-name">{{.Name}}</span>
					<span class="meal-type-tag tag-{{.MealType}}">{{.MealType}}</span>
					<span class="item-description">{{.Description}}</span>
				</div>
				<div>
					<button
						hx-get="/meals/{{.ID}}/ingredients"
						hx-target="#meal-{{.ID}}-ingredients"
						hx-swap="innerHTML"
						class="view-btn">
						View Ingredients
					</button>
					<button
						hx-delete="/meals/{{.ID}}"
						hx-target="#meal-{{.ID}}"
						hx-swap="outerHTML"
						hx-confirm="Are you sure you want to delete this meal?"
						class="delete-btn">
						Delete
					</button>
				</div>
			</div>
			<div id="meal-{{.ID}}-ingredients" class="meal-ingredients"></div>
		</div>
	`

	data := struct {
		ID          int64
		Name        string
		Description string
		MealType    string
	}{id, name, description, mealType}

	t := template.Must(template.New("meal").Parse(tmpl))
	t.Execute(w, data)
}

// DeleteMealHandler handles deleting a meal
func DeleteMealHandler(w http.ResponseWriter, r *http.Request) {
	userID := auth.GetUserID(r)

	idStr := strings.TrimPrefix(r.URL.Path, "/meals/")
	id, err := strconv.Atoi(idStr)
	if err != nil {
		http.Error(w, "Invalid ID", http.StatusBadRequest)
		return
	}

	if err := database.DeleteMeal(userID, id); err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	w.WriteHeader(http.StatusOK)
}

// GetMealIngredientsHandler shows ingredients for a specific meal
func GetMealIngredientsHandler(w http.ResponseWriter, r *http.Request) {
	userID := auth.GetUserID(r)

	parts := strings.Split(r.URL.Path, "/")
	if len(parts) < 3 {
		http.Error(w, "Invalid URL", http.StatusBadRequest)
		return
	}

	mealID, err := strconv.Atoi(parts[2])
	if err != nil {
		http.Error(w, "Invalid meal ID", http.StatusBadRequest)
		return
	}

	mealIngredients, err := database.GetMealIngredients(userID, mealID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	allIngredients, err := database.GetAllIngredients(userID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	tmpl := `
		<div class="ingredients-section">
			<h4>Ingredients:</h4>

			<form hx-post="/meals/{{.MealID}}/ingredients"
				  hx-target="#meal-{{.MealID}}-ingredients-list"
				  hx-swap="beforeend"
				  class="add-ingredient-form">
				<select name="ingredient_id" required>
					<option value="">Select ingredient</option>
					{{range .AllIngredients}}
					<option value="{{.ID}}">{{.Name}} ({{.Unit}})</option>
					{{end}}
				</select>
				<input type="number" name="quantity" placeholder="Quantity" step="0.01" min="0" required />
				<button type="submit">Add</button>
			</form>

			<div id="meal-{{.MealID}}-ingredients-list" class="sub-items-list">
				{{range .MealIngredients}}
				<div class="sub-item" id="meal-{{.MealID}}-ingredient-{{.IngredientID}}">
					<span>{{.IngredientName}}: {{.Quantity}} {{.Unit}}</span>
					<button
						hx-delete="/meals/{{.MealID}}/ingredients/{{.IngredientID}}"
						hx-target="#meal-{{.MealID}}-ingredient-{{.IngredientID}}"
						hx-swap="outerHTML"
						class="delete-btn small">
						Remove
					</button>
				</div>
				{{end}}
			</div>
		</div>
	`

	data := struct {
		MealID          int
		MealIngredients interface{}
		AllIngredients  interface{}
	}{
		MealID:          mealID,
		MealIngredients: mealIngredients,
		AllIngredients:  allIngredients,
	}

	t := template.Must(template.New("mealIngredients").Parse(tmpl))
	t.Execute(w, data)
}

// AddMealIngredientHandler adds an ingredient to a meal
func AddMealIngredientHandler(w http.ResponseWriter, r *http.Request) {
	userID := auth.GetUserID(r)

	parts := strings.Split(r.URL.Path, "/")
	if len(parts) < 3 {
		http.Error(w, "Invalid URL", http.StatusBadRequest)
		return
	}

	mealID, err := strconv.Atoi(parts[2])
	if err != nil {
		http.Error(w, "Invalid meal ID", http.StatusBadRequest)
		return
	}

	if err := r.ParseForm(); err != nil {
		http.Error(w, err.Error(), http.StatusBadRequest)
		return
	}

	ingredientID, err := strconv.Atoi(r.FormValue("ingredient_id"))
	if err != nil {
		http.Error(w, "Invalid ingredient ID", http.StatusBadRequest)
		return
	}

	quantity, err := strconv.ParseFloat(r.FormValue("quantity"), 64)
	if err != nil {
		http.Error(w, "Invalid quantity", http.StatusBadRequest)
		return
	}

	if err := database.AddMealIngredient(userID, mealID, ingredientID, quantity); err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	// Get the ingredient details to display
	ingredients, err := database.GetMealIngredients(userID, mealID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	// Find the ingredient we just added
	var addedIngredient *interface{}
	for _, ing := range ingredients {
		if ing.IngredientID == ingredientID {
			var temp interface{} = ing
			addedIngredient = &temp
			break
		}
	}

	if addedIngredient == nil {
		http.Error(w, "Could not find added ingredient", http.StatusInternalServerError)
		return
	}

	tmpl := `
		<div class="sub-item" id="meal-{{.MealID}}-ingredient-{{.IngredientID}}">
			<span>{{.IngredientName}}: {{.Quantity}} {{.Unit}}</span>
			<button
				hx-delete="/meals/{{.MealID}}/ingredients/{{.IngredientID}}"
				hx-target="#meal-{{.MealID}}-ingredient-{{.IngredientID}}"
				hx-swap="outerHTML"
				class="delete-btn small">
				Remove
			</button>
		</div>
	`

	t := template.Must(template.New("mealIngredient").Parse(tmpl))
	t.Execute(w, *addedIngredient)
}

// DeleteMealIngredientHandler removes an ingredient from a meal
func DeleteMealIngredientHandler(w http.ResponseWriter, r *http.Request) {
	userID := auth.GetUserID(r)

	parts := strings.Split(r.URL.Path, "/")
	if len(parts) < 5 {
		http.Error(w, "Invalid URL", http.StatusBadRequest)
		return
	}

	mealID, err := strconv.Atoi(parts[2])
	if err != nil {
		http.Error(w, "Invalid meal ID", http.StatusBadRequest)
		return
	}

	ingredientID, err := strconv.Atoi(parts[4])
	if err != nil {
		http.Error(w, "Invalid ingredient ID", http.StatusBadRequest)
		return
	}

	if err := database.DeleteMealIngredient(userID, mealID, ingredientID); err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	w.WriteHeader(http.StatusOK)
}