function showNotification(message, type = 'info', duration = 3000) {
    const notification = document.createElement('div');
    notification.className = `notification ${type}`;
    notification.textContent = message;
    document.body.appendChild(notification);

    setTimeout(() => {
        notification.classList.add('hiding');
        setTimeout(() => {
            document.body.removeChild(notification);
        }, 300);
    }, duration);
}

function handleFormSubmit(form, button) {
    if (button) {
        button.disabled = true;
        button.classList.add('loading');
    }

    const submitButtons = form.querySelectorAll('input[type="submit"], button[type="submit"]');
    submitButtons.forEach(btn => {
        btn.disabled = true;
        btn.classList.add('loading');
    });
}

function removeLoadingState(form) {
    const submitButtons = form.querySelectorAll('input[type="submit"], button[type="submit"]');
    submitButtons.forEach(btn => {
        btn.disabled = false;
        btn.classList.remove('loading');
    });
}

function enableEnterToSubmit(input, form) {
    input.addEventListener('keydown', (e) => {
        if (e.key === 'Enter' && !e.shiftKey) {
            e.preventDefault();
            form.requestSubmit();
        }
    });
}

function autoResizeTextarea(textarea) {
    textarea.style.height = 'auto';
    textarea.style.height = textarea.scrollHeight + 'px';
}

function addCharacterCounter(textarea, maxLength) {
    const counter = document.createElement('div');
    counter.className = 'char-counter';
    textarea.parentNode.insertBefore(counter, textarea.nextSibling);

    const updateCounter = () => {
        const length = textarea.value.length;
        counter.textContent = `${length}/${maxLength}`;
        if (length > maxLength * 0.9) {
            counter.classList.add('warning');
        } else {
            counter.classList.remove('warning');
        }
    };

    textarea.addEventListener('input', updateCounter);
    updateCounter();
}

function initFormHandling() {
    document.querySelectorAll('form').forEach(form => {
        form.addEventListener('submit', () => {
            const submitButton = form.querySelector('input[type="submit"], button[type="submit"]');
            handleFormSubmit(form, submitButton);
        });
    });

    document.querySelectorAll('textarea').forEach(textarea => {
        textarea.addEventListener('input', () => autoResizeTextarea(textarea));

        if (textarea.id === 'content' || textarea.name === 'content') {
            addCharacterCounter(textarea, 10000);
        }
        if (textarea.id === 'bio' || textarea.name === 'bio') {
            addCharacterCounter(textarea, 500);
        }
    });

    const loginForm = document.querySelector('form[action*="login"]');
    if (loginForm) {
        const passwordInput = loginForm.querySelector('input[type="password"]');
        if (passwordInput) {
            enableEnterToSubmit(passwordInput, loginForm);
        }
    }

    const loginUsername = document.querySelector('input[name="username"]');
    const loginPassword = document.querySelector('input[name="password"]');

    if (loginUsername && loginPassword) {
        loginUsername.addEventListener('blur', () => {
            const error = validateRequired(loginUsername.value, 'Username');
            if (error) {
                showFieldError(loginUsername, error);
            } else {
                clearFieldError(loginUsername);
            }
        });

        loginPassword.addEventListener('blur', () => {
            const error = validateRequired(loginPassword.value, 'Password');
            if (error) {
                showFieldError(loginPassword, error);
            } else {
                clearFieldError(loginPassword);
            }
        });
    }

    const signupForm = document.querySelector('form[action*="signup"]');
    if (signupForm) {
        const usernameInput = signupForm.querySelector('input[name="username"]');
        const passwordInput = signupForm.querySelector('input[name="password"]');
        const confirmInput = signupForm.querySelector('input[name="password_confirm"]');

        if (usernameInput) {
            usernameInput.addEventListener('blur', () => {
                const error = validateUsername(usernameInput.value);
                if (error) {
                    showFieldError(usernameInput, error);
                } else {
                    clearFieldError(usernameInput);
                }
            });
        }

        if (passwordInput) {
            passwordInput.addEventListener('blur', () => {
                const error = validatePassword(passwordInput.value);
                if (error) {
                    showFieldError(passwordInput, error);
                } else {
                    clearFieldError(passwordInput);
                }
            });
        }

        if (confirmInput && passwordInput) {
            confirmInput.addEventListener('blur', () => {
                if (confirmInput.value !== passwordInput.value) {
                    showFieldError(confirmInput, 'Passwords do not match');
                } else {
                    clearFieldError(confirmInput);
                }
            });
        }

        signupForm.addEventListener('submit', (e) => {
            let hasError = false;

            if (usernameInput) {
                const error = validateUsername(usernameInput.value);
                if (error) {
                    showFieldError(usernameInput, error);
                    hasError = true;
                }
            }

            if (passwordInput) {
                const error = validatePassword(passwordInput.value);
                if (error) {
                    showFieldError(passwordInput, error);
                    hasError = true;
                }
            }

            if (confirmInput && passwordInput && confirmInput.value !== passwordInput.value) {
                showFieldError(confirmInput, 'Passwords do not match');
                hasError = true;
            }

            if (hasError) {
                e.preventDefault();
                removeLoadingState(signupForm);
                showNotification('Please fix the errors before submitting', 'error');
            }
        });
    }

    document.querySelectorAll('input[name="title"]').forEach(input => {
        input.addEventListener('blur', () => {
            const error = validateRequired(input.value, 'Title');
            if (error) {
                showFieldError(input, error);
            } else if (input.value.length > 255) {
                showFieldError(input, 'Title is too long (max 255 characters)');
            } else {
                clearFieldError(input);
            }
        });
    });

    document.querySelectorAll('textarea[name="content"]').forEach(textarea => {
        textarea.addEventListener('blur', () => {
            const error = validateRequired(textarea.value, 'Content');
            if (error) {
                showFieldError(textarea, error);
            } else {
                clearFieldError(textarea);
            }
        });
    });
}