document.addEventListener('DOMContentLoaded', () => {
    console.log('DOM fully loaded and parsed');

    const startRecordBtn = document.getElementById('startRecordBtn');
    const stopRecordBtn = document.getElementById('stopRecordBtn');
    const saveRecordBtn = document.getElementById('saveRecordBtn');
    const waveformCanvas = document.getElementById('waveform');
    const recordingsList = document.getElementById('recordingsList');
    const canvasCtx = waveformCanvas.getContext('2d');

    let mediaRecorder;
    let audioChunks = [];
    let audioContext;
    let analyser;
    let source;
    let animationFrameId;
    let streamReference; // Keep a reference to the stream

    async function loadRecordings() {
        console.log('Loading recordings...');
        try {
            const response = await fetch('list_recordings.php');
            const recordings = await response.json();
            console.log('Recordings found:', recordings);
            recordingsList.innerHTML = '';
            if (recordings.length > 0) {
                const list = document.createElement('div');
                list.className = 'list-group';
                recordings.forEach(recording => {
                    const fileName = recording.split('/').pop();
                    const card = document.createElement('div');
                    card.className = 'list-group-item list-group-item-action d-flex justify-content-between align-items-center';

                    const nameSpan = document.createElement('span');
                    nameSpan.className = 'recording-name';
                    nameSpan.textContent = fileName;

                    const playBtn = document.createElement('button');
                    playBtn.className = 'btn btn-play btn-sm rounded-pill';
                    playBtn.innerHTML = '<i class="bi bi-play-fill"></i>';
                    playBtn.onclick = () => {
                        const audio = new Audio(recording);
                        audio.play();
                    };

                    card.appendChild(nameSpan);
                    card.appendChild(playBtn);
                    list.appendChild(card);
                });
                recordingsList.appendChild(list);
            } else {
                recordingsList.innerHTML = '<div class="text-center text-muted p-4"><p>No recordings yet.</p><small>Your saved recordings will appear here.</small></div>';
            }
        } catch (error) {
            console.error('Failed to load recordings:', error);
            recordingsList.innerHTML = '<p class="text-center text-danger">Could not load recordings.</p>';
        }
    }

    startRecordBtn.addEventListener('click', async () => {
        console.log('Start recording button clicked');
        try {
            const stream = await navigator.mediaDevices.getUserMedia({ audio: true });
            streamReference = stream; // Save stream reference
            console.log('Microphone access granted');
            startRecordBtn.disabled = true;
            stopRecordBtn.disabled = false;
            saveRecordBtn.style.display = 'none';
            console.log('UI updated for recording start');

            audioContext = new (window.AudioContext || window.webkitAudioContext)();
            analyser = audioContext.createAnalyser();
            source = audioContext.createMediaStreamSource(stream);
            source.connect(analyser);

            analyser.fftSize = 2048;
            const bufferLength = analyser.frequencyBinCount;
            const dataArray = new Uint8Array(bufferLength);

            const draw = () => {
                animationFrameId = requestAnimationFrame(draw);
                analyser.getByteTimeDomainData(dataArray);
                canvasCtx.fillStyle = '#e9ecef'; // Match the light background
                canvasCtx.fillRect(0, 0, waveformCanvas.width, waveformCanvas.height);
                canvasCtx.lineWidth = 2;
                canvasCtx.strokeStyle = '#0d6efd'; // Primary button color
                canvasCtx.beginPath();
                const sliceWidth = waveformCanvas.width * 1.0 / bufferLength;
                let x = 0;
                for (let i = 0; i < bufferLength; i++) {
                    const v = dataArray[i] / 128.0;
                    const y = v * waveformCanvas.height / 2;
                    if (i === 0) {
                        canvasCtx.moveTo(x, y);
                    } else {
                        canvasCtx.lineTo(x, y);
                    }
                    x += sliceWidth;
                }
                canvasCtx.lineTo(waveformCanvas.width, waveformCanvas.height / 2);
                canvasCtx.stroke();
            };

            draw();
            console.log('Waveform drawing started');

            audioChunks = [];
            mediaRecorder = new MediaRecorder(stream);
            mediaRecorder.ondataavailable = event => {
                console.log('Audio data available, chunk size:', event.data.size);
                audioChunks.push(event.data);
            };
            
            mediaRecorder.onstop = () => {
                console.log('MediaRecorder stopped and onstop event fired.');
                if (streamReference) {
                    streamReference.getTracks().forEach(track => track.stop());
                    console.log('Microphone stream tracks stopped.');
                }
                
                startRecordBtn.disabled = false;
                stopRecordBtn.disabled = true;
                saveRecordBtn.style.display = 'inline-block';
                console.log('Save button is now visible');
                
                cancelAnimationFrame(animationFrameId);
                
                if (audioContext && audioContext.state !== 'closed') {
                    audioContext.close().then(() => console.log('AudioContext closed'));
                }
            };

            mediaRecorder.start();
            console.log('MediaRecorder started');
        } catch (err) {
            console.error('Error starting recording:', err);
            alert('Could not start recording. Please ensure you have a microphone and have granted permission.');
            startRecordBtn.disabled = false;
            stopRecordBtn.disabled = true;
        }
    });

    stopRecordBtn.addEventListener('click', () => {
        console.log('Stop recording button clicked');
        if (mediaRecorder && mediaRecorder.state === 'recording') {
            mediaRecorder.stop();
        } else {
            console.warn('Stop button clicked but mediaRecorder is not recording.');
        }
    });

    saveRecordBtn.addEventListener('click', () => {
        console.log('Save recording button clicked');
        if (audioChunks.length === 0) {
            console.error('No audio chunks to save.');
            alert('There is no audio to save.');
            return;
        }
        const audioBlob = new Blob(audioChunks, { type: 'audio/wav' });
        const formData = new FormData();
        formData.append('audio_data', audioBlob, 'recording.wav');
        console.log('Sending audio data to server. Blob size:', audioBlob.size);

        fetch('save_audio.php', {
            method: 'POST',
            body: formData
        })
        .then(response => {
            console.log('Received response from save_audio.php');
            if (!response.ok) {
                throw new Error(`Server responded with ${response.status}`);
            }
            return response.json();
        })
        .then(data => {
            console.log('Server response:', data);
            if (data.success) {
                alert('Recording saved!');
                saveRecordBtn.style.display = 'none';
                loadRecordings();
            } else {
                const errorMessage = data.error || 'An unknown error occurred.';
                alert('Error saving recording: ' + errorMessage);
                console.error('Server-side save error:', errorMessage);
            }
        })
        .catch(error => {
            console.error('Error saving recording:', error);
            alert('An error occurred while saving the recording. Check the console for details.');
        });
    });

    loadRecordings();
});