// Content insertion management: upload flow, placement form, duration detection.
(function() {
    'use strict';

    // Namespace
    window.MNW = window.MNW || {};

    function startUpload() {
        document.getElementById('insertion-file-input').click();
    }

    async function handleFileSelected(input) {
        const file = input.files[0];
        if (!file) return;

        // Detect duration via temporary audio element
        var durationMs;
        try {
            durationMs = await detectDuration(file);
        } catch (e) {
            showToast('Could not detect audio duration. Please try a different file.');
            input.value = '';
            return;
        }

        try {
            // Step 1: Get presigned URL
            var presignRes = await fetch('/api/users/me/insertions/presign', {
                method: 'POST',
                headers: Object.assign({ 'Content-Type': 'application/json' }, csrfHeaders()),
                body: JSON.stringify({
                    file_name: file.name,
                    content_type: file.type || 'audio/mpeg'
                })
            });

            if (!presignRes.ok) {
                var err = await presignRes.json().catch(function() { return {}; });
                throw new Error(err.error || 'Failed to get upload URL');
            }

            var presignData = await presignRes.json();

            // Step 2: Upload to S3
            var uploadRes = await fetch(presignData.upload_url, {
                method: 'PUT',
                headers: { 'Content-Type': file.type || 'audio/mpeg' },
                body: file
            });

            if (!uploadRes.ok) {
                throw new Error('Upload failed');
            }

            // Step 3: Confirm upload
            var title = file.name.replace(/\.[^.]+$/, '');
            var confirmRes = await fetch('/api/users/me/insertions/confirm', {
                method: 'POST',
                headers: Object.assign({ 'Content-Type': 'application/json' }, csrfHeaders()),
                body: JSON.stringify({
                    s3_key: presignData.s3_key,
                    title: title,
                    duration_ms: durationMs,
                    file_size: file.size,
                    mime_type: file.type || 'audio/mpeg'
                })
            });

            if (!confirmRes.ok) {
                var confirmErr = await confirmRes.json().catch(function() { return {}; });
                throw new Error(confirmErr.error || 'Failed to confirm upload');
            }

            // Refresh the insertion list via HTMX
            htmx.ajax('GET', '/api/users/me/insertions', { target: '#insertion-library', swap: 'outerHTML' });
        } catch (e) {
            showToast('Upload error: ' + e.message);
        }

        input.value = '';
    }

    function detectDuration(file) {
        return new Promise(function(resolve, reject) {
            var audio = document.createElement('audio');
            audio.preload = 'metadata';

            audio.addEventListener('loadedmetadata', function() {
                var ms = Math.round(audio.duration * 1000);
                URL.revokeObjectURL(audio.src);
                resolve(ms);
            });

            audio.addEventListener('error', function() {
                URL.revokeObjectURL(audio.src);
                reject(new Error('Cannot read audio metadata'));
            });

            audio.src = URL.createObjectURL(file);
        });
    }

    function rename(id, currentTitle) {
        var newTitle = prompt('New title:', currentTitle);
        if (!newTitle || newTitle === currentTitle) return;

        fetch('/api/insertions/' + id, {
            method: 'PUT',
            headers: Object.assign({ 'Content-Type': 'application/json' }, csrfHeaders()),
            body: JSON.stringify({ title: newTitle })
        }).then(function() {
            htmx.ajax('GET', '/api/users/me/insertions', { target: '#insertion-library', swap: 'outerHTML' });
        });
    }

    function toggleOffsetInput(position) {
        var group = document.getElementById('offset-input-group');
        if (group) {
            group.classList.toggle('hidden', position !== 'mid_roll');
        }
    }

    function addPlacement(itemId) {
        var insertionId = document.getElementById('placement-insertion-id').value;
        var position = document.getElementById('placement-position').value;
        var offsetInput = document.getElementById('placement-offset');
        var offsetMs = null;

        if (position === 'mid_roll') {
            var offsetSecs = parseInt(offsetInput.value, 10);
            if (isNaN(offsetSecs) || offsetSecs < 0) {
                showToast('Please enter a valid offset in seconds for mid-roll.');
                return;
            }
            offsetMs = offsetSecs * 1000;
        }

        fetch('/api/items/' + itemId + '/insertions', {
            method: 'POST',
            headers: Object.assign({ 'Content-Type': 'application/json' }, csrfHeaders()),
            body: JSON.stringify({
                insertion_id: insertionId,
                position: position,
                offset_ms: offsetMs,
                sort_order: 0
            })
        }).then(function(res) {
            if (res.ok) {
                htmx.ajax('GET', '/api/items/' + itemId + '/insertions', { target: '#placement-list', swap: 'outerHTML' });
            } else {
                res.json().then(function(data) {
                    showToast(data.error || 'Failed to add clip');
                }).catch(function() {
                    showToast('Failed to add clip');
                });
            }
        });
    }

    MNW.insertions = {
        startUpload: startUpload,
        handleFileSelected: handleFileSelected,
        rename: rename,
        toggleOffsetInput: toggleOffsetInput,
        addPlacement: addPlacement
    };
})();