/**
 * client-assets/js/soil-import.js
 *
 * Lab file import flow for the soil test entry page.
 *
 * Flow:
 *  1. User selects lab + file → "Analyse" button enabled
 *  2. File sent to soilImportController.php (action=parse)
 *  3. Samples returned → shown in confirmation table
 *     - User can edit sample_id (paddock) inline
 *     - User can uncheck individual rows to skip them
 *  4a. "Import All" / "Import Selected" → action=import_bulk → records saved to DB
 *  4b. For single sample: "Fill Form" → action=import_one → pre-fills the form below
 */

(function () {
    'use strict';

    // ── DOM refs ──────────────────────────────────────────────────────────────
    const labSelect    = document.getElementById('lab-select');
    const fileInput    = document.getElementById('lab-file-input');
    const analyseBtn   = document.getElementById('lab-analyse-btn');
    const statusEl     = document.getElementById('import-status');
    const progressEl   = document.getElementById('import-progress');
    const bulkPanel    = document.getElementById('bulk-import-panel');
    const bulkTbody    = document.getElementById('bulk-import-tbody');
    const bulkImportBtn= document.getElementById('bulk-import-btn');
    const bulkAllChk   = document.getElementById('bulk-select-all');

    if (!fileInput || !analyseBtn) return;

    let parsedSamples = [];   // raw from server
    let detectedLab   = '';

    // ── Helpers ───────────────────────────────────────────────────────────────

    function showStatus(msg, type = 'info') {
        if (!statusEl) return;
        statusEl.className = `alert alert-${type} mt-2`;
        statusEl.innerHTML = msg;
        statusEl.hidden    = false;
    }
    function hideStatus() { if (statusEl) statusEl.hidden = true; }

    function setProgress(on, text = 'Processing…') {
        if (!progressEl) return;
        progressEl.hidden = !on;
        const lbl = progressEl.querySelector('.progress-label');
        if (lbl) lbl.textContent = text;
    }

    function buildFormData(extra = {}) {
        const fd = new FormData();
        fd.append('file', fileInput.files[0]);
        fd.append('lab',  labSelect ? labSelect.value : 'auto');
        for (const [k, v] of Object.entries(extra)) fd.append(k, v);
        return fd;
    }

    async function post(fd) {
        const r = await fetch('/controllers/soilImportController.php', { method: 'POST', body: fd });
        if (!r.ok) throw new Error(`Server error ${r.status}`);
        return r.json();
    }

    // ── Enable Analyse button when file chosen ────────────────────────────────

    fileInput.addEventListener('change', () => {
        analyseBtn.disabled = !fileInput.files.length;
        hideStatus();
        if (bulkPanel) bulkPanel.hidden = true;
    });

    // ── Step 1: Analyse ───────────────────────────────────────────────────────

    analyseBtn.addEventListener('click', async () => {
        if (!fileInput.files.length) return;

        analyseBtn.disabled = true;
        setProgress(true, 'Reading file…');
        hideStatus();
        if (bulkPanel) bulkPanel.hidden = true;

        try {
            const data = await post(buildFormData({ action: 'parse' }));

            if (!data.success) {
                showStatus('Parse error: ' + escHtml(data.error), 'danger');
                return;
            }

            parsedSamples = data.samples;
            detectedLab   = data.lab;

            if (labSelect && labSelect.value === 'auto' && detectedLab) {
                // Update the dropdown to reflect auto-detected lab
                for (const opt of labSelect.options) {
                    if (opt.value === detectedLab) { opt.selected = true; break; }
                }
            }

            if (data.count === 1) {
                // Single sample — offer both "fill form" and "bulk import"
                showStatus(
                    `1 sample found (<strong>${escHtml(parsedSamples[0]?.lab_no || 'unknown')}</strong>). ` +
                    `Review below then import.`,
                    'info'
                );
            } else {
                showStatus(
                    `<strong>${data.count}</strong> samples found in this file. ` +
                    `Review paddock IDs below, then import all or select individual rows.`,
                    'info'
                );
            }

            renderBulkTable(data.samples);

        } catch (err) {
            showStatus('Error: ' + escHtml(err.message), 'danger');
        } finally {
            setProgress(false);
            analyseBtn.disabled = false;
        }
    });

    // ── Step 2: Render confirmation table ─────────────────────────────────────

    function renderBulkTable(samples) {
        if (!bulkPanel || !bulkTbody) return;
        bulkTbody.innerHTML = '';

        samples.forEach((s, idx) => {
            const tr = document.createElement('tr');
            tr.dataset.idx = idx;
            tr.innerHTML = `
                <td class="text-center">
                    <input type="checkbox" class="form-check-input row-check" checked>
                </td>
                <td class="text-muted small">${escHtml(s.lab_no)}</td>
                <td>
                    <input type="text"
                           class="form-control form-control-sm paddock-input"
                           value="${escHtml(s.sample_id)}"
                           placeholder="Paddock / sample ID">
                </td>
                <td class="small">${escHtml(s.client)}</td>
                <td class="small">${escHtml(s.crop)}</td>
                <td class="text-center">
                    <button class="btn btn-xs btn-sm btn-outline-secondary fill-form-btn"
                            data-idx="${idx}" type="button" title="Pre-fill the form below with this sample">
                        <i class="fas fa-pen fa-xs"></i>
                    </button>
                </td>`;
            bulkTbody.appendChild(tr);
        });

        // Wire "fill form" buttons
        bulkTbody.querySelectorAll('.fill-form-btn').forEach(btn => {
            btn.addEventListener('click', () => fillForm(parseInt(btn.dataset.idx)));
        });

        bulkPanel.hidden = false;
        bulkPanel.scrollIntoView({ behavior: 'smooth', block: 'nearest' });
    }

    // ── Select-all checkbox ───────────────────────────────────────────────────

    if (bulkAllChk) {
        bulkAllChk.addEventListener('change', () => {
            document.querySelectorAll('.row-check').forEach(cb => {
                cb.checked = bulkAllChk.checked;
            });
        });
    }

    // ── Step 3a: Bulk import ──────────────────────────────────────────────────

    if (bulkImportBtn) {
        bulkImportBtn.addEventListener('click', async () => {
            const clientId = document.querySelector('[name="client_id"]')?.value || '';
            if (!clientId || clientId === 'new') {
                showStatus('Please select a client before importing.', 'warning');
                document.querySelector('[name="client_id"]')?.scrollIntoView({ behavior: 'smooth' });
                return;
            }

            // Collect checked rows with updated paddock IDs
            const toImport = [];
            bulkTbody.querySelectorAll('tr').forEach(tr => {
                const chk = tr.querySelector('.row-check');
                if (!chk?.checked) return;
                const idx       = parseInt(tr.dataset.idx);
                const paddock   = tr.querySelector('.paddock-input')?.value.trim() || '';
                const sample    = { ...parsedSamples[idx] };
                sample.sample_id = paddock || sample.sample_id;
                // Convert parsed display fields to db field names
                toImport.push(rawSampleToDbFields(idx, sample));
            });

            if (!toImport.length) {
                showStatus('No rows selected.', 'warning');
                return;
            }

            setProgress(true, `Importing ${toImport.length} sample${toImport.length !== 1 ? 's' : ''}…`);
            bulkImportBtn.disabled = true;

            try {
                const fd = buildFormData({
                    action:    'import_bulk',
                    client_id: clientId,
                    samples:   JSON.stringify(toImport),
                });
                const data = await post(fd);

                if (!data.success) {
                    showStatus('Import failed: ' + escHtml(data.error), 'danger');
                    return;
                }

                bulkPanel.hidden = true;
                const skipHtml = data.skipped?.length
                    ? `<br><small class="text-warning">Skipped: ${data.skipped.map(escHtml).join(', ')}</small>`
                    : '';
                showStatus(`<i class="fas fa-check-circle me-1"></i>${escHtml(data.message)}${skipHtml}`, 'success');

            } catch (err) {
                showStatus('Error: ' + escHtml(err.message), 'danger');
            } finally {
                setProgress(false);
                bulkImportBtn.disabled = false;
            }
        });
    }

    // ── Step 3b: Fill form with one sample ────────────────────────────────────

    async function fillForm(idx) {
        setProgress(true, 'Mapping fields…');

        try {
            const fd   = buildFormData({ action: 'import_one', sample_idx: idx });
            const data = await post(fd);

            if (!data.success) {
                showStatus('Could not map fields: ' + escHtml(data.error), 'danger');
                return;
            }

            const { filled } = populateForm(data.fields);
            highlightFilled(data.fields);

            const method = data.method === 'csbp' ? 'CSBP direct map' : 'AI-assisted';
            showStatus(
                `<i class="fas fa-check-circle me-1"></i>${filled} fields filled via ${method}. ` +
                `Review highlighted fields before submitting.`,
                'success'
            );
            document.getElementById('SoilcsvForm')?.scrollIntoView({ behavior: 'smooth' });

        } catch (err) {
            showStatus('Error: ' + escHtml(err.message), 'danger');
        } finally {
            setProgress(false);
        }
    }

    // ── Form population helpers ───────────────────────────────────────────────

    function populateForm(fields) {
        let filled = 0;
        for (const [name, value] of Object.entries(fields)) {
            if (value === null || value === undefined || value === '') continue;
            const el = document.getElementById(name) || document.querySelector(`[name="${name}"]`);
            if (!el) continue;
            if (el.tagName === 'SELECT') {
                const val = String(value).toLowerCase();
                for (const opt of el.options) {
                    if (opt.value.toLowerCase() === val || opt.text.toLowerCase() === val) {
                        el.value = opt.value; filled++; break;
                    }
                }
            } else {
                el.value = value;
                el.dispatchEvent(new Event('input', { bubbles: true }));
                filled++;
            }
        }
        return { filled };
    }

    function highlightFilled(fields) {
        // Clear old highlights first
        document.querySelectorAll('.import-filled').forEach(el => {
            el.classList.remove('import-filled', 'border-success', 'bg-success-subtle');
        });
        for (const name of Object.keys(fields)) {
            if (!fields[name]) continue;
            const el = document.getElementById(name) || document.querySelector(`[name="${name}"]`);
            if (el) el.classList.add('import-filled', 'border-success', 'bg-success-subtle');
        }
    }

    // ── Convert display sample → db field names for bulk save ─────────────────
    // The parsed CSBP sample already uses db field names, so this is mostly pass-through.
    // For generic lab samples (raw headers), the server handles mapping via Ollama.

    function rawSampleToDbFields(idx, sample) {
        // sample already has db keys from csbpParse / genericParse
        // just ensure sample_id is updated from the editable paddock field
        return sample;
    }

    // ── Utility ───────────────────────────────────────────────────────────────

    function escHtml(str) {
        const d = document.createElement('div');
        d.textContent = str || '';
        return d.innerHTML;
    }

})();