(function () {
    function formatSub(item) {
        return '同花顺 ' + item.ths_code +
            (item.market_code ? ' · ' + item.market_code : '') +
            ' · ' + (item.exchange || '');
    }

    function formatInputLabel(item) {
        return item.input_label || (item.name + ' ' + item.ths_code);
    }

    function itemMatchesQuery(item, qLower) {
        if (!qLower) return true;
        var hay = (
            item.name + ' ' + item.ths_code + ' ' +
            (item.display || '') + ' ' + (item.contract || '') + ' ' +
            (item.exchange || '')
        ).toLowerCase();
        return hay.indexOf(qLower) >= 0;
    }

    function initSymbolInput(wrapper) {
        const input = wrapper.querySelector('.symbol-input');
        const hiddenThs = wrapper.querySelector('input[name="symbol"]');
        const hiddenName = wrapper.querySelector('input[name="symbol_name"]');
        const hiddenMarket = wrapper.querySelector('input[name="market_code"]');
        const hiddenSina = wrapper.querySelector('input[name="sina_code"]');
        const dropdown = wrapper.querySelector('.symbol-dropdown');
        const selectedEl = wrapper.querySelector('.symbol-selected');
        const isMarketPicker = wrapper.classList.contains('market-symbol-wrap');
        let timer = null;
        let abortCtrl = null;
        const cache = new Map();
        let mainsCache = null;
        let mainsLoading = false;

        function hideDropdown() {
            dropdown.classList.remove('show');
        }

        function selectItem(item) {
            const label = formatInputLabel(item);
            input.value = label;
            hiddenThs.value = item.ths_code;
            hiddenName.value = item.name;
            if (hiddenMarket) hiddenMarket.value = item.market_code || '';
            if (hiddenSina) hiddenSina.value = item.sina_code || '';
            selectedEl.textContent = formatSub(item);
            hideDropdown();
            if (isMarketPicker) {
                input.dispatchEvent(new CustomEvent('symbol-selected', { detail: item }));
            }
        }

        function buildOptionEl(item) {
            const div = document.createElement('div');
            div.className = 'symbol-option';
            if (item.near_expiry) {
                div.classList.add('near-expiry');
            }
            var label = item.display || (item.name + ' ' + item.ths_code);
            if (item.near_expiry) {
                label += ' <span class="near-expiry-tag">临期</span>';
            }
            div.innerHTML = label +
                '<div class="sub">' + formatSub(item) + '</div>';
            div.addEventListener('mousedown', function (e) {
                e.preventDefault();
                selectItem(item);
            });
            return div;
        }

        function renderItems(items) {
            dropdown.innerHTML = '';
            if (!items.length) {
                dropdown.innerHTML = '<div class="symbol-option">无匹配，可输入同花顺代码如 ag2608</div>';
            } else {
                items.forEach(function (item) {
                    dropdown.appendChild(buildOptionEl(item));
                });
            }
            dropdown.classList.add('show');
        }

        function renderGrouped(groups, filterQ) {
            dropdown.innerHTML = '';
            const qLower = (filterQ || '').trim().toLowerCase();
            let any = false;
            groups.forEach(function (group) {
                const items = group.items.filter(function (item) {
                    return itemMatchesQuery(item, qLower);
                });
                if (!items.length) return;
                any = true;
                const head = document.createElement('div');
                head.className = 'symbol-group-head';
                head.textContent = group.category;
                dropdown.appendChild(head);
                items.forEach(function (item) {
                    dropdown.appendChild(buildOptionEl(item));
                });
            });
            if (!any) {
                dropdown.innerHTML = '<div class="symbol-option">无匹配品种，可输入合约代码如 ag2608</div>';
            }
            dropdown.classList.add('show');
        }

        function showMarketMains(filterQ) {
            if (mainsCache) {
                renderGrouped(mainsCache, filterQ);
                return;
            }
            if (mainsLoading) {
                dropdown.innerHTML = '<div class="symbol-option">正在识别主力合约…</div>';
                dropdown.classList.add('show');
                return;
            }
            mainsLoading = true;
            dropdown.innerHTML = '<div class="symbol-option">正在识别主力合约…</div>';
            dropdown.classList.add('show');
            fetch('/api/symbols/mains')
                .then(function (r) { return r.json(); })
                .then(function (groups) {
                    mainsCache = groups;
                    renderGrouped(groups, filterQ);
                })
                .catch(function () {
                    hideDropdown();
                })
                .finally(function () {
                    mainsLoading = false;
                });
        }

        function search(q) {
            if (cache.has(q)) {
                renderItems(cache.get(q));
                return;
            }
            if (abortCtrl) {
                abortCtrl.abort();
            }
            abortCtrl = new AbortController();
            fetch('/api/symbols/search?q=' + encodeURIComponent(q), {
                signal: abortCtrl.signal,
            })
                .then(function (r) { return r.json(); })
                .then(function (items) {
                    cache.set(q, items);
                    renderItems(items);
                })
                .catch(function (err) {
                    if (err && err.name === 'AbortError') return;
                    hideDropdown();
                });
        }

        input.addEventListener('input', function () {
            hiddenThs.value = '';
            hiddenName.value = '';
            if (hiddenMarket) hiddenMarket.value = '';
            if (hiddenSina) hiddenSina.value = '';
            selectedEl.textContent = '';
            const q = input.value.trim();
            if (!q) {
                if (isMarketPicker) {
                    showMarketMains('');
                } else {
                    hideDropdown();
                }
                return;
            }
            clearTimeout(timer);
            timer = setTimeout(function () {
                if (isMarketPicker) {
                    showMarketMains(q);
                } else {
                    search(q);
                }
            }, 120);
        });

        input.addEventListener('blur', function () {
            setTimeout(hideDropdown, 150);
        });

        input.addEventListener('focus', function () {
            const q = input.value.trim();
            if (isMarketPicker) {
                showMarketMains(q);
                return;
            }
            if (q && !hiddenThs.value) {
                search(q);
            }
        });
    }

    document.addEventListener('DOMContentLoaded', function () {
        document.querySelectorAll('.symbol-wrap').forEach(initSymbolInput);

        document.querySelectorAll('form').forEach(function (form) {
            if (!form.querySelector('.symbol-wrap')) return;
            if (form.id === 'market-form') return;
            form.addEventListener('submit', function (e) {
                const ths = form.querySelector('input[name="symbol"]');
                const market = form.querySelector('input[name="market_code"]');
                if (ths && !ths.value.trim()) {
                    e.preventDefault();
                    alert('请从下拉列表选择品种');
                    return;
                }
                if (market && !market.value.trim()) {
                    e.preventDefault();
                    alert('请从下拉列表选择品种（需含同花顺行情代码）');
                }
            });
        });
    });
})();