import { qs, clone, set_text } from './lib/dom.mjs';
import * as api from './lib/api.mjs';

// ---------------------------------------------------------------------------
// State
// ---------------------------------------------------------------------------

let section = 'components';
let all_components = [];
let all_fields = [];
let all_inventory = [];
let component_search = '';
let inventory_search = '';
let inventory_type_filter = '';

// ---------------------------------------------------------------------------
// Data loading
// ---------------------------------------------------------------------------

async function load_all() {
	const [cf, ci, cmp] = await Promise.all([
		api.get_fields(),
		api.get_inventory(),
		api.get_components(),
	]);
	all_fields = cf.fields;
	all_inventory = ci.entries;
	all_components = cmp.components;
}

// ---------------------------------------------------------------------------
// Helpers
// ---------------------------------------------------------------------------

const LOCATION_TYPE_LABEL = { physical: 'Physical', bom: 'BOM', digital: 'Digital' };
const LOCATION_TYPE_ICON  = { physical: '📦', bom: '📋', digital: '💡' };

function ref_label_for_type(type) {
	if (type === 'physical') return 'Location (drawer, bin, shelf…)';
	if (type === 'bom') return 'Document / project name';
	return 'Note / description';
}

function inventory_for_component(component_id) {
	return all_inventory.filter(e => e.component_id === component_id);
}

function component_by_id(id) {
	return all_components.find(c => c.id === id);
}

function field_by_id(id) {
	return all_fields.find(f => f.id === id);
}

function matches_search(component, query) {
	if (!query) return true;
	const q = query.toLowerCase();
	if (component.name.toLowerCase().includes(q)) return true;
	if (component.description.toLowerCase().includes(q)) return true;
	for (const val of Object.values(component.fields ?? {})) {
		if (String(val).toLowerCase().includes(q)) return true;
	}
	// Also search inventory locations for this component
	for (const entry of inventory_for_component(component.id)) {
		if (entry.location_ref.toLowerCase().includes(q)) return true;
	}
	return false;
}

function matches_inventory_search(entry, query, type_filter) {
	if (type_filter && entry.location_type !== type_filter) return false;
	if (!query) return true;
	const q = query.toLowerCase();
	const comp = component_by_id(entry.component_id);
	if (comp && comp.name.toLowerCase().includes(q)) return true;
	if (entry.location_ref.toLowerCase().includes(q)) return true;
	if (entry.notes.toLowerCase().includes(q)) return true;
	return false;
}

// ---------------------------------------------------------------------------
// Render: Components section
// ---------------------------------------------------------------------------

function render_components() {
	const main = document.getElementById('main');
	let section_el = document.getElementById('section-components');
	if (!section_el) {
		const frag = document.getElementById('t-section-components').content.cloneNode(true);
		main.replaceChildren(frag);
		section_el = document.getElementById('section-components');

		qs(section_el, '#component-search').addEventListener('input', (e) => {
			component_search = e.target.value;
			render_component_list();
		});
		qs(section_el, '#btn-add-component').addEventListener('click', () => open_component_dialog());
	}

	qs(section_el, '#component-search').value = component_search;
	render_component_list();
}

function render_component_list() {
	const list_el = document.getElementById('component-list');
	const query = component_search.trim();
	const visible = all_components.filter(c => matches_search(c, query));

	if (visible.length === 0) {
		const empty = document.createElement('div');
		empty.className = 'empty-state';
		empty.textContent = query ? 'No components match your search.' : 'No components yet. Add one!';
		list_el.replaceChildren(empty);
		return;
	}

	list_el.replaceChildren(...visible.map(build_component_row));
}

function build_component_row(comp) {
	const row = clone('t-component-row');
	set_text(row, '.component-name', comp.name);
	set_text(row, '.component-description', comp.description || '');

	// Field tags
	const fields_el = qs(row, '.component-fields');
	const field_entries = Object.entries(comp.fields ?? {});
	if (field_entries.length > 0) {
		fields_el.replaceChildren(...field_entries.map(([fid, val]) => {
			const tag = clone('t-field-tag');
			const def = field_by_id(fid);
			const label = def ? def.name : fid;
			const display_val = def?.unit ? `${val} ${def.unit}` : String(val);
			set_text(tag, '.tag-name', label);
			set_text(tag, '.tag-value', display_val);
			return tag;
		}));
	}

	// Location badges
	const locs_el = qs(row, '.component-locations');
	const entries = inventory_for_component(comp.id);
	if (entries.length > 0) {
		locs_el.replaceChildren(...entries.map(entry => {
			const badge = clone('t-location-badge');
			badge.classList.add(`type-${entry.location_type}`);
			set_text(badge, '.badge-icon', LOCATION_TYPE_ICON[entry.location_type] ?? '');
			const ref_text = entry.location_ref || LOCATION_TYPE_LABEL[entry.location_type];
			const qty_text = entry.quantity ? ` ×${entry.quantity}` : '';
			set_text(badge, '.badge-text', ref_text + qty_text);
			return badge;
		}));
	}

	qs(row, '.btn-edit').addEventListener('click', () => open_component_dialog(comp));
	qs(row, '.btn-delete').addEventListener('click', () => confirm_delete(
		`Delete component "${comp.name}"? Inventory entries for it will remain but become orphaned.`,
		async () => {
			await api.delete_component(comp.id);
			all_components = all_components.filter(c => c.id !== comp.id);
			render_component_list();
		}
	));

	return row;
}

// ---------------------------------------------------------------------------
// Render: Inventory section
// ---------------------------------------------------------------------------

function render_inventory() {
	const main = document.getElementById('main');
	let section_el = document.getElementById('section-inventory');
	if (!section_el) {
		const frag = document.getElementById('t-section-inventory').content.cloneNode(true);
		main.replaceChildren(frag);
		section_el = document.getElementById('section-inventory');

		qs(section_el, '#inventory-search').addEventListener('input', (e) => {
			inventory_search = e.target.value;
			render_inventory_list();
		});
		qs(section_el, '#inventory-type-filter').addEventListener('change', (e) => {
			inventory_type_filter = e.target.value;
			render_inventory_list();
		});
		qs(section_el, '#btn-add-inventory').addEventListener('click', () => open_inventory_dialog());
	}

	qs(section_el, '#inventory-search').value = inventory_search;
	qs(section_el, '#inventory-type-filter').value = inventory_type_filter;
	render_inventory_list();
}

function render_inventory_list() {
	const list_el = document.getElementById('inventory-list');
	const visible = all_inventory.filter(e => matches_inventory_search(e, inventory_search.trim(), inventory_type_filter));

	if (visible.length === 0) {
		const empty = document.createElement('div');
		empty.className = 'empty-state';
		empty.textContent = 'No inventory entries match your filter.';
		list_el.replaceChildren(empty);
		return;
	}

	list_el.replaceChildren(...visible.map(build_inventory_row));
}

function build_inventory_row(entry) {
	const row = clone('t-inventory-row');
	const comp = component_by_id(entry.component_id);
	set_text(row, '.inv-component-name', comp ? comp.name : '(deleted component)');

	const pill = document.createElement('span');
	pill.className = `type-pill type-${entry.location_type}`;
	pill.textContent = LOCATION_TYPE_LABEL[entry.location_type] ?? entry.location_type;
	qs(row, '.inv-type-badge').replaceChildren(pill);

	set_text(row, '.inv-location-ref', entry.location_ref);
	set_text(row, '.inv-quantity', entry.quantity);
	set_text(row, '.inv-notes', entry.notes);

	qs(row, '.btn-edit').addEventListener('click', () => open_inventory_dialog(entry));
	qs(row, '.btn-delete').addEventListener('click', () => confirm_delete(
		`Delete this inventory entry (${LOCATION_TYPE_LABEL[entry.location_type]}: ${entry.location_ref || '—'})?`,
		async () => {
			await api.delete_inventory(entry.id);
			all_inventory = all_inventory.filter(e => e.id !== entry.id);
			render_inventory_list();
		}
	));

	return row;
}

// ---------------------------------------------------------------------------
// Render: Fields section
// ---------------------------------------------------------------------------

function render_fields() {
	const main = document.getElementById('main');
	let section_el = document.getElementById('section-fields');
	if (!section_el) {
		const frag = document.getElementById('t-section-fields').content.cloneNode(true);
		main.replaceChildren(frag);
		section_el = document.getElementById('section-fields');
		qs(section_el, '#btn-add-field').addEventListener('click', () => open_field_dialog());
	}
	render_field_list();
}

function render_field_list() {
	const list_el = document.getElementById('field-list');

	if (all_fields.length === 0) {
		const empty = document.createElement('div');
		empty.className = 'empty-state';
		empty.textContent = 'No field definitions yet. Add some!';
		list_el.replaceChildren(empty);
		return;
	}

	list_el.replaceChildren(...all_fields.map(build_field_row));
}

function build_field_row(fdef) {
	const row = clone('t-field-row');
	set_text(row, '.fdef-name', fdef.name);
	set_text(row, '.fdef-unit', fdef.unit || '—');
	set_text(row, '.fdef-description', fdef.description || '');

	qs(row, '.btn-edit').addEventListener('click', () => open_field_dialog(fdef));
	qs(row, '.btn-delete').addEventListener('click', () => confirm_delete(
		`Delete field definition "${fdef.name}"? This will not remove values already stored on components.`,
		async () => {
			await api.delete_field(fdef.id);
			all_fields = all_fields.filter(f => f.id !== fdef.id);
			render_field_list();
		}
	));

	return row;
}

// ---------------------------------------------------------------------------
// Dialog: Component
// ---------------------------------------------------------------------------

let component_dialog_callback = null;

function open_component_dialog(comp = null) {
	const dlg = document.getElementById('dialog-component');
	const title = qs(dlg, '.dialog-title');
	const name_input = qs(dlg, '#c-name');
	const desc_input = qs(dlg, '#c-description');
	const field_rows_el = qs(dlg, '#c-field-rows');
	const add_field_sel = qs(dlg, '#c-add-field-select');

	title.textContent = comp ? `Edit component` : 'Add component';
	name_input.value = comp?.name ?? '';
	desc_input.value = comp?.description ?? '';

	// Build field rows from component's existing values
	const active_fields = new Map(Object.entries(comp?.fields ?? {}));

	function rebuild_field_rows() {
		field_rows_el.replaceChildren(...[...active_fields.entries()].map(([fid, val]) => {
			const def = field_by_id(fid);
			const label_text = def ? def.name : fid;
			const unit_text = def?.unit ? ` [${def.unit}]` : '';

			const row_el = document.createElement('div');
			row_el.className = 'c-field-input-row';

			const label_el = document.createElement('div');
			label_el.className = 'c-field-input-label';
			label_el.textContent = label_text;
			if (unit_text) {
				const unit_span = document.createElement('span');
				unit_span.className = 'c-field-unit-hint';
				unit_span.textContent = unit_text;
				label_el.appendChild(unit_span);
			}

			const input_el = document.createElement('input');
			input_el.type = 'text';
			input_el.className = 'c-field-value';
			input_el.value = val;
			input_el.autocomplete = 'off';
			input_el.dataset.field_id = fid;
			input_el.addEventListener('input', (e) => {
				active_fields.set(fid, e.target.value);
			});

			const remove_btn = document.createElement('button');
			remove_btn.type = 'button';
			remove_btn.className = 'btn-icon btn-danger';
			remove_btn.textContent = '✕';
			remove_btn.title = 'Remove field value';
			remove_btn.addEventListener('click', () => {
				active_fields.delete(fid);
				rebuild_field_rows();
				rebuild_add_select();
			});

			row_el.appendChild(label_el);
			row_el.appendChild(input_el);
			row_el.appendChild(remove_btn);
			return row_el;
		}));
	}

	function rebuild_add_select() {
		const available = all_fields.filter(f => !active_fields.has(f.id));
		add_field_sel.replaceChildren(
			Object.assign(document.createElement('option'), { value: '', textContent: '— add a field —' }),
			...available.map(f => Object.assign(document.createElement('option'), {
				value: f.id,
				textContent: f.name + (f.unit ? ` [${f.unit}]` : ''),
			}))
		);
	}

	rebuild_field_rows();
	rebuild_add_select();

	// Wire add-field select
	const old_handler = add_field_sel._change_handler;
	if (old_handler) add_field_sel.removeEventListener('change', old_handler);
	add_field_sel._change_handler = (e) => {
		const fid = e.target.value;
		if (!fid) return;
		active_fields.set(fid, '');
		rebuild_field_rows();
		rebuild_add_select();
		// Focus the new input
		const inputs = field_rows_el.querySelectorAll(`[data-field_id="${fid}"]`);
		if (inputs.length) inputs[inputs.length - 1].focus();
	};
	add_field_sel.addEventListener('change', add_field_sel._change_handler);

	component_dialog_callback = async () => {
		const name = name_input.value.trim();
		if (!name) return;
		const fields = {};
		for (const [fid, val] of active_fields.entries()) {
			if (val.trim()) fields[fid] = val.trim();
		}
		const body = { name, description: desc_input.value.trim(), fields };
		if (comp) {
			const result = await api.update_component(comp.id, body);
			const idx = all_components.findIndex(c => c.id === comp.id);
			if (idx !== -1) all_components[idx] = result.component;
		} else {
			const result = await api.create_component(body);
			all_components.push(result.component);
			all_components.sort((a, b) => a.name.localeCompare(b.name));
		}
	};

	dlg.showModal();
	name_input.focus();
}

// ---------------------------------------------------------------------------
// Dialog: Inventory entry
// ---------------------------------------------------------------------------

let inventory_dialog_callback = null;

function open_inventory_dialog(entry = null) {
	const dlg = document.getElementById('dialog-inventory');
	const title = qs(dlg, '.dialog-title');
	const comp_sel = qs(dlg, '#i-component');
	const type_sel = qs(dlg, '#i-type');
	const ref_input = qs(dlg, '#i-ref');
	const ref_label = qs(dlg, '#i-ref-label');
	const qty_input = qs(dlg, '#i-qty');
	const notes_input = qs(dlg, '#i-notes');

	title.textContent = entry ? 'Edit inventory entry' : 'Add inventory entry';

	// Populate component dropdown
	comp_sel.replaceChildren(
		Object.assign(document.createElement('option'), { value: '', textContent: '— select component —' }),
		...all_components.map(c => Object.assign(document.createElement('option'), {
			value: c.id,
			textContent: c.name,
		}))
	);
	comp_sel.value = entry?.component_id ?? '';
	type_sel.value = entry?.location_type ?? 'physical';
	ref_input.value = entry?.location_ref ?? '';
	qty_input.value = entry?.quantity ?? '';
	notes_input.value = entry?.notes ?? '';

	function update_ref_label() {
		ref_label.textContent = ref_label_for_type(type_sel.value);
	}
	update_ref_label();

	const old_type_handler = type_sel._change_handler;
	if (old_type_handler) type_sel.removeEventListener('change', old_type_handler);
	type_sel._change_handler = update_ref_label;
	type_sel.addEventListener('change', type_sel._change_handler);

	inventory_dialog_callback = async () => {
		const body = {
			component_id: comp_sel.value,
			location_type: type_sel.value,
			location_ref: ref_input.value.trim(),
			quantity: qty_input.value.trim(),
			notes: notes_input.value.trim(),
		};
		if (entry) {
			const result = await api.update_inventory(entry.id, body);
			const idx = all_inventory.findIndex(e => e.id === entry.id);
			if (idx !== -1) all_inventory[idx] = result.entry;
		} else {
			const result = await api.create_inventory(body);
			all_inventory.push(result.entry);
		}
	};

	dlg.showModal();
	comp_sel.focus();
}

// ---------------------------------------------------------------------------
// Dialog: Field definition
// ---------------------------------------------------------------------------

let field_dialog_callback = null;

function open_field_dialog(fdef = null) {
	const dlg = document.getElementById('dialog-field');
	const title = qs(dlg, '.dialog-title');
	const name_input = qs(dlg, '#f-name');
	const unit_input = qs(dlg, '#f-unit');
	const desc_input = qs(dlg, '#f-description');

	title.textContent = fdef ? 'Edit field' : 'Add field';
	name_input.value = fdef?.name ?? '';
	unit_input.value = fdef?.unit ?? '';
	desc_input.value = fdef?.description ?? '';

	field_dialog_callback = async () => {
		const body = {
			name: name_input.value.trim(),
			unit: unit_input.value.trim(),
			description: desc_input.value.trim(),
		};
		if (fdef) {
			const result = await api.update_field(fdef.id, body);
			const idx = all_fields.findIndex(f => f.id === fdef.id);
			if (idx !== -1) all_fields[idx] = result.field;
			all_fields.sort((a, b) => a.name.localeCompare(b.name));
		} else {
			const result = await api.create_field(body);
			all_fields.push(result.field);
			all_fields.sort((a, b) => a.name.localeCompare(b.name));
		}
	};

	dlg.showModal();
	name_input.focus();
}

// ---------------------------------------------------------------------------
// Dialog: Confirm delete
// ---------------------------------------------------------------------------

let confirm_callback = null;

function confirm_delete(message, on_confirm) {
	const dlg = document.getElementById('dialog-confirm');
	document.getElementById('confirm-message').textContent = message;
	confirm_callback = on_confirm;
	dlg.showModal();
}

// ---------------------------------------------------------------------------
// Render dispatcher
// ---------------------------------------------------------------------------

function render() {
	if (section === 'components') render_components();
	else if (section === 'inventory') render_inventory();
	else if (section === 'fields') render_fields();
}

// ---------------------------------------------------------------------------
// Init
// ---------------------------------------------------------------------------

async function init() {
	// Load templates
	const html = await fetch('/templates.html').then(r => r.text());
	document.body.insertAdjacentHTML('beforeend', html);

	// Clone and mount dialogs
	for (const id of ['t-dialog-component', 't-dialog-inventory', 't-dialog-field', 't-dialog-confirm']) {
		const frag = document.getElementById(id).content.cloneNode(true);
		document.body.appendChild(frag);
	}

	// Wire dialog form submissions
	document.getElementById('form-component').addEventListener('submit', async (e) => {
		e.preventDefault();
		try {
			await component_dialog_callback?.();
			document.getElementById('dialog-component').close();
			render();
		} catch (err) {
			alert(`Error: ${err.message}`);
		}
	});
	document.getElementById('c-cancel').addEventListener('click', () => {
		document.getElementById('dialog-component').close();
	});

	document.getElementById('form-inventory').addEventListener('submit', async (e) => {
		e.preventDefault();
		try {
			await inventory_dialog_callback?.();
			document.getElementById('dialog-inventory').close();
			render();
		} catch (err) {
			alert(`Error: ${err.message}`);
		}
	});
	document.getElementById('i-cancel').addEventListener('click', () => {
		document.getElementById('dialog-inventory').close();
	});

	document.getElementById('form-field').addEventListener('submit', async (e) => {
		e.preventDefault();
		try {
			await field_dialog_callback?.();
			document.getElementById('dialog-field').close();
			render();
		} catch (err) {
			alert(`Error: ${err.message}`);
		}
	});
	document.getElementById('f-cancel').addEventListener('click', () => {
		document.getElementById('dialog-field').close();
	});

	document.getElementById('confirm-ok').addEventListener('click', async () => {
		try {
			await confirm_callback?.();
			document.getElementById('dialog-confirm').close();
			render();
		} catch (err) {
			alert(`Error: ${err.message}`);
		}
	});
	document.getElementById('confirm-cancel').addEventListener('click', () => {
		document.getElementById('dialog-confirm').close();
	});

	// Nav wiring
	document.querySelectorAll('.nav-btn').forEach(btn => {
		btn.addEventListener('click', () => {
			document.querySelectorAll('.nav-btn').forEach(b => b.classList.remove('active'));
			btn.classList.add('active');
			section = btn.dataset.section;
			render();
		});
	});

	// Load data
	await load_all();
	render();
}

init();