import { Component, NewState, Util, RefreshState } from '@web/state'
import { VirtualScroll } from '@web/base'

Component.register('DataTable', container => {
	const vs = VirtualScroll()
	// 如果 state 还未由框架自动创建，则手动创建
	if (!container.state) container.state = NewState({})
	const state = container.state

	Object.assign(state, {
		list: [], fields: [], renderedList: [],
		prevHeight: 0, postHeight: 0, _listStartIndex: 0,
		selStartR: -1, selStartF: -1, selEndR: -1, selEndF: -1,
		multiSelections: [],
		isSelecting: false
	})

	const refresh = () => {
		const scrollEl = container.querySelector('.dt-body')
		if (!scrollEl) return
		const res = vs.calc(scrollEl, state.list)
		if (res) {
			res.renderedList.forEach((item, i) => {
				if (item && !item.__watch) {
					const wrapped = NewState(item)
					res.renderedList[i] = wrapped
					state.list[res.listStartIndex + i] = wrapped
				}
			})
			Object.assign(state, {
				prevHeight: res.prevHeight, postHeight: res.postHeight,
				_listStartIndex: res.listStartIndex, renderedList: res.renderedList
			})
		}
	}
	container.refresh = refresh

	state.__watch('fields', fields => {
		if (!fields) return
		const leftOffsets = [], rightOffsets = []
		let lSum = 0
		fields.forEach((f, i) => {
			if (f.pinned === 'left') {
				leftOffsets[i] = lSum
				lSum += (f.width || 150)
			}
		})
		fields.forEach((f, i) => {
			if (f.pinned === 'right') {
				let rs = 0
				for (let j = i + 1; j < fields.length; j++) {
					if (fields[j].pinned === 'right') rs += (fields[j].width || 150)
				}
				rightOffsets[i] = rs
			}
		})
		state._leftOffsets = leftOffsets
		state._rightOffsets = rightOffsets
	})

	state.__watch('list', list => {
		state._listStartIndex = 0
		const scrollEl = container.querySelector('.dt-body')
		state.renderedList = vs.reset(list, scrollEl || { clientHeight: 800 }) || []
		if (scrollEl) {
			vs.init(list, refresh)
			requestAnimationFrame(refresh)
		}
	})

	container.onItemUpdate = (rIdx, node) => vs.update(rIdx + state._listStartIndex, node)

	container.getOffset = (index, side) => (state._leftOffsets || [])[index] || (state._rightOffsets || [])[index] || 0

	container.isCellSelected = (r, f) => {
		const rMin = Math.min(state.selStartR, state.selEndR), rMax = Math.max(state.selStartR, state.selEndR)
		const fMin = Math.min(state.selStartF, state.selEndF), fMax = Math.max(state.selStartF, state.selEndF)
		if (r >= rMin && r <= rMax && f >= fMin && f <= fMax) return true
		return state.multiSelections.some(s => r >= s.r1 && r <= s.r2 && f >= s.f1 && f <= s.f2)
	}

	container.clearAllActive = (keepSelection = false) => {
		state.list.forEach(row => { 
			if (row && row.__watch) {
				if (row._editingF !== null) row._editingF = null
				if (row._activeF !== null) row._activeF = null
			}
		})
		if (!keepSelection) {
			state.selStartR = -1; state.multiSelections = []
		}
	}

	container.startSelect = (r, f, e) => {
		const alreadySelected = container.isCellSelected(r, f)
		if (state.editingCell) state.editingCell = null
		
		if (e.shiftKey && state.selStartR !== -1) {
			state.selEndR = r; state.selEndF = f
		} else {
			if (!alreadySelected) {
				if (!e.ctrlKey && !e.metaKey) container.clearAllActive()
				else if (state.selStartR !== -1) {
					state.multiSelections.push({
						r1: Math.min(state.selStartR, state.selEndR), r2: Math.max(state.selStartR, state.selEndR),
						f1: Math.min(state.selStartF, state.selEndF), f2: Math.max(state.selStartF, state.selEndF)
					})
				}
				state.selStartR = state.selEndR = r
				state.selStartF = state.selEndF = f
			}
			state.isSelecting = true
			if (state.list[r] && state.list[r].__watch) state.list[r]._activeF = f
		}
	}

	container.updateSelect = (r, f) => state.isSelecting && (state.selEndR = r, state.selEndF = f)
	container.endSelect = () => state.isSelecting = false

	container.editCell = (row, f, fIdx) => {
		const rMin = Math.min(state.selStartR, state.selEndR), rMax = Math.max(state.selStartR, state.selEndR)
		const fMin = Math.min(state.selStartF, state.selEndF), fMax = Math.max(state.selStartF, state.selEndF)
		const rIdx = state.list.indexOf(row)
		const isInRange = state.selStartR !== -1 && rIdx >= rMin && rIdx <= rMax && fIdx >= fMin && fIdx <= fMax
		
		const count = isInRange ? (rMax - rMin + 1) : 0
		if (count > 1 && globalThis.UI?.toast) {
			UI.toast(`{#Bulk Editing {num} rows... || ${count}#}`)
		}

		container.clearAllActive(true) 
		row._editingF = f.id
		row._activeF = fIdx

		if (count > 1) {
			const unwatch = row.__watch(f.id, (val) => {
				for (let r = rMin; r <= rMax; r++) {
					const cur = state.list[r]
					if (cur !== row) {
						const wrapped = cur.__watch ? cur : NewState(cur)
						state.list[r] = wrapped
						wrapped[f.id] = val
					}
				}
				unwatch()
			})
		}
	}

	const escapeTSV = val => {
		const str = String(val ?? '')
		return (str.includes('\t') || str.includes('\n') || str.includes('"')) ? '"' + str.replace(/"/g, '""') + '"' : str
	}

	const parseTSV = text => {
		const rows = []
		let curRow = [], curCell = '', inQuote = false
		for (let i = 0; i < text.length; i++) {
			const c = text[i], next = text[i+1]
			if (inQuote) {
				if (c === '"' && next === '"') { curCell += '"'; i++ }
				else if (c === '"') inQuote = false
				else curCell += c
			} else {
				if (c === '"') inQuote = true
				else if (c === '\t') { curRow.push(curCell); curCell = '' }
				else if (c === '\n') { curRow.push(curCell); rows.push(curRow); curRow = []; curCell = '' }
				else if (c !== '\r') curCell += c
			}
		}
		curRow.push(curCell); rows.push(curRow)
		return rows
	}

	container.copy = async () => {
		const rMin = Math.min(state.selStartR, state.selEndR), rMax = Math.max(state.selStartR, state.selEndR)
		const fMin = Math.min(state.selStartF, state.selEndF), fMax = Math.max(state.selStartF, state.selEndF)
		if (rMin === -1) return
		const text = state.list.slice(rMin, rMax + 1).map(row => 
			state.fields.slice(fMin, fMax + 1).map(f => escapeTSV(row[f.id])).join('\t')
		).join('\n')
		await navigator.clipboard.writeText(text)
	}

	container.paste = async () => {
		const text = await navigator.clipboard.readText()
		const rows = parseTSV(text)
		const rStart = Math.min(state.selStartR, state.selEndR)
		const fStart = Math.min(state.selStartF, state.selEndF)
		if (rStart === -1) return
		rows.forEach((rowData, i) => {
			let row = state.list[rStart + i]
			if (row) {
				if (!row.__watch) {
					row = NewState(row)
					state.list[rStart + i] = row
				}
				rowData.forEach((val, j) => {
					const field = state.fields[fStart + j]
					if (field) {
						if (typeof row[field.id] === 'boolean') row[field.id] = val.toLowerCase() === 'true'
						else if (typeof row[field.id] === 'number') row[field.id] = Number(val)
						else row[field.id] = val
					}
				})
			}
		})
	}

	container.addEventListener('keydown', e => {
		if (e.ctrlKey || e.metaKey) {
			if (e.key === 'c') { e.preventDefault(); container.copy() }
			if (e.key === 'v') { e.preventDefault(); container.paste() }
		}
	})

	const onGlobalMouseDown = e => !container.contains(e.target) && container.clearAllActive()
	document.addEventListener('mousedown', onGlobalMouseDown)
	window.addEventListener('mouseup', container.endSelect)
	container._onUnload = () => {
		document.removeEventListener('mousedown', onGlobalMouseDown)
		window.removeEventListener('mouseup', container.endSelect)
	}

}, Util.makeDom(/*html*/`
<div class="dt-root d-flex flex-column h-100 border bg-body text-body overflow-hidden" style="position:relative; user-select:none" tabindex="0" onunload="this._onUnload()">
	<div class="dt-header d-flex flex-shrink-0 border-bottom bg-body-tertiary fw-bold text-muted small" style="overflow:hidden; position:sticky; top:0; z-index:20; height:48px">
		<div $each="this.state.fields" as="f" class="dt-col border-end d-flex align-items-center px-2 bg-body-tertiary"
			$style="'width: var(--w-' + f.id + ', ' + (f.width || 150) + 'px); min-width: var(--w-' + f.id + ', ' + (f.width || 150) + 'px); ' + (f.pinned ? 'position:sticky; z-index:11;' : '') + (f.pinned === 'left' ? 'left:' + this.getOffset(index, 'left') + 'px;' : '') + (f.pinned === 'right' ? 'right:' + this.getOffset(index, 'right') + 'px;' : '')">
			<span $text="f.name" $class="'text-truncate flex-grow-1 ' + (f.type === 'number' ? 'text-end' : '')"></span>
			<Resizer class="dt-resizer" $.target="thisNode.parentNode" min="50" max="600" $bind="f.width" $onresizing="thisNode.closest('.dt-root').style.setProperty('--w-' + f.id, event.detail.newSize + 'px')"/>
		</div>
	</div>
	<div class="dt-body flex-grow-1 overflow-auto bg-body" $onscroll="requestAnimationFrame(() => this.refresh())" style="overflow-anchor:none">
		<div $if="this.state.prevHeight>0" $style="'height:' + this.state.prevHeight + 'px;'"></div>
		<div $each="this.state.renderedList" as="row" class="dt-row d-flex border-bottom" $onupdate="this.onItemUpdate(rIdx, thisNode)" index="rIdx">
			<div $each="this.state.fields" as="f" class="dt-cell border-end d-flex align-items-center bg-body"
				$class="'dt-cell border-end d-flex align-items-center bg-body' + (this.isCellSelected(rIdx + this.state._listStartIndex, index) ? ' bg-primary-subtle' : '') + (row._activeF === index ? ' dt-cell-active' : '')"
				$style="'width: var(--w-' + f.id + ', ' + (f.width || 150) + 'px); min-width: var(--w-' + f.id + ', ' + (f.width || 150) + 'px); height:40px; ' + (f.pinned ? 'position:sticky; z-index:10;' : '') + (f.pinned === 'left' ? 'left:' + this.getOffset(index, 'left') + 'px;' : '') + (f.pinned === 'right' ? 'right:' + this.getOffset(index, 'right') + 'px;' : '')"
				$onmousedown="this.startSelect(rIdx + this.state._listStartIndex, index, event)"
				$onmouseenter="this.updateSelect(rIdx + this.state._listStartIndex, index)"
				$ondblclick="this.editCell(row, f, index)">
				
				<div $if="row._editingF !== f.id" $class="'px-2 text-truncate w-100 h-100 d-flex align-items-center ' + (f.type === 'number' ? 'justify-content-end' : (f.type === 'switch' ? 'justify-content-center' : ''))">
					<span $if="typeof row[f.id] !== 'boolean'" $text="row[f.id] ?? ''" class="text-truncate"></span>
					<div $if="typeof row[f.id] === 'boolean'" class="form-switch fs-5 m-0 d-flex align-items-center justify-content-center" style="padding-left:0">
						<input class="form-check-input m-0" type="checkbox" $checked="row[f.id]" disabled>
					</div>
				</div>

				<div $if="row._editingF === f.id" $class="'dt-editor-container' + (f.type === 'textarea' ? ' dt-editor-textarea' : '')" $onclick="event.stopPropagation()" $onmousedown="event.stopPropagation()">
					<AutoForm inline class="dt-editor h-100 w-100" $.state.schema="[{ ...f, name: f.id, label: f.name }]" $.data="row" 
						$onkeydown="(event.key === 'Enter' && f.type !== 'textarea') && (row._editingF = null); event.key === 'Escape' && (row._editingF = null)"/>
				</div>
			</div>
		</div>
		<div $if="this.state.postHeight>0" $style="'height:' + this.state.postHeight + 'px;'"></div>
	</div>
	<style>
		.dt-root { font-size: 0.875rem; --dt-active-border: var(--bs-primary); outline: none; }
		.dt-row:hover .dt-cell { background-color: var(--bs-secondary-bg) !important; }
		.dt-cell { position: relative; transition: background 0.05s; border-color: var(--bs-border-color) !important; }
		.dt-cell.bg-primary-subtle { background-color: var(--bs-primary-bg-subtle) !important; }
		.dt-cell-active::after { content: ''; position: absolute; inset: 0; border: 2px solid var(--dt-active-border); pointer-events: none; z-index: 12; }
		.dt-col { position: relative; }
		.dt-editor-container { position: absolute; left: -1px; top: -1px; width: fit-content; min-width: calc(100% + 2px); height: auto; min-height: calc(100% + 2px); background: var(--bs-body-bg); z-index: 100; box-shadow: 0 4px 12px rgba(0,0,0,.3); border: 1px solid var(--dt-active-border); display: flex; align-items: center; }
		.dt-editor-textarea { height: auto; min-height: 100%; min-width: 260px; align-items: flex-start; }
		.dt-resizer { width: 4px !important; opacity: 0; transition: opacity 0.2s; position: absolute; right: 0; top: 0; height: 100%; background: var(--bs-primary); cursor: col-resize; z-index: 15; }
		.dt-col:hover .dt-resizer { opacity: 0.5; }
		.dt-resizer:hover { opacity: 1 !important; }
	</style>
</div>
`))

if (typeof document !== 'undefined') RefreshState(document.documentElement)