<template>
<div class="vblkjoeq">
	<div class="label" @click="focus"><slot name="label"></slot></div>
	<div class="input" :class="{ inline, disabled, focused }" @click.prevent="onClick" ref="container">
		<div class="prefix" ref="prefixEl"><slot name="prefix"></slot></div>
		<select class="select" ref="inputEl"
			v-model="v"
			:disabled="disabled"
			:required="required"
			:readonly="readonly"
			:placeholder="placeholder"
			@focus="focused = true"
			@blur="focused = false"
			@input="onInput"
		>
			<slot></slot>
		</select>
		<div class="suffix" ref="suffixEl"><i class="fas fa-chevron-down"></i></div>
	</div>
	<div class="caption"><slot name="caption"></slot></div>

	<MkButton v-if="manualSave && changed" @click="updated" primary><i class="fas fa-save"></i> {{ $ts.save }}</MkButton>
</div>
</template>

<script lang="ts">
import { defineComponent, onMounted, onUnmounted, nextTick, ref, watch, computed, toRefs, VNode } from 'vue';
import MkButton from '@client/components/ui/button.vue';
import * as os from '@client/os';

export default defineComponent({
	components: {
		MkButton,
	},

	props: {
		modelValue: {
			required: true
		},
		required: {
			type: Boolean,
			required: false
		},
		readonly: {
			type: Boolean,
			required: false
		},
		disabled: {
			type: Boolean,
			required: false
		},
		placeholder: {
			type: String,
			required: false
		},
		autofocus: {
			type: Boolean,
			required: false,
			default: false
		},
		inline: {
			type: Boolean,
			required: false,
			default: false
		},
		manualSave: {
			type: Boolean,
			required: false,
			default: false
		},
	},

	emits: ['change', 'update:modelValue'],

	setup(props, context) {
		const { modelValue, autofocus } = toRefs(props);
		const v = ref(modelValue.value);
		const focused = ref(false);
		const changed = ref(false);
		const invalid = ref(false);
		const filled = computed(() => v.value !== '' && v.value != null);
		const inputEl = ref(null);
		const prefixEl = ref(null);
		const suffixEl = ref(null);
		const container = ref(null);

		const focus = () => inputEl.value.focus();
		const onInput = (ev) => {
			changed.value = true;
			context.emit('change', ev);
		};

		const updated = () => {
			changed.value = false;
			context.emit('update:modelValue', v.value);
		};

		watch(modelValue, newValue => {
			v.value = newValue;
		});

		watch(v, newValue => {
			if (!props.manualSave) {
				updated();
			}

			invalid.value = inputEl.value.validity.badInput;
		});

		onMounted(() => {
			nextTick(() => {
				if (autofocus.value) {
					focus();
				}

				// このコンポーネントが作成された時、非表示状態である場合がある
				// 非表示状態だと要素の幅などは0になってしまうので、定期的に計算する
				const clock = setInterval(() => {
					if (prefixEl.value) {
						if (prefixEl.value.offsetWidth) {
							inputEl.value.style.paddingLeft = prefixEl.value.offsetWidth + 'px';
						}
					}
					if (suffixEl.value) {
						if (suffixEl.value.offsetWidth) {
							inputEl.value.style.paddingRight = suffixEl.value.offsetWidth + 'px';
						}
					}
				}, 100);

				onUnmounted(() => {
					clearInterval(clock);
				});
			});
		});

		const onClick = (ev: MouseEvent) => {
			focused.value = true;

			const menu = [];
			let options = context.slots.default();

			const pushOption = (option: VNode) => {
				menu.push({
					text: option.children,
					active: v.value === option.props.value,
					action: () => {
						v.value = option.props.value;
					},
				});
			};

			const scanOptions = (options: VNode[]) => {
				for (const vnode of options) {
					if (vnode.type === 'optgroup') {
						const optgroup = vnode;
						menu.push({
							type: 'label',
							text: optgroup.props.label,
						});
						scanOptions(optgroup.children);
					} else if (Array.isArray(vnode.children)) { // 何故かフラグメントになってくることがある
						const fragment = vnode;
						scanOptions(fragment.children);
					} else {
						const option = vnode;
						pushOption(option);
					}
				}
			};

			scanOptions(options);

			os.popupMenu(menu, container.value, {
				width: container.value.offsetWidth,
			}).then(() => {
				focused.value = false;
			});
		};

		return {
			v,
			focused,
			invalid,
			changed,
			filled,
			inputEl,
			prefixEl,
			suffixEl,
			container,
			focus,
			onInput,
			onClick,
			updated,
		};
	},
});
</script>

<style lang="scss" scoped>
.vblkjoeq {
	> .label {
		font-size: 0.85em;
		padding: 0 0 8px 12px;
		user-select: none;

		&:empty {
			display: none;
		}
	}

	> .caption {
		font-size: 0.8em;
		padding: 8px 0 0 12px;
		color: var(--fgTransparentWeak);

		&:empty {
			display: none;
		}
	}

	> .input {
		$height: 42px;
		position: relative;
		cursor: pointer;

		&:hover {
			> .select {
				border-color: var(--inputBorderHover);
			}
		}

		> .select {
			appearance: none;
			-webkit-appearance: none;
			display: block;
			height: $height;
			width: 100%;
			margin: 0;
			padding: 0 12px;
			font: inherit;
			font-weight: normal;
			font-size: 1em;
			color: var(--fg);
			background: var(--panel);
			border: solid 1px var(--inputBorder);
			border-radius: 6px;
			outline: none;
			box-shadow: none;
			box-sizing: border-box;
			cursor: pointer;
			transition: border-color 0.1s ease-out;
			pointer-events: none;
		}

		> .prefix,
		> .suffix {
			display: flex;
			align-items: center;
			position: absolute;
			z-index: 1;
			top: 0;
			padding: 0 12px;
			font-size: 1em;
			height: $height;
			pointer-events: none;

			&:empty {
				display: none;
			}

			> * {
				display: inline-block;
				min-width: 16px;
				max-width: 150px;
				overflow: hidden;
				white-space: nowrap;
				text-overflow: ellipsis;
			}
		}

		> .prefix {
			left: 0;
			padding-right: 6px;
		}

		> .suffix {
			right: 0;
			padding-left: 6px;
		}

		&.inline {
			display: inline-block;
			margin: 0;
		}

		&.focused {
			> select {
				border-color: var(--accent);
			}
		}

		&.disabled {
			opacity: 0.7;

			&, * {
				cursor: not-allowed !important;
			}
		}
	}
}
</style>
