import scanSuccessSoundUrl from "@/assets/sound/scan-success.mp3";
import registrationSuccessSoundUrl from "@/assets/sound/registration-success.mp3";

export interface SoundSetting {
	scanSuccess: boolean;
	registerSuccess: boolean;
	volume: number;
}

type SoundType = "scanSuccess" | "registerSuccess";

const SOUND_STORAGE_KEY = "gao-customer-h5:sound";
const soundUrlMap: Record<SoundType, string> = {
	scanSuccess: scanSuccessSoundUrl,
	registerSuccess: registrationSuccessSoundUrl
};
// Windows 某些设备链路对极短提示音的起音处理不稳定，直接播放会偏小。
// 这里先补一段极低音量的预热头，把输出链路“叫醒”后再接原音效。
const SCAN_SUCCESS_WARMUP_HEAD_MS = 120;
const SCAN_SUCCESS_WARMUP_GAIN = .08;

function createDefaultSoundSetting(): SoundSetting {
	return {
		scanSuccess: true,
		registerSuccess: true,
		volume: 70
	};
}

function readStoredSoundSetting(): SoundSetting {
	const rawValue = localStorage.getItem(SOUND_STORAGE_KEY);
	if (!rawValue) {
		return createDefaultSoundSetting();
	}

	try {
		const parsedValue = JSON.parse(rawValue) as Partial<SoundSetting>;
		const volume = Number(parsedValue.volume);
		return {
			scanSuccess: parsedValue.scanSuccess !== false,
			registerSuccess: parsedValue.registerSuccess !== false,
			volume: Number.isFinite(volume) ? Math.min(100, Math.max(0, volume)) : 70
		};
	} catch {
		return createDefaultSoundSetting();
	}
}

export const useSettingStore = defineStore("setting", () => {
	const sound = ref<SoundSetting>(readStoredSoundSetting());
	const soundPlayerMap = shallowRef<Record<SoundType, HTMLAudioElement> | null>(null);
	const audioContext = shallowRef<AudioContext | null>(null);
	const scanSuccessBuffer = shallowRef<AudioBuffer | null>(null);
	const activeScanSuccessSource = shallowRef<AudioBufferSourceNode | null>(null);
	const soundUnlocked = ref(false);

	function setSound(value: Partial<SoundSetting>): void {
		sound.value = {
			scanSuccess: value.scanSuccess ?? sound.value.scanSuccess,
			registerSuccess: value.registerSuccess ?? sound.value.registerSuccess,
			volume: Math.min(100, Math.max(0, value.volume ?? sound.value.volume))
		};
		localStorage.setItem(SOUND_STORAGE_KEY, JSON.stringify(sound.value));
		applySoundVolume();
	}

	function loadSoundPlayers(): void {
		if (soundPlayerMap.value) {
			return;
		}

		soundPlayerMap.value = {
			scanSuccess: createSoundPlayer(soundUrlMap.scanSuccess),
			registerSuccess: createSoundPlayer(soundUrlMap.registerSuccess)
		};
		applySoundVolume();
	}

	function getAudioContext(): AudioContext {
		if (audioContext.value) {
			return audioContext.value;
		}

		audioContext.value = new window.AudioContext();
		return audioContext.value;
	}

	function createSoundPlayer(url: string): HTMLAudioElement {
		const player = new Audio(url);
		player.preload = "auto";
		player.load();
		return player;
	}

	function applySoundVolume(): void {
		if (!soundPlayerMap.value) {
			return;
		}

		const volume = sound.value.volume / 100;
		Object.values(soundPlayerMap.value).forEach((player) => {
			player.volume = volume;
		});
	}

	async function unlockSoundPlayers(): Promise<boolean> {
		loadSoundPlayers();
		if (soundUnlocked.value || !soundPlayerMap.value) {
			return soundUnlocked.value;
		}

		try {
			await getAudioContext().resume();
			for (const player of Object.values(soundPlayerMap.value)) {
				player.muted = true;
				player.volume = 0;
				player.currentTime = 0;
				await player.play();
				player.pause();
				player.currentTime = 0;
				player.muted = false;
			}
			applySoundVolume();
			soundUnlocked.value = true;
			return true;
		} catch {
			Object.values(soundPlayerMap.value).forEach((player) => {
				player.muted = false;
			});
			applySoundVolume();
			return false;
		}
	}

	async function loadScanSuccessBuffer(): Promise<AudioBuffer> {
		if (scanSuccessBuffer.value) {
			return scanSuccessBuffer.value;
		}

		const response = await fetch(soundUrlMap.scanSuccess);
		const arrayBuffer = await response.arrayBuffer();
		scanSuccessBuffer.value = await getAudioContext().decodeAudioData(arrayBuffer.slice(0));
		return scanSuccessBuffer.value;
	}

	async function playScanSuccessBufferSound(): Promise<void> {
		const context = getAudioContext();
		if (context.state === "suspended") {
			await context.resume();
		}

		activeScanSuccessSource.value?.stop();
		activeScanSuccessSource.value?.disconnect();

		const source = context.createBufferSource();
		const gainNode = context.createGain();
		source.buffer = await buildScanSuccessPlaybackBuffer();
		gainNode.gain.value = sound.value.volume / 100;
		source.connect(gainNode);
		gainNode.connect(context.destination);
		source.onended = () => {
			if (activeScanSuccessSource.value === source) {
				activeScanSuccessSource.value = null;
			}
			source.disconnect();
			gainNode.disconnect();
		};
		activeScanSuccessSource.value = source;
		source.start(0);
	}

	async function buildScanSuccessPlaybackBuffer(): Promise<AudioBuffer> {
		const sourceBuffer = await loadScanSuccessBuffer();
		const context = getAudioContext();
		const warmupFrameCount = Math.max(1, Math.round(context.sampleRate * SCAN_SUCCESS_WARMUP_HEAD_MS / 1000));
		const outputBuffer = context.createBuffer(
			sourceBuffer.numberOfChannels,
			sourceBuffer.length + warmupFrameCount,
			sourceBuffer.sampleRate
		);

		for (let channelIndex = 0; channelIndex < sourceBuffer.numberOfChannels; channelIndex += 1) {
			const outputData = outputBuffer.getChannelData(channelIndex);
			const sourceData = sourceBuffer.getChannelData(channelIndex);
			const warmupSourceLength = Math.min(sourceData.length, warmupFrameCount);
			// 预热头不能是纯静音；纯静音对这类 Windows 问题无效。
			for (let frameIndex = 0; frameIndex < warmupFrameCount; frameIndex += 1) {
				const sourceIndex = frameIndex % warmupSourceLength;
				outputData[frameIndex] = sourceData[sourceIndex] * SCAN_SUCCESS_WARMUP_GAIN;
			}
			outputData.set(sourceData, warmupFrameCount);
		}

		return outputBuffer;
	}

	async function playSound(type: SoundType): Promise<void> {
		if (type === "scanSuccess") {
			await playScanSuccessBufferSound();
			return;
		}

		loadSoundPlayers();
		if (!sound.value[type] || !soundPlayerMap.value) {
			return;
		}

		const player = soundPlayerMap.value[type];
		player.pause();
		player.muted = false;
		player.volume = sound.value.volume / 100;
		player.currentTime = 0;
		await player.play();
	}

	async function playScanSuccessSound(): Promise<void> {
		await playSound("scanSuccess");
	}

	async function playRegisterSuccessSound(): Promise<void> {
		await playSound("registerSuccess");
	}

	return {
		sound,
		setSound,
		loadSoundPlayers,
		unlockSoundPlayers,
		playScanSuccessSound,
		playRegisterSuccessSound
	};
});