import { AnimationUtils } from './AnimationUtils.js';
import { KeyframeTrack } from './KeyframeTrack.js';
import { BooleanKeyframeTrack } from './tracks/BooleanKeyframeTrack.js';
import { ColorKeyframeTrack } from './tracks/ColorKeyframeTrack.js';
import { NumberKeyframeTrack } from './tracks/NumberKeyframeTrack.js';
import { QuaternionKeyframeTrack } from './tracks/QuaternionKeyframeTrack.js';
import { StringKeyframeTrack } from './tracks/StringKeyframeTrack.js';
import { VectorKeyframeTrack } from './tracks/VectorKeyframeTrack.js';
import * as MathUtils from '../math/MathUtils.js';
import { NormalAnimationBlendMode } from '../constants.js';

class AnimationClip {
	constructor(name, duration = -1, tracks, blendMode = NormalAnimationBlendMode) {
		this.name = name;
		this.tracks = tracks;
		this.duration = duration;
		this.blendMode = blendMode;

		this.uuid = MathUtils.generateUUID();

		// this means it should figure out its duration by scanning the tracks
		if (this.duration < 0) {
			this.resetDuration();
		}
	}

	static parse(json) {
		const tracks = [],
			jsonTracks = json.tracks,
			frameTime = 1.0 / (json.fps || 1.0);

		for (let i = 0, n = jsonTracks.length; i !== n; ++i) {
			tracks.push(parseKeyframeTrack(jsonTracks[i]).scale(frameTime));
		}

		const clip = new this(json.name, json.duration, tracks, json.blendMode);
		clip.uuid = json.uuid;

		return clip;
	}

	static toJSON(clip) {
		const tracks = [],
			clipTracks = clip.tracks;

		const json = {
			name: clip.name,
			duration: clip.duration,
			tracks: tracks,
			uuid: clip.uuid,
			blendMode: clip.blendMode,
		};

		for (let i = 0, n = clipTracks.length; i !== n; ++i) {
			tracks.push(KeyframeTrack.toJSON(clipTracks[i]));
		}

		return json;
	}

	static CreateFromMorphTargetSequence(name, morphTargetSequence, fps, noLoop) {
		const numMorphTargets = morphTargetSequence.length;
		const tracks = [];

		for (let i = 0; i < numMorphTargets; i++) {
			let times = [];
			let values = [];

			times.push((i + numMorphTargets - 1) % numMorphTargets, i, (i + 1) % numMorphTargets);

			values.push(0, 1, 0);

			const order = AnimationUtils.getKeyframeOrder(times);
			times = AnimationUtils.sortedArray(times, 1, order);
			values = AnimationUtils.sortedArray(values, 1, order);

			// if there is a key at the first frame, duplicate it as the
			// last frame as well for perfect loop.
			if (!noLoop && times[0] === 0) {
				times.push(numMorphTargets);
				values.push(values[0]);
			}

			tracks.push(new NumberKeyframeTrack('.morphTargetInfluences[' + morphTargetSequence[i].name + ']', times, values).scale(1.0 / fps));
		}

		return new this(name, -1, tracks);
	}

	static findByName(objectOrClipArray, name) {
		let clipArray = objectOrClipArray;

		if (!Array.isArray(objectOrClipArray)) {
			const o = objectOrClipArray;
			clipArray = (o.geometry && o.geometry.animations) || o.animations;
		}

		for (let i = 0; i < clipArray.length; i++) {
			if (clipArray[i].name === name) {
				return clipArray[i];
			}
		}

		return null;
	}

	static CreateClipsFromMorphTargetSequences(morphTargets, fps, noLoop) {
		const animationToMorphTargets = {};

		// tested with https://regex101.com/ on trick sequences
		// such flamingo_flyA_003, flamingo_run1_003, crdeath0059
		const pattern = /^([\w-]*?)([\d]+)$/;

		// sort morph target names into animation groups based
		// patterns like Walk_001, Walk_002, Run_001, Run_002
		for (let i = 0, il = morphTargets.length; i < il; i++) {
			const morphTarget = morphTargets[i];
			const parts = morphTarget.name.match(pattern);

			if (parts && parts.length > 1) {
				const name = parts[1];

				let animationMorphTargets = animationToMorphTargets[name];

				if (!animationMorphTargets) {
					animationToMorphTargets[name] = animationMorphTargets = [];
				}

				animationMorphTargets.push(morphTarget);
			}
		}

		const clips = [];

		for (const name in animationToMorphTargets) {
			clips.push(this.CreateFromMorphTargetSequence(name, animationToMorphTargets[name], fps, noLoop));
		}

		return clips;
	}

	// parse the animation.hierarchy format
	static parseAnimation(animation, bones) {
		if (!animation) {
			console.error('THREE.AnimationClip: No animation in JSONLoader data.');
			return null;
		}

		const addNonemptyTrack = function (trackType, trackName, animationKeys, propertyName, destTracks) {
			// only return track if there are actually keys.
			if (animationKeys.length !== 0) {
				const times = [];
				const values = [];

				AnimationUtils.flattenJSON(animationKeys, times, values, propertyName);

				// empty keys are filtered out, so check again
				if (times.length !== 0) {
					destTracks.push(new trackType(trackName, times, values));
				}
			}
		};

		const tracks = [];

		const clipName = animation.name || 'default';
		const fps = animation.fps || 30;
		const blendMode = animation.blendMode;

		// automatic length determination in AnimationClip.
		let duration = animation.length || -1;

		const hierarchyTracks = animation.hierarchy || [];

		for (let h = 0; h < hierarchyTracks.length; h++) {
			const animationKeys = hierarchyTracks[h].keys;

			// skip empty tracks
			if (!animationKeys || animationKeys.length === 0) continue;

			// process morph targets
			if (animationKeys[0].morphTargets) {
				// figure out all morph targets used in this track
				const morphTargetNames = {};

				let k;

				for (k = 0; k < animationKeys.length; k++) {
					if (animationKeys[k].morphTargets) {
						for (let m = 0; m < animationKeys[k].morphTargets.length; m++) {
							morphTargetNames[animationKeys[k].morphTargets[m]] = -1;
						}
					}
				}

				// create a track for each morph target with all zero
				// morphTargetInfluences except for the keys in which
				// the morphTarget is named.
				for (const morphTargetName in morphTargetNames) {
					const times = [];
					const values = [];

					for (let m = 0; m !== animationKeys[k].morphTargets.length; ++m) {
						const animationKey = animationKeys[k];

						times.push(animationKey.time);
						values.push(animationKey.morphTarget === morphTargetName ? 1 : 0);
					}

					tracks.push(new NumberKeyframeTrack('.morphTargetInfluence[' + morphTargetName + ']', times, values));
				}

				duration = morphTargetNames.length * (fps || 1.0);
			} else {
				// ...assume skeletal animation

				const boneName = '.bones[' + bones[h].name + ']';

				addNonemptyTrack(VectorKeyframeTrack, boneName + '.position', animationKeys, 'pos', tracks);

				addNonemptyTrack(QuaternionKeyframeTrack, boneName + '.quaternion', animationKeys, 'rot', tracks);

				addNonemptyTrack(VectorKeyframeTrack, boneName + '.scale', animationKeys, 'scl', tracks);
			}
		}

		if (tracks.length === 0) {
			return null;
		}

		const clip = new this(clipName, duration, tracks, blendMode);

		return clip;
	}

	resetDuration() {
		const tracks = this.tracks;
		let duration = 0;

		for (let i = 0, n = tracks.length; i !== n; ++i) {
			const track = this.tracks[i];

			duration = Math.max(duration, track.times[track.times.length - 1]);
		}

		this.duration = duration;

		return this;
	}

	trim() {
		for (let i = 0; i < this.tracks.length; i++) {
			this.tracks[i].trim(0, this.duration);
		}

		return this;
	}

	validate() {
		let valid = true;

		for (let i = 0; i < this.tracks.length; i++) {
			valid = valid && this.tracks[i].validate();
		}

		return valid;
	}

	optimize() {
		for (let i = 0; i < this.tracks.length; i++) {
			this.tracks[i].optimize();
		}

		return this;
	}

	clone() {
		const tracks = [];

		for (let i = 0; i < this.tracks.length; i++) {
			tracks.push(this.tracks[i].clone());
		}

		return new this.constructor(this.name, this.duration, tracks, this.blendMode);
	}

	toJSON() {
		return this.constructor.toJSON(this);
	}
}

function getTrackTypeForValueTypeName(typeName) {
	switch (typeName.toLowerCase()) {
		case 'scalar':
		case 'double':
		case 'float':
		case 'number':
		case 'integer':
			return NumberKeyframeTrack;

		case 'vector':
		case 'vector2':
		case 'vector3':
		case 'vector4':
			return VectorKeyframeTrack;

		case 'color':
			return ColorKeyframeTrack;

		case 'quaternion':
			return QuaternionKeyframeTrack;

		case 'bool':
		case 'boolean':
			return BooleanKeyframeTrack;

		case 'string':
			return StringKeyframeTrack;
	}

	throw new Error('THREE.KeyframeTrack: Unsupported typeName: ' + typeName);
}

function parseKeyframeTrack(json) {
	if (json.type === undefined) {
		throw new Error('THREE.KeyframeTrack: track type undefined, can not parse');
	}

	const trackType = getTrackTypeForValueTypeName(json.type);

	if (json.times === undefined) {
		const times = [],
			values = [];

		AnimationUtils.flattenJSON(json.keys, times, values, 'value');

		json.times = times;
		json.values = values;
	}

	// derived classes can define a static parse method
	if (trackType.parse !== undefined) {
		return trackType.parse(json);
	} else {
		// by default, we assume a constructor compatible with the base
		return new trackType(json.name, json.times, json.values, json.interpolation);
	}
}

export { AnimationClip };