/**
 * Copyright 2017 Google Inc. All rights reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

// @ts-check

/** @typedef {import('../markdown').MarkdownNode} MarkdownNode */

/**
 * @typedef {{
  *   name: string,
  *   args: ParsedType | null,
  *   retType: ParsedType | null,
  *   template: ParsedType | null,
  *   union: ParsedType | null,
  *   next: ParsedType | null,
  * }} ParsedType
  */
 
class Documentation {
  /**
   * @param {!Array<!Documentation.Class>} classesArray
   */
  constructor(classesArray) {
    this.classesArray = classesArray;
    /** @type {!Map<string, !Documentation.Class>} */
    this.classes = new Map();
    for (const cls of classesArray)
      this.classes.set(cls.name, cls);
  }
}

Documentation.Class = class {
  /**
   * @param {string} name
   * @param {!Array<!Documentation.Member>} membersArray
   * @param {?string=} extendsName
   * @param {MarkdownNode[]=} spec
   * @param {string[]=} templates
   */
  constructor(name, membersArray, extendsName = null, spec = undefined, templates = []) {
    this.name = name;
    this.membersArray = membersArray;
    this.spec = spec;
    this.extends = extendsName;
    this.templates = templates;
    this.comment =  '';
    this.index();
    const match = name.match(/(JS|CDP|[A-Z])(.*)/);
    this.varName = match[1].toLowerCase() + match[2];
  }

  index() {
    /** @type {!Map<string, !Documentation.Member>} */
    this.members = new Map();
    /** @type {!Map<string, !Documentation.Member>} */
    this.properties = new Map();
    /** @type {!Array<!Documentation.Member>} */
    this.propertiesArray = [];
    /** @type {!Map<string, !Documentation.Member>} */
    this.methods = new Map();
    /** @type {!Array<!Documentation.Member>} */
    this.methodsArray = [];
    /** @type {!Map<string, !Documentation.Member>} */
    this.events = new Map();
    /** @type {!Array<!Documentation.Member>} */
    this.eventsArray = [];

    for (const member of this.membersArray) {
      this.members.set(member.name, member);
      if (member.kind === 'method') {
        this.methods.set(member.name, member);
        this.methodsArray.push(member);
      } else if (member.kind === 'property') {
        this.properties.set(member.name, member);
        this.propertiesArray.push(member);
      } else if (member.kind === 'event') {
        this.events.set(member.name, member);
        this.eventsArray.push(member);
      }
      member.clazz = this;
    }
  }

  validateOrder(errors, cls) {
    const members = this.membersArray;
    // Events should go first.
    let eventIndex = 0;
    for (; eventIndex < members.length && members[eventIndex].kind === 'event'; ++eventIndex);
    for (; eventIndex < members.length && members[eventIndex].kind !== 'event'; ++eventIndex);
    if (eventIndex < members.length)
      errors.push(`Events should go first. Event '${members[eventIndex].name}' in class ${cls.name} breaks order`);

    // Constructor should be right after events and before all other members.
    const constructorIndex = members.findIndex(member => member.kind === 'method' && member.name === 'constructor');
    if (constructorIndex > 0 && members[constructorIndex - 1].kind !== 'event')
      errors.push(`Constructor of ${cls.name} should go before other methods`);

    // Events should be sorted alphabetically.
    for (let i = 0; i < members.length - 1; ++i) {
      const member1 = this.membersArray[i];
      const member2 = this.membersArray[i + 1];
      if (member1.kind !== 'event' || member2.kind !== 'event')
        continue;
      if (member1.name > member2.name)
        errors.push(`Event '${member1.name}' in class ${this.name} breaks alphabetic ordering of events`);
    }

    // All other members should be sorted alphabetically.
    for (let i = 0; i < members.length - 1; ++i) {
      const member1 = this.membersArray[i];
      const member2 = this.membersArray[i + 1];
      if (member1.kind === 'event' || member2.kind === 'event')
        continue;
      if (member1.kind === 'method' && member1.name === 'constructor')
        continue;
      if (member1.name.replace(/^\$+/, '$') > member2.name.replace(/^\$+/, '$')) {
        let memberName1 = `${this.name}.${member1.name}`;
        if (member1.kind === 'method')
          memberName1 += '()';
        let memberName2 = `${this.name}.${member2.name}`;
        if (member2.kind === 'method')
          memberName2 += '()';
        errors.push(`Bad alphabetic ordering of ${this.name} members: ${memberName1} should go after ${memberName2}`);
      }
    }
  }

  /** 
   * @param {function(Documentation.Member|Documentation.Class): void} visitor
   */
  visit(visitor) {
    visitor(this);
    for (const p of this.propertiesArray)
      p.visit(visitor);
    for (const m of this.methodsArray)
      m.visit(visitor);
    for (const e of this.eventsArray)
      e.visit(visitor);
  }
};

Documentation.Member = class {
  /**
   * @param {string} kind
   * @param {string} name
   * @param {?Documentation.Type} type
   * @param {!Array<!Documentation.Member>} argsArray
   * @param {MarkdownNode[]=} spec
   * @param {boolean=} required
   * @param {string[]=} templates
   */
  constructor(kind, name, type, argsArray, spec = undefined, required = true, templates = []) {
    this.kind = kind;
    this.name = name;
    this.type = type;
    this.spec = spec;
    this.argsArray = argsArray;
    this.required = required;
    this.templates = templates;
    this.comment =  '';
    /** @type {!Map<string, !Documentation.Member>} */
    this.args = new Map();
    for (const arg of argsArray)
      this.args.set(arg.name, arg);
    /** @type {!Documentation.Class} */
    this.clazz = null;
    this.signature = this._createSignature();
  }

  clone() {
    return new Documentation.Member(this.kind, this.name, this.type, this.argsArray, this.spec, this.required, this.templates);
  }

  /**
   * @param {string} name
   * @param {!Array<!Documentation.Member>} argsArray
   * @param {?Documentation.Type} returnType
   * @param {MarkdownNode[]=} spec
   * @param {string[]=} templates
   * @return {!Documentation.Member}
   */
  static createMethod(name, argsArray, returnType, spec, templates) {
    return new Documentation.Member('method', name, returnType, argsArray, spec, undefined, templates);
  }

  /**
   * @param {string} name
   * @param {!Documentation.Type} type
   * @param {MarkdownNode[]=} spec
   * @param {boolean=} required
   * @return {!Documentation.Member}
   */
  static createProperty(name, type, spec, required) {
    return new Documentation.Member('property', name, type, [], spec, required);
  }

  /**
   * @param {string} name
   * @param {?Documentation.Type=} type
   * @param {MarkdownNode[]=} spec
   * @return {!Documentation.Member}
   */
  static createEvent(name, type = null, spec) {
    return new Documentation.Member('event', name, type, [], spec);
  }

  /** 
   * @param {function(Documentation.Member|Documentation.Class): void} visitor
   */
  visit(visitor) {
    visitor(this);
    if (this.type)
      this.type.visit(visitor);
    for (const arg of this.argsArray)
      arg.visit(visitor);
  }

  _createSignature() {
    const tokens = [];
    let hasOptional = false;
    for (const arg of this.argsArray) {
      const optional = !arg.required;
      if (tokens.length) {
        if (optional && !hasOptional)
          tokens.push(`[, ${arg.name}`);
        else
          tokens.push(`, ${arg.name}`);
      } else {
        if (optional && !hasOptional)
          tokens.push(`[${arg.name}`);
        else
          tokens.push(`${arg.name}`);
      }
      hasOptional = hasOptional || optional;
    }
    if (hasOptional)
      tokens.push(']');
    return tokens.join('');
  }
};

Documentation.Type = class {
  /**
   * @param {string} expression
   * @param {!Array<!Documentation.Member>=} properties
   * @return {Documentation.Type}
   */
  static parse(expression, properties = []) {
    expression = expression.replace(/\\\(/g, '(').replace(/\\\)/g, ')');
    const type = Documentation.Type.fromParsedType(parseTypeExpression(expression));
    if (!properties.length)
      return type;
    const types = [];
    type._collectAllTypes(types);
    let success = false;
    for (const t of types) {
      if (t.name === 'Object') {
        t.properties = properties;
        success = true;
      }
    }
    if (!success)
      throw new Error('Nested properties given, but there are no objects in type expression: ' + expression);
    return type;
  }

  /**
   * @param {ParsedType} parsedType
   * @return {Documentation.Type}
   */
  static fromParsedType(parsedType, inUnion = false) {
    if (!inUnion && parsedType.union) {
      const type = new Documentation.Type('union');
      type.union = [];
      for (let t = parsedType; t; t = t.union)
        type.union.push(Documentation.Type.fromParsedType(t, true));
      return type;
    }

    if (parsedType.args) {
      const type = new Documentation.Type('function');
      type.args = [];
      for (let t = parsedType.args; t; t = t.next)
        type.args.push(Documentation.Type.fromParsedType(t));
      type.returnType = parsedType.retType ? Documentation.Type.fromParsedType(parsedType.retType) : null;
      return type;
    }

    if (parsedType.template) {
      const type = new Documentation.Type(parsedType.name);
      type.templates = [];
      for (let t = parsedType.template; t; t = t.next)
        type.templates.push(Documentation.Type.fromParsedType(t));
      return type;
    }
    return new Documentation.Type(parsedType.name);
  }

  /**
   * @param {string} name
   * @param {!Array<!Documentation.Member>=} properties
   */
  constructor(name, properties) {
    this.name = name.replace(/^\[/, '').replace(/\]$/, '');
    this.properties = this.name === 'Object' ? properties : undefined;
    /** @type {Documentation.Type[]} | undefined */
    this.union;
    /** @type {Documentation.Type[]} | undefined */
    this.args;
    /** @type {Documentation.Type} | undefined */
    this.returnType;
    /** @type {Documentation.Type[]} | undefined */
    this.templates;
  }

  visit(visitor) {
    const types = [];
    this._collectAllTypes(types);
    for (const type of types) {
      for (const p of type.properties || [])
        p.visit(visitor);
    }
  }

  /**
   * @returns {Documentation.Member[]}
   */
  deepProperties() {
    const types = [];
    this._collectAllTypes(types);
    for (const type of types) {
      if (type.properties && type.properties.length)
        return type.properties;
    }
    return [];
  }

  /**
   * @param {Documentation.Type[]} result
   */
  _collectAllTypes(result) {
    result.push(this);
    for (const t of this.union || [])
      t._collectAllTypes(result);
    for (const t of this.args || [])
      t._collectAllTypes(result);
    for (const t of this.templates || [])
      t._collectAllTypes(result);
    if (this.returnType)
      this.returnType._collectAllTypes(result);
  }
};

/**
 * @param {string} type
 * @returns {ParsedType}
 */
function parseTypeExpression(type) {
  type = type.trim();
  let name = type;
  let next = null;
  let template = null;
  let args = null;
  let retType = null;
  let firstTypeLength = type.length;

  for (let i = 0; i < type.length; i++) {
    if (type[i] === '<') {
      name = type.substring(0, i);
      const matching = matchingBracket(type.substring(i), '<', '>');
      template = parseTypeExpression(type.substring(i + 1, i + matching - 1));
      firstTypeLength = i + matching;
      break;
    }
    if (type[i] === '(') {
      name = type.substring(0, i);
      const matching = matchingBracket(type.substring(i), '(', ')');
      args = parseTypeExpression(type.substring(i + 1, i + matching - 1));
      i = i + matching;
      if (type[i] === ':') {
        retType = parseTypeExpression(type.substring(i + 1));
        next = retType.next;
        retType.next = null;
        break;
      }
    }
    if (type[i] === '|' || type[i] === ',') {
      name = type.substring(0, i);
      firstTypeLength = i;
      break;
    }
  }
  let union = null;
  if (type[firstTypeLength] === '|')
    union = parseTypeExpression(type.substring(firstTypeLength + 1));
  else if (type[firstTypeLength] === ',')
    next = parseTypeExpression(type.substring(firstTypeLength + 1));
  return {
    name,
    args,
    retType,
    template,
    union,
    next
  };
}

/**
 * @param {string} str
 * @param {any} open
 * @param {any} close
 */
function matchingBracket(str, open, close) {
  let count = 1;
  let i = 1;
  for (; i < str.length && count; i++) {
    if (str[i] === open)
      count++;
    else if (str[i] === close)
      count--;
  }
  return i;
}

module.exports = Documentation;