'use strict';

var validator = new (require('jsonschema').Validator)();
var recase = require('recase').create({});

function deepCopy(obj) {
  if (!obj || typeof obj !== 'object') {
    return obj;
  }

  var result;
  if (Array.isArray(obj)) {
    result = [];
  } else {
    result = {};
  }
  Object.keys(obj).forEach(function (key) {
    result[key] = deepCopy(obj[key]);
  });
  return result;
}

var portSchema = { type: 'number', minimum: 1, maximum: 65535 };

var moduleSchemas = {
  // the proxy module is common to basically all categories.
  proxy: {
    type: 'object'
  , oneOf: [
      { required: [ 'address' ] }
    , { required: [ 'port' ] }
    ]
  , properties: {
      address: { type: 'string' }
    , host:    { type: 'string' }
    , port:    portSchema
    }
  }

  // redirect and static modules are for HTTP
, redirect: {
    type: 'object'
  , required: [ 'to', 'from' ]
  , properties: {
      to:     { type: 'string'}
    , from:   { type: 'string'}
    , status: { type: 'integer', minimum: 1, maximum: 999 }
  , }
  }
, static: {
    type: 'object'
  , required: [ 'root' ]
  , properties: {
      root: { type: 'string' }
    }
  }

  // the acme module is for TLS
, acme: {
    type: 'object'
  , required: [ 'email' ]
  , properties: {
      email:         { type: 'string' }
    , server:        { type: 'string' }
    , challengeType: { type: 'string' }
    }
  }
};
// forward is basically the name for the TCP proxy
moduleSchemas.forward = deepCopy(moduleSchemas.proxy);
moduleSchemas.forward.required = [ 'ports' ];
moduleSchemas.forward.properties.ports = { type: 'array', items: portSchema };

Object.keys(moduleSchemas).forEach(function (name) {
  var schema = moduleSchemas[name];
  schema.id = '/modules/'+name;
  schema.required = ['id', 'type'].concat(schema.required || []);
  schema.properties.id   = { type: 'string' };
  schema.properties.type = { type: 'string', const: name };
  validator.addSchema(schema, schema.id);
});

function addDomainsSchema(base, modList) {
  var modSchemas = modList.map(function (name) {
    return { '$ref': '/modules/'+name };
  });

  base.required = [ 'modules', 'domains' ].concat(base.required || []);
  base.properties.modules = {
    type: 'array'
  , items: {
      type: 'object'
    , required: [ 'domains' ]
    , properties: {
        domains: { type: 'array', items: { type: 'string' }, minLength: 1}
      }
    , oneOf: modSchemas
    }
  };
  base.properties.domains = {
    type: 'array'
  , items: {
      type: 'object'
    , required: [ 'id', 'names', ]
    , properties: {
        id:      { type: 'string' }
      , names:   { type: 'array', items: { type: 'string' }, minLength: 1}
      , modules: { type: 'array', items: { oneOf: modSchemas }}
      }
    }
  };
}

var httpSchema = {
  type: 'object'
, properties: {
    // These properties should be snake_case to match the API and config format
    primary_domain: { type: 'string' }
  , allow_insecure: { type: 'boolean' }
  , trust_proxy:    { type: 'boolean' }
, }
};
addDomainsSchema(httpSchema, ['proxy', 'static', 'redirect']);

var tlsSchema = {
  type: 'object'
, properties: {
    acme: {
      type: 'object'
      // These properties should be snake_case to match the API and config format
    , required: [ 'email', 'approved_domains' ]
    , properties: {
        email:            { type: 'string' }
      , server:           { type: 'string' }
      , challenge_type:   { type: 'string' }
      , approved_domains: { type: 'array', items: { type: 'string' }, minLength: 1}
      }
    }
  }
};
addDomainsSchema(tlsSchema, ['proxy', 'acme']);

var tcpSchema = {
  type: 'object'
, required: [ 'bind' ]
, properties: {
    bind:    { type: 'array', items: portSchema, minLength: 1 }
  , modules: { type: 'array', items: { '$ref': '/modules/forward' }}
  }
};

var dnsSchema = {
  type: 'object'
, properties: {
    bind:    { type: 'array', items: portSchema }
  , modules: { type: 'array', items: { '$ref': '/modules/proxy' }}
  }
};

var mdnsSchema = {
  type: 'object'
, required: [ 'port', 'broadcast', 'ttl' ]
, properties: {
    port:      portSchema
  , broadcast: { type: 'string' }
  , ttl:       { type: 'integer', minimum: 0, maximum: 2147483647 }
  }
};

var ddnsSchema = {
  type: 'object'
, properties: {
    enabled: { type: 'boolean' }
  }
};
var socks5Schema = {
  type: 'object'
, properties: {
    enabled: { type: 'boolean' }
  , port:    portSchema
  }
};

var mainSchema = {
  type: 'object'
, required: [ 'http', 'tls', 'tcp', 'dns', 'mdns', 'ddns' ]
, properties: {
    http:   httpSchema
  , tls:    tlsSchema
  , tcp:    tcpSchema
  , dns:    dnsSchema
  , mdns:   mdnsSchema
  , ddns:   ddnsSchema
  , socks5: socks5Schema
  }
, additionalProperties: false
};

module.exports.validate = function (config) {
  return validator.validate(recase.snakeCopy(config), mainSchema).errors;
};