var moment = require("moment");
var _ = require("lodash");
var fs = require('fs');
var mkdirp = require('mkdirp');
var jade = require('jade');
var marked = require('marked');
var path = require('path');
var schemas = require('./schemas.js');
var config = require("./config.js").config;
var sharp = require('sharp');

var Photo = function(data) {
    this.data = this.sanitize(data);
}

////////////////////////////////////////////////////////////////////////////////////////
// Prototype Setup
////////////////////////////////////////////////////////////////////////////////////////

Photo.prototype.data = {}

Photo.prototype.get = function (name) {
    return this.data[name];
}

Photo.prototype.set = function (name, value) {
    this.data[name] = value;
}

Photo.prototype.sanitize = function (data) {
    data = data || {};
    schema = schemas.photo;
    return _.pick(_.defaults(data, schema), _.keys(schema));
}

Photo.prototype.save = function (date, callback) {
    var self = this;
    if (date) {
        this.set('updatedDate', date);
    } else {
        this.set("updatedDate", new Date());
    }
    this.data = this.sanitize(this.data);
    db.collection("photos").update({uuid: this.get("uuid")}, this.data, {upsert: true}, function(err) {
        callback(err);
    });
}

////////////////////////////////////////////////////////////////////////////////////////
// Prototype Functions
////////////////////////////////////////////////////////////////////////////////////////

// Parse a string of tags
// Returns a list of tags
Photo.prototype.tagPhoto = function(str) {
    this.set("tags", []);

    // we don't need no stinking commas
    var str = str.replace(/,/g,'');

    // remove accents, swap ñ for n, etc
    var from = "àáäâèéëêìíïîòóöôùúüûñç·/,:;&%";
    var to   = "aaaaeeeeiiiioooouuuunc-------";
    for (var i=0, l=from.length ; i<l ; i++) {
        str = str.replace(new RegExp(from.charAt(i), 'g'), to.charAt(i));
    }

    // Make into a sorted, unique array
    var l = str.split(" ");
    var list = []
    for (i = 0; i < l.length; i ++) {
        if (l[i]) {
            list[i] = l[i].toLowerCase().trim()
        }
    }
    list = list.sort();
    var unique = list.filter(function(elem, index, self) {
        return index == self.indexOf(elem);
    })

    // Push these into the post.
    for (var i = 0, size = unique.length; i < size; i++) {
        if (unique[i]) {
            this.data.tags.push({name: list[i]});
        }
    }
}

// Function to get a YYYY-MM-DD format of the current photoDate
// Arguments: None
// Returns: Date as String
Photo.prototype.getShortDate = function () {
    return moment(this.get("photoDate")).format("YYYY-MM-DD");
}

// Function to return rendered markdown of a photo
// Arguments: None
// Returns: Content as String
Photo.prototype.renderMarkdown = function () {
    return marked(this.get("markdown"));
}

// Function to get the relative url of a photo, this sets the permalink structure
// Arguments: None
// Returns: URL as String
Photo.prototype.getURL = function () {
    var url  = "/photos/";
        url += moment(this.get("photoDate")).format("YYYY/MM/");
        url += this.get("slug") + '/';
    return url;
}

// Function to return the path of the photo index file
// Arguments: None
// Returns: Path as a string
Photo.prototype.getIndexPath = function () {
    var file = path.join(this.getDirectory(),'index.html');
    return file;
}

// Function to return the photo build directory
// Arguments: None
// Returns: Directory path as String
Photo.prototype.getDirectory = function () {
    var dir = path.join(config.buildDir,this.getURL());
    return dir;
}


// Build a slug from a title string
// Arguments: None
// Returns: Photo Slug as String
Photo.prototype.makeSlug = function () {
      str = this.get("title").replace(/^\s+|\s+$/g, ''); // trim
      str = str.toLowerCase();
      str = str.trim();

      // remove accents, swap ñ for n, etc
      var from = "àáäâèéëêìíïîòóöôùúüûñç·/_,:;&";
      var to   = "aaaaeeeeiiiioooouuuunc-------";
      for (var i=0, l=from.length ; i<l ; i++) {
        str = str.replace(new RegExp(from.charAt(i), 'g'), to.charAt(i));
      }

      str = str.replace(/[^a-z0-9 -]/g, '') // remove invalid chars
        .replace(/\s+/g, '-') // collapse whitespace and replace by -
        .replace(/-+/g, '-'); // collapse dashes

      return str;
};

// Function to generate static renderings of a particular post.
// Arguments: Callback function
// Returns: err
Photo.prototype.build = function (callback) {
    console.log('Rendering photo: '+this.get("title"));
    var jadeOut = jade.renderFile('views/render-photo.jade', {
        pretty: true,
        photo: this
    });

    console.log('Creating directory: '+ this.getDirectory());

    self = this;

    mkdirp(self.getDirectory(), function (err) {
        if (err) console.log(err);
        for (var size in config.imageSizes) {
            console.log('Generating '+size+' for '+self.get("slug"));
            (function (size) {
                var outFile = path.join(self.getDirectory(),size+'.'+self.get("extension"));
                sharp(self.get('masterPath'))
                    .resize(config.imageSizes[size], config.imageSizes[size])
                    .max()
                    .quality(95)
                    .withoutEnlargement()
                    .toFile(outFile, function(err) {
                        if (!err) {
                            console.log(self.get("slug")+' '+size+' generated.');
                        } else {
                            console.log(self.get("slug")+' resize failed.');
                        }
                    });
            })(size);
        }

        fs.writeFile(self.getIndexPath(), jadeOut, 'utf-8', function (err) {
            self.set('lastBuildDate', new Date());
            self.save(self.get('lastBuildDate'), function (err) {
                callback(err);
            });
        });
    });


}


////////////////////////////////////////////////////////////////////////////////////////
// Independent Functions
////////////////////////////////////////////////////////////////////////////////////////



// Function to find the most recent photo generation.
// Returns a date object
Photo.getLastBuildDate = function (callback) {
    db.collection("photos").findOne({}, {lastBuildDate: 1}, {sort: {lastBuildDate: -1}},
        function(err, doc) {
            callback(err, doc.lastBuildDate);
        }
    )
};

// Function to find the most recent photo upload date.
// Returns a date object
Photo.getLastUploadDate = function (callback) {
    db.collection("photos").findOne({}, {lastUploadDate: 1}, {sort: {lastUploadDate: -1}},
        function (err, doc) {
            callback(err, doc.lastUploadDate);
        }
    )
};


// Get a specific photo by it's UUID
// Inputs: UUID as String
// Returns: Photo object
Photo.getByUUID = function (uuid, callback) {
    db.collection("photos").findOne({uuid: uuid}, function(err, doc) {
        callback(err, new Photo(doc));
    });
}

// Function to get a count of current photos
// Inputs: Callback function
// Returns: Count of photos as integer
Photo.countPhotos = function (callback) {
    db.collection("photos").find({}).count(function (err, count) {
        if (err) console.log(err);
        callback(err, count);
    });
}

// Function to get a list of posts of a certain count and starting at an offset
// Count and start are optional, when start is specified count must be specified.
// Returns a list of post objects
Photo.getPhotos = function (count, start, callback) {
    if (typeof callback === undefined) {
        if (typeof start === undefined) {
            callback = count;
            count = undefined;
            start = undefined;
        }
        else {
            callback = start;
            start = undefined;
        }
    }

    var options = {}
    if (start) options.skip=start;
    if (count) options.limit=count;
    options.sort = [['photoDate', 'desc'],['title', 'asc']];

    db.collection("photos").find({},options).toArray( function(err, docs) {
        if (err) console.log(err);
        photos = [];
        for (i=0; i<docs.length; i++) {
            photos.push(new Photo(docs[i]));
        }
        callback(null, photos);
    });
}

// Function to find photos that need to be built
// Inputs: Callback function
// Returns: list of Photo objects
Photo.getNeedsBuild = function (callback) {
    db.collection("photos").find({
            $where: "(this.lastBuildDate < this.updatedDate) && this.published"
        }).toArray(
        function (err, docs) {
            if (err) console.log(err);
            photos = [];
            if (docs) {
                for (i=0; i<docs.length; i++) {
                    photos.push(new Photo(docs[i]));
                }
                callback(null, photos);
            } else {
                callback('No photos need to be built.', null);
            }
        }
    );
}

// Function to find photos that need to be uploaded
// Inputs: Callback function
// Returns: List of Photo objects
Photo.getNeedsUpload = function (callback) {
    db.collection("photos").find({
            $where: '(this.lastUploadDate < this.updatedDate) && \
                     (this.lastBuildDate >= this.updatedDate) && \
                      this.published'
        }).toArray( function (err, docs) {
            if (err) console.log(err);
            photos = [];
            if (docs) {
                for (i=0; i<docs.length; i++) {
                    photos.push(new Photo(docs[i]));
                }
                callback(null, photos);
            } else {
                callback("No photos require upload.", null);
            }
        }
    );
}

// Export the Photo object for external use.
module.exports = Photo;