var app = {
    srcPath:'src/',
    buildPath:'build/',
    distPath:'dist/'
}

/*1.引入gulp*/
var gulp = require('gulp');
var less = require('gulp-less');
var cssmin = require('gulp-cssmin');
var uglify = require('gulp-uglify');
var concat = require('gulp-concat');
var connect = require('gulp-connect');
var imagemin = require('gulp-imagemin');
var open = require('open');


gulp.task('lib',function () {
   gulp.src('bower_components/**/*.js')
       .pipe(gulp.dest(app.buildPath+'lib'))
       .pipe(gulp.dest(app.distPath+'lib'))
       .pipe(connect.reload())
});



/*2.定义任务 把所有html文件移动另一个位置*/
gulp.task('html',function () {
    /*要操作哪些文件 确定源文件地址*/
    gulp.src(app.srcPath+'**/*.html')  /*src下所有目录下的所有.html文件*/
        .pipe(gulp.dest(app.buildPath))
        .pipe(gulp.dest(app.distPath))
        .pipe(connect.reload())
});
/*3.执行任务 通过命令行。gulp 任务名称*/



/*定义编译less任务  下载对应的插件 gulp-less
* 把less文件转成css放到build
* */
gulp.task('less',function () {
    gulp.src(app.srcPath+'style/index.less')
        .pipe(less())
        .pipe(gulp.dest(app.buildPath+'css/'))
        /*经过压缩，放到dist目录当中*/
        .pipe(cssmin())
        .pipe(gulp.dest(app.distPath+'css/'))
        .pipe(connect.reload())
});

/*合并js*/
gulp.task('js',function () {
   gulp.src(app.srcPath+'js/**/*.js')
       .pipe(concat('index.js'))
       .pipe(gulp.dest(app.buildPath+'js/'))
       .pipe(uglify())
       .pipe(gulp.dest(app.distPath+'js'))
       .pipe(connect.reload())
});

/*压缩图片*/
gulp.task('image',function () {
     gulp.src(app.srcPath+'images/**/*')
         .pipe(gulp.dest(app.buildPath+'images'))
         .pipe(imagemin())
         .pipe(gulp.dest(app.distPath+'images'))
         .pipe(connect.reload())
});

/*同时执行多个任务*/
gulp.task('build',['less','html','js','image','lib']);

gulp.task('server',['build'],function () {
    /*设置服务器*/
    connect.server({
        root:[app.buildPath],
        livereload:true,
        port:9999
    })
    /*监听哪些文件*/
    gulp.watch('bower_components/**/*',['lib']);
    gulp.watch(app.srcPath+'**/*.html',['html']);
    gulp.watch(app.srcPath+'js/**/*.js',['js']);
    gulp.watch(app.srcPath+'images/**/*',['image']);
    gulp.watch(app.srcPath+'style/**/*.less',['less']);

    open('http://localhost:9999');
});

/*定义默认任务*/
gulp.task('default',['server']);