import { Context, Next } from 'koa';
import Router from 'koa-router';
import {ContentAccessor, isContentContent} from './../model/contents';
import {QueryListOption} from './../model/contents';
import {ParseQueryNumber, ParseQueryArray, ParseQueryBoolean} from './util'
import {sendError} from './error_handler';
import { createContentReferrer } from '../content/referrer';
import { join } from 'path';
import {AllContentRouter} from './all';

const ContentIDHandler = (controller: ContentAccessor) => async (ctx: Context,next: Next)=>{
    const num = Number.parseInt(ctx.params['num']);
    let content = await controller.findById(num,true);
    if (content == undefined){
        sendError(404,"content does not exist.");
        return;
    }
    ctx.body = content;
    ctx.type = 'json';
    return await next();
};
const ContentTagIDHandler = (controller: ContentAccessor) => async (ctx: Context,next: Next)=>{
    const num = Number.parseInt(ctx.params['num']);
    let content = await controller.findById(num,true);
    if (content == undefined){
        sendError(404,"content does not exist.");
        return;
    }
    ctx.body = content.tags || [];
    ctx.type = 'json';
    return await next();
};
const ContentQueryHandler = (controller : ContentAccessor) => async (ctx: Context,next: Next)=>{
    const limit = ParseQueryNumber(ctx.query['limit']);
    const cursor = ParseQueryNumber(ctx.query['cursor']);
    const word: string|undefined = ctx.query['word'];
    const offset = ParseQueryNumber(ctx.query['offset']);
    if(limit === NaN || cursor === NaN || offset === NaN){
        sendError(400,"parameter limit, cursor or offset is not a number");
    }
    const allow_tag = ParseQueryArray(ctx.query['allow_tag[]']);
    let [ok,use_offset] = ParseQueryBoolean(ctx.query['use_offset']);
    if(!ok){
        sendError(400,"use_offset must be true or false.");
        return;
    }
    const option :QueryListOption = {
        limit: limit,
        allow_tag: allow_tag,
        word: word,
        cursor: cursor,
        eager_loading: true,
        offset: offset,
        use_offset: use_offset
    };
    let content = await controller.findList(option);
    ctx.body = content;
    ctx.type = 'json';
}
const CreateContentHandler = (controller : ContentAccessor) => async (ctx: Context, next: Next) => {
    const content_desc = ctx.request.body;
    if(!isContentContent(content_desc)){
        sendError(400,"it is not a valid format");
        return;
    }
    const id = await controller.add(content_desc);
    ctx.body = {"ret":id};
    ctx.type = 'json';
};
const AddTagHandler = (controller: ContentAccessor)=>async (ctx: Context, next: Next)=>{
    let tag_name = ctx.params['tag'];
    const num = Number.parseInt(ctx.params['num']);
    if(typeof tag_name === undefined){
        sendError(400,"??? Unreachable");
    }
    tag_name = String(tag_name);
    const c = await controller.findById(num);
    if(c === undefined){
        sendError(404);
        return;
    }
    const r = await controller.addTag(c,tag_name);
    ctx.body = {ret:r}
    ctx.type = 'json';
};
const DelTagHandler = (controller: ContentAccessor)=>async (ctx: Context, next: Next)=>{
    let tag_name = ctx.params['tag'];
    const num = Number.parseInt(ctx.params['num']);
    if(typeof tag_name === undefined){
        sendError(400,"?? Unreachable");
    }
    tag_name = String(tag_name);
    const c = await controller.findById(num);
    if(c === undefined){
        sendError(404);
        return;
    }
    const r = await controller.delTag(c,tag_name);
    ctx.body = {ret:r}
    ctx.type = 'json';
}
const DeleteContentHandler = (controller : ContentAccessor) => async (ctx: Context, next: Next) => {
    const num = Number.parseInt(ctx.params['num']);
    const r = await controller.del(num);
    ctx.body = {"ret":r};
    ctx.type = 'json';
};
const ContentHandler = (controller : ContentAccessor) => async (ctx:Context, next:Next) => {
    const num = Number.parseInt(ctx.params['num']);
    let content = await controller.findById(num,true);
    if (content == undefined){
        sendError(404,"content does not exist.");
        return;
    }
    const path = join(content.basepath,content.filename);
    ctx.state['content'] = createContentReferrer(content.content_type,path,content.additional);
    await next();
};

export const getContentRouter = (controller: ContentAccessor)=>{
    const ret = new Router();
    ret.get("/search",ContentQueryHandler(controller));
    ret.get("/:num(\\d+)",ContentIDHandler(controller));
    ret.use("/:num(\\d+)/:content_type");
    ret.post("/",CreateContentHandler(controller));
    ret.get("/:num(\\d+)/tags",ContentTagIDHandler(controller));
    ret.post("/:num(\\d+)/tags/:tag",AddTagHandler(controller));
    ret.del("/:num(\\d+)/tags/:tag",DelTagHandler(controller));
    ret.del("/:num(\\d+)",DeleteContentHandler(controller));
    ret.all("/:num(\\d+)/(.*)",ContentHandler(controller));
    ret.use("/:num",(new AllContentRouter).routes());
    return ret;
}

export default getContentRouter;