package view

import (
	"encoding/json"
	"fmt"
	"net/http"

	"arimelody-web/admin"
	"arimelody-web/global"
	"arimelody-web/music/model"
	db "arimelody-web/music/controller"
	"arimelody-web/templates"
)

type (
    Track struct {
        Title       string  `json:"title"`
        Description string  `json:"description"`
        Lyrics      string  `json:"lyrics"`
    }

    Credit struct {
        *model.Artist
        Role    string  `json:"role"`
        Primary bool    `json:"primary"`
    }

    Release struct {
        *model.Release
        Tracks  []Track             `json:"tracks"`
        Credits []Credit            `json:"credits"`
        Links   map[string]string   `json:"links"`
    }
)

func ServeRelease(release *model.Release) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        // only allow authorised users to view hidden releases
        authorised := admin.GetSession(r) != nil
        if !authorised && !release.Visible {
            http.NotFound(w, r)
            return
        }

        response := Release{
            Release: release,
            Tracks: []Track{},
            Credits: []Credit{},
            Links: make(map[string]string),
        }

        if authorised || release.IsReleased() {
            // get credits
            credits, err := db.GetReleaseCredits(global.DB, release.ID)
            if err != nil {
                fmt.Printf("FATAL: Failed to serve release %s: Credits: %s\n", release.ID, err)
                http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
                return
            }
            for _, credit := range credits {
                artist, err := db.GetArtist(global.DB, credit.Artist.ID)
                if err != nil {
                    fmt.Printf("FATAL: Failed to serve release %s: Artists: %s\n", release.ID, err)
                    http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
                    return
                }

                response.Credits = append(response.Credits, Credit{
                    Artist: artist,
                    Role: credit.Role,
                    Primary: credit.Primary,
                })
            }

            // get tracks
            tracks, err := db.GetReleaseTracks(global.DB, release.ID)
            if err != nil {
                fmt.Printf("FATAL: Failed to serve release %s: Tracks: %s\n", release.ID, err)
                http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
                return
            }
            for _, track := range tracks {
                response.Tracks = append(response.Tracks, Track{
                    Title: track.Title,
                    Description: track.Description,
                    Lyrics: track.Lyrics,
                })
            }

            // get links
            links, err := db.GetReleaseLinks(global.DB, release.ID)
            if err != nil {
                fmt.Printf("FATAL: Failed to serve release %s: Links: %s\n", release.ID, err)
                http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
                return
            }
            for _, link := range links {
                response.Links[link.Name] = link.URL
            }
        }

		w.Header().Add("Content-Type", "application/json")
        err := json.NewEncoder(w).Encode(response)
		if err != nil {
			http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
			return
		}
	})
}

func ServeGateway(release *model.Release) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        // only allow authorised users to view hidden releases
        authorised := admin.GetSession(r) != nil
        if !authorised && !release.Visible {
            http.NotFound(w, r)
            return
        }

        response := *release

        if authorised || release.IsReleased() {
            response.Tracks = release.Tracks
            response.Credits = release.Credits
            response.Links = release.Links
        }

        err := templates.Pages["music-gateway"].Execute(w, response)

        if err != nil {
            fmt.Printf("Error rendering music gateway for %s: %s\n", release.ID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }
    })
}