package api

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

	"arimelody.me/arimelody.me/admin"
	"arimelody.me/arimelody.me/global"
	"arimelody.me/arimelody.me/music/model"
	controller "arimelody.me/arimelody.me/music/controller"
)

func ServeCatalog() http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        releases := []*model.Release{}
        authorised := admin.GetSession(r) != nil
        for _, release := range global.Releases {
            if !release.IsReleased() && !authorised {
                continue
            }
            releases = append(releases, release)
        }

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

func CreateRelease() http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        if r.Method != http.MethodPost {
            http.NotFound(w, r)
            return
        }

        type PostReleaseBody struct {
            ID              string              `json:"id"`
            Visible         bool                `json:"visible"`
            Title           string              `json:"title"`
            Description     string              `json:"description"`
            ReleaseType     model.ReleaseType   `json:"type"`
            ReleaseDate     time.Time           `json:"releaseDate"`
            Artwork         string              `json:"artwork"`
            Buyname         string              `json:"buyname"`
            Buylink         string              `json:"buylink"`
        }

        var data PostReleaseBody
        err := json.NewDecoder(r.Body).Decode(&data)
        if err != nil {
            http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
            return
        }

        if data.ID == "" {
            http.Error(w, "Release ID cannot be empty\n", http.StatusBadRequest)
            return
        }
        if data.Title == "" {
            http.Error(w, "Release title cannot be empty\n", http.StatusBadRequest)
            return
        }
        if data.ReleaseDate.Unix() == 0 {
            http.Error(w, "Release date cannot be empty or 0\n", http.StatusBadRequest)
            return
        }

        if global.GetRelease(data.ID) != nil {
            http.Error(w, fmt.Sprintf("Release %s already exists\n", data.ID), http.StatusBadRequest)
            return
        }

        var release = model.Release{
            ID: data.ID,
            Visible: data.Visible,
            Title: data.Title,
            Description: data.Description,
            ReleaseType: data.ReleaseType,
            ReleaseDate: data.ReleaseDate,
            Artwork: data.Artwork,
            Buyname: data.Buyname,
            Buylink: data.Buylink,
            Links: []*model.Link{},
            Credits: []*model.Credit{},
            Tracks: []*model.Track{},
        }

        err = controller.CreateReleaseDB(global.DB, &release)
        if err != nil {
            fmt.Printf("Failed to create release %s: %s\n", release.ID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }

        global.Releases = append([]*model.Release{&release}, global.Releases...)

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

func DeleteRelease() http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        if r.Method != http.MethodDelete {
            http.NotFound(w, r)
            return
        }

        if r.URL.Path == "/" {
            http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
            return
        }

        var releaseID = r.URL.Path[1:]
        var release = global.GetRelease(releaseID)
        if release == nil {
            http.Error(w, fmt.Sprintf("Release %s does not exist\n", releaseID), http.StatusBadRequest)
            return
        }

        err := controller.DeleteReleaseDB(global.DB, release)
        if err != nil {
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }

        global.Releases = func () []*model.Release {
            var releases = []*model.Release{}
            for _, r := range global.Releases {
                if r.ID == releaseID { continue }
                releases = append(releases, r)
            }
            return releases            
        }()

        w.WriteHeader(200)
        w.Write([]byte(fmt.Sprintf("Release %s has been deleted\n", release.ID)))
    })
}