package api

import (
	"arimelody-web/controller"
	"arimelody-web/log"
	"arimelody-web/model"
	"encoding/json"
	"fmt"
	"net/http"
	"os"
	"strings"
	"time"
)

func ServeAllBlogs(app *model.AppState) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        session := r.Context().Value("session").(*model.Session)

        onlyVisible := true
        if session != nil && session.Account != nil {
            onlyVisible = false
        }

        posts, err := controller.GetBlogPosts(app.DB, onlyVisible, -1, 0)
        if err != nil {
            fmt.Fprintf(os.Stderr, "WARN: Failed to fetch blog posts: %v\n", err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }

        type (
            ShortBlogPost struct {
                ID              string `json:"id"`
                Title           string `json:"title"`
                Description     string `json:"description"`
                Author          *model.BlogAuthor `json:"author"`
                PublishDate     time.Time `json:"publish_date"`
            }
        )
        resPosts := []*ShortBlogPost{}

        for _, post := range posts {
            resPosts = append(resPosts, &ShortBlogPost{
                ID: post.ID,
                Title: post.Title,
                Description: post.Description,
                Author: &post.Author,
                PublishDate: post.PublishDate,
            })
        }

        err = json.NewEncoder(w).Encode(resPosts)
        if err != nil {
            fmt.Fprintf(os.Stderr, "WARN: Failed to serve blog posts: %v\n", err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }
    })
}

func ServeBlog(app *model.AppState) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        session := r.Context().Value("session").(*model.Session)
        privileged := session != nil && session.Account != nil
        blogID := r.PathValue("id")

        blog, err := controller.GetBlogPost(app.DB, blogID)
        if err != nil {
            fmt.Fprintf(os.Stderr, "WARN: Failed to fetch blog post %s: %v\n", blogID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }

        if blog == nil || (!blog.Visible && !privileged) {
            http.NotFound(w, r)
            return
        }

        blog.Author.ID = blog.Author.DisplayName

        err = json.NewEncoder(w).Encode(blog)
        if err != nil {
            fmt.Fprintf(os.Stderr, "WARN: Failed to serve blog post %s: %v\n", blogID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }
    })
}

func CreateBlog(app *model.AppState) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        session := r.Context().Value("session").(*model.Session)

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

        if blog.ID == "" {
            http.Error(w, "Post ID cannot be empty", http.StatusBadRequest)
            return
        }

        if blog.Title == "" { blog.Title = blog.ID }

        if blog.PublishDate.Equal(time.Date(1, 1, 1, 0, 0, 0, 0, time.UTC)) {
            blog.PublishDate = time.Date(
                time.Now().Year(), time.Now().Month(), time.Now().Day(),
                time.Now().Hour(), time.Now().Minute(), 0, 0, time.UTC)
        }

        blog.Author.ID = session.Account.ID

        err = controller.CreateBlogPost(app.DB, &blog)
        if err != nil {
            if strings.Contains(err.Error(), "duplicate key") {
                http.Error(w, fmt.Sprintf("Post %s already exists", blog.ID), http.StatusBadRequest)
                return
            }
            fmt.Printf("WARN: Failed to create blog %s: %v\n", blog.ID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }

        app.Log.Info(log.TYPE_BLOG, "Blog post \"%s\" created by \"%s\".", blog.ID, session.Account.Username)

        blog.Author.ID = session.Account.Username
        blog.Author.DisplayName = session.Account.Username

        w.Header().Add("Content-Type", "application/json")
        w.WriteHeader(http.StatusCreated)
        err = json.NewEncoder(w).Encode(blog)
        if err != nil {
            fmt.Printf("WARN: Blog post %s created, but failed to send JSON response: %v\n", blog.ID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
        }
    })
}

func UpdateBlog(app *model.AppState) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        session := r.Context().Value("session").(*model.Session)
        blogID := r.PathValue("id")

        blog, err := controller.GetBlogPost(app.DB, blogID)
        if err != nil {
            fmt.Fprintf(os.Stderr, "WARN: Failed to fetch blog post %s: %v\n", blogID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }

        type (
            BlueskyRecord struct {
                ActorID     string `json:"actor"`
                RecordID    string `json:"record"`
            }
            FediverseStatus struct {
                AccountID   string `json:"account"`
                StatusID    string `json:"status"`
            }

            UpdatedBlog struct {
                Title           string `json:"title"`
                PublishDate     time.Time `json:"publish_date"`
                Description     string `json:"description"`
                Markdown        string `json:"markdown"`
                Bluesky         BlueskyRecord `json:"bluesky"`
                Fediverse       FediverseStatus `json:"fediverse"`
                Visible         bool `json:"visible"`
            }
        )
        var updatedBlog UpdatedBlog

        err = json.NewDecoder(r.Body).Decode(&updatedBlog)
        if err != nil {
            fmt.Printf("WARN: Failed to update blog %s: %v\n", blog.ID, err)
            http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)
            return
        }

        blog.Title = updatedBlog.Title
        blog.PublishDate = updatedBlog.PublishDate
        blog.Description = updatedBlog.Description
        blog.Markdown = updatedBlog.Markdown
        if len(updatedBlog.Bluesky.ActorID) > 0 && len(updatedBlog.Bluesky.RecordID) > 0 {
            blog.Bluesky = &model.BlueskyRecord{
                ActorDID: updatedBlog.Bluesky.ActorID,
                RecordID: updatedBlog.Bluesky.RecordID,
            }
        } else {
            blog.Bluesky = nil
        }
        if len(updatedBlog.Fediverse.AccountID) > 0 && len(updatedBlog.Fediverse.StatusID) > 0 {
            blog.Fediverse = &model.FediverseActivity{
                AccountID: updatedBlog.Fediverse.AccountID,
                StatusID: updatedBlog.Fediverse.StatusID,
            }
        } else {
            blog.Fediverse = nil
        }
        blog.Visible = updatedBlog.Visible

        err = controller.UpdateBlogPost(app.DB, blogID, blog)
        if err != nil {
            fmt.Printf("WARN: Failed to update release %s: %v\n", blogID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
        }

        app.Log.Info(log.TYPE_BLOG, "Blog post \"%s\" updated by \"%s\".", blog.ID, session.Account.Username)

        w.Header().Add("Content-Type", "application/json")
        w.WriteHeader(http.StatusCreated)
        err = json.NewEncoder(w).Encode(blog)
        if err != nil {
            fmt.Printf("WARN: Blog post %s updated, but failed to send JSON response: %v\n", blog.ID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
        }
    })
}

func DeleteBlog(app *model.AppState) http.Handler {
    return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        session := r.Context().Value("session").(*model.Session)
        blogID := r.PathValue("id")

        blog, err := controller.GetBlogPost(app.DB, blogID)
        if err != nil {
            fmt.Printf("WARN: Failed to fetch blog post %s: %v\n", blogID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }
        if blog == nil {
            http.NotFound(w, r)
            return
        }

        err = controller.DeleteBlogPost(app.DB, blogID)
        if err != nil {
            fmt.Printf("WARN: Failed to delete blog post %s: %v\n", blogID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
            return
        }

        app.Log.Info(log.TYPE_BLOG, "Blog post \"%s\" deleted by \"%s\".", blogID, session.Account.Username)

        w.Header().Add("Content-Type", "application/json")
        w.WriteHeader(http.StatusCreated)
        err = json.NewEncoder(w).Encode(blog)
        if err != nil {
            fmt.Printf("WARN: Blog post %s deleted, but failed to send JSON response: %v\n", blog.ID, err)
            http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
        }
    })
}