From 609c2ed8ac7e710d8d6666102ceb3230ec746a88 Mon Sep 17 00:00:00 2001
From: Meutel <meutel@meutel.net>
Date: Fri, 30 Dec 2016 15:40:21 +0100
Subject: [PATCH] Book authors

---
 db.c     | 64 +++++++++++++++++++++++++++++++++++++++++++++++++-------
 extern.h |  2 +-
 main.c   | 33 ++++++++++++++++++++++++-----
 3 files changed, 86 insertions(+), 13 deletions(-)

diff --git a/db.c b/db.c
index 89290c3..10978fb 100644
--- a/db.c
+++ b/db.c
@@ -31,14 +31,26 @@
 enum    stmt {
   STMT_BOOK,
   STMT_BOOKS,
+  STMT_BOOKS_AUTHORS,
   STMT__MAX
 };
 
 static const char *const stmts[STMT__MAX] = {
   /* STMT_BOOK */
   "SELECT books.id AS id,title,series_index,name as series_name,series.id AS series_id FROM books LEFT OUTER JOIN books_series_link ON books.id = books_series_link.book LEFT OUTER JOIN series ON series.id = books_series_link.series WHERE books.id = ?",
-  /* STMT_BOOKS */
-  "SELECT books.id AS id,title,series_index,name as series_name,series.id AS series_id FROM books LEFT OUTER JOIN books_series_link ON books.id = books_series_link.book LEFT OUTER JOIN series ON series.id = books_series_link.series LIMIT ?",
+  /* STMT_BOOKS */ //TODO offset
+  "SELECT books.id AS id,title,series_index,name as series_name,series.id AS series_id FROM books LEFT OUTER JOIN books_series_link ON books.id = books_series_link.book LEFT OUTER JOIN series ON series.id = books_series_link.series ORDER BY id LIMIT ?",
+  /* STMT_BOOKS_AUTHORS */
+  "SELECT authors.id, authors.name, books_authors_link.book as book FROM authors, books_authors_link WHERE books_authors_link.author = authors.id AND books_authors_link.book IN ( SELECT id FROM books ORDER BY id LIMIT ? )",
+};
+
+/*
+ * Linked list authors of book.
+ */
+struct bookauth {
+  Author *a;
+  BookAdv *b;
+  struct bookauth *p;
 };
 
 static void
@@ -101,18 +113,56 @@ db_books_load(struct kreq *r, BookAdv **books, int limit)
     return 0;
   }
   struct ksqlstmt *stmt;
-  int i = 0;
+  struct bookauth *p = NULL;
+  int i, count = 0;
+
   ksql_stmt_alloc(r->arg, &stmt, 
             stmts[STMT_BOOKS], 
             STMT_BOOKS);
   ksql_bind_int(stmt, 0, limit);
   while (KSQL_ROW == ksql_stmt_step(stmt)) {
-    books[i] = kcalloc(1, sizeof(BookAdv));
-    db_book_fill(&books[i]->b,stmt);
-    i++;
+    books[count] = kcalloc(1, sizeof(BookAdv));
+    db_book_fill(&books[count]->b,stmt);
+    books[count]->asize = 0;
+    count++;
   }
   ksql_stmt_free(stmt);
-  return i;
+
+  ksql_stmt_alloc(r->arg, &stmt, 
+            stmts[STMT_BOOKS_AUTHORS], 
+            STMT_BOOKS_AUTHORS);
+  ksql_bind_int(stmt, 0, limit);
+  while (KSQL_ROW == ksql_stmt_step(stmt)) {
+    // add author to list, link related book and increment asize
+    struct bookauth *item = kcalloc(1, sizeof(struct bookauth));
+    item->a = kcalloc(1, sizeof(Author));
+    item->a->id = ksql_stmt_int(stmt, 0);
+    item->a->name = kstrdup(ksql_stmt_str(stmt, 1));
+    int64_t bid = ksql_stmt_int(stmt, 2);
+    for (i = 0; i < count && NULL == item->b; i++) {
+      if (books[i]->b.id == bid) {
+        item->b = books[i];
+        item->b->asize++;
+      }
+    }
+    item->p = p;
+    p = item;
+  }
+
+  // assign authors to books
+  while (NULL != p) {
+    if (NULL != p->b && NULL == p->b->a && p->b->asize > 0) {
+      p->b->a = kcalloc(p->b->asize, sizeof(Author));
+      p->b->asize = 0; // use as counter for insert
+    }
+    p->b->a[p->b->asize] = p->a;// add author
+    p->b->asize++;
+    p = p->p;
+  }
+  // TODO free linked list (not authors)
+  ksql_stmt_free(stmt);
+
+  return count;
 }
 
 Book *
diff --git a/extern.h b/extern.h
index d028ed0..b5a4d55 100644
--- a/extern.h
+++ b/extern.h
@@ -52,7 +52,7 @@ typedef struct
 typedef struct
 {
   Book b;
-  Author *a;
+  Author **a;
   size_t asize;
   // TODO tags
 } BookAdv;
diff --git a/main.c b/main.c
index a59bd04..34ec26c 100644
--- a/main.c
+++ b/main.c
@@ -86,7 +86,7 @@ http_open(struct kreq *r, enum khttp code)
 	khttp_body(r);
 }
 
-void
+static void
 puterror(struct kjsonreq *req, char *message)
 {
   kjson_obj_open(req);
@@ -94,7 +94,21 @@ puterror(struct kjsonreq *req, char *message)
   kjson_obj_close(req);
 }
 
-void
+/*
+ * Append author object to json (NOT CLOSED).
+ */
+static void
+putauthor(struct kjsonreq *req, Author *a)
+{
+  kjson_obj_open(req);
+  kjson_putintp(req, "id", a->id);
+  kjson_putstringp(req, "name", a->name);
+}
+
+/*
+ * Append book object to json (NOT CLOSED).
+ */
+static void
 putbook(struct kjsonreq *req, Book *b)
 {
   kjson_obj_open(req);
@@ -107,7 +121,6 @@ putbook(struct kjsonreq *req, Book *b)
     kjson_putdoublep(req, "idx", b->s_idx);
     kjson_obj_close(req);
   }
-  kjson_obj_close(req);
 }
 
 static void
@@ -132,14 +145,24 @@ sendbooks(struct kreq *r)
     puterror(&req, "Unknown book");
   } else if (NULL != b) {
     putbook(&req, b);
+    kjson_obj_close(&req);
     db_book_free(b);
   } else {
     kjson_array_open(&req);
-    BookAdv **books = kcalloc(10, sizeof(BookAdv));
-    res = db_books_load(r, books, 10);
+    BookAdv **books = kcalloc(200, sizeof(BookAdv));
+    res = db_books_load(r, books, 200);
     while (i < res) {
       Book b = books[i]->b;
       putbook(&req, &b);
+      if (books[i]->asize > 0) {
+        kjson_arrayp_open(&req, "authors");
+        for (size_t j=0; j<books[i]->asize; j++) {
+          putauthor(&req, books[i]->a[j]);
+          kjson_obj_close(&req);
+        }
+        kjson_array_close(&req);
+      }
+      kjson_obj_close(&req);
       db_book_adv_free(books[i]);
       i++;
     }