1 files changed, 77 insertions, 0 deletions
diff --git a/lib/bisect.nim b/lib/bisect.nim
new file mode 100644
index 0000000..53d73f1
--- /dev/null
+++ b/lib/bisect.nim
@@ -0,0 +1,77 @@
+import future, os, osproc, re, strutils
+
+{.passL: "-lalpm".}
+
+proc vercmp(a: cstring, b: cstring): cint
+  {.cdecl, importc: "alpm_pkg_vercmp".}
+
+proc getSourceVersion(relativePath: string): seq[string] =
+  let lines = execProcess("/bin/bash", ["-c",
+    """source "$1/PKGBUILD" && echo "$epoch" && echo "$pkgver" && echo "$pkgrel"""",
+    "bash", relativePath], options = {}).split("\n")
+  if lines.len == 4:
+    lines[0 .. 2]
+  else:
+    @[]
+
+proc getSrcInfoVersion(relativePath: string): seq[string] =
+  var file: File
+  var epoch = ""
+  var pkgver = ""
+  var pkgrel = ""
+
+  if file.open(relativePath & "/.SRCINFO"):
+    try:
+      var matches: array[2, string]
+      while true:
+        let line = file.readLine()
+        if line.match(re"[\t\ ]*(\w+)\ =\ (.*)", matches):
+          case matches[0]:
+            of "epoch":
+              epoch = matches[1]
+            of "pkgver":
+              pkgver = matches[1]
+            of "pkgrel":
+              pkgrel = matches[1]
+            else:
+              discard
+    except:
+      discard
+    finally:
+      file.close()
+
+  @[epoch, pkgver, pkgrel]
+
+let compareMethod = commandLineParams()[0]
+let relativePath = commandLineParams()[1]
+let compareVersion = commandLineParams()[2]
+
+let (currentVersion, supported) = if compareMethod == "source":
+    (getSourceVersion(relativePath), true)
+  elif compareMethod == "srcinfo":
+    (getSrcInfoVersion(relativePath), true)
+  else:
+    (@[], false)
+
+if not supported:
+  programResult = 255
+elif currentVersion.len != 3:
+  programResult = 125
+else:
+  let epoch = currentVersion[0].strip
+  let pkgver = currentVersion[1].strip
+  let pkgrel = currentVersion[2].strip
+
+  if pkgver.len == 0 or pkgrel.len == 0:
+    programResult = 125
+  else:
+    let version = if epoch.len > 0:
+        epoch & ":" & pkgver & "-" & pkgrel
+      else:
+        pkgver & "-" & pkgrel
+
+    echo(version)
+    if vercmp(compareVersion, version) > 0:
+      programResult = 0
+    else:
+      programResult = 1