package proc

import (
	"github.com/kylelemons/godebug/pretty"
	common "github.com/ncabatoff/process-exporter"
	. "gopkg.in/check.v1"
	"time"
)

type namer map[string]struct{}

func newNamer(names ...string) namer {
	nr := make(namer, len(names))
	for _, name := range names {
		nr[name] = struct{}{}
	}
	return nr
}

func (n namer) MatchAndName(nacl common.NameAndCmdline) (bool, string) {
	if _, ok := n[nacl.Name]; ok {
		return true, nacl.Name
	}
	return false, ""
}

// Test core group() functionality, i.e things not related to namers or parents
// or processes that have exited.
func (s MySuite) TestGrouperBasic(c *C) {
	newProc := func(pid int, name string, m ProcMetrics) ProcIdInfo {
		pis := newProcIdStatic(pid, 0, 0, name, nil)
		return ProcIdInfo{
			ProcId:      pis.ProcId,
			ProcStatic:  pis.ProcStatic,
			ProcMetrics: m,
		}
	}
	gr := NewGrouper(false, newNamer("g1", "g2"))
	p1 := newProc(1, "g1", ProcMetrics{1, 2, 3, 4, 5, 4, 400})
	p2 := newProc(2, "g2", ProcMetrics{2, 3, 4, 5, 6, 40, 400})
	p3 := newProc(3, "g3", ProcMetrics{})

	_, err := gr.Update(procInfoIter(p1, p2, p3))
	c.Assert(err, IsNil)

	got1 := gr.groups()
	want1 := GroupCountMap{
		"g1": GroupCounts{Counts{0, 0, 0}, 1, 4, 5, time.Time{}, 4, 0.01},
		"g2": GroupCounts{Counts{0, 0, 0}, 1, 5, 6, time.Time{}, 40, 0.1},
	}
	c.Check(got1, DeepEquals, want1, Commentf("diff %s", pretty.Compare(got1, want1)))

	// Now increment counts and memory and make sure group counts updated.
	p1.ProcMetrics = ProcMetrics{2, 3, 4, 5, 6, 4, 400}
	p2.ProcMetrics = ProcMetrics{4, 5, 6, 7, 8, 40, 400}

	_, err = gr.Update(procInfoIter(p1, p2, p3))
	c.Assert(err, IsNil)

	got2 := gr.groups()
	want2 := GroupCountMap{
		"g1": GroupCounts{Counts{1, 1, 1}, 1, 5, 6, time.Time{}, 4, 0.01},
		"g2": GroupCounts{Counts{2, 2, 2}, 1, 7, 8, time.Time{}, 40, 0.1},
	}
	c.Check(got2, DeepEquals, want2, Commentf("diff %s", pretty.Compare(got2, want2)))

	// Now add a new proc and update p2's metrics.  The
	// counts for p4 won't be factored into the total yet
	// because we only add to counts starting with the
	// second time we see a proc.  Memory and FDs are affected
	// though.
	p4 := newProc(4, "g2", ProcMetrics{1, 1, 1, 1, 1, 80, 400})
	p2.ProcMetrics = ProcMetrics{5, 6, 7, 8, 9, 40, 400}

	_, err = gr.Update(procInfoIter(p1, p2, p3, p4))
	c.Assert(err, IsNil)

	got3 := gr.groups()
	want3 := GroupCountMap{
		"g1": GroupCounts{Counts{0, 0, 0}, 1, 5, 6, time.Time{}, 4, 0.01},
		"g2": GroupCounts{Counts{1, 1, 1}, 2, 9, 10, time.Time{}, 120, 0.2},
	}
	c.Check(got3, DeepEquals, want3, Commentf("diff %s", pretty.Compare(got3, want3)))

	p4.ProcMetrics = ProcMetrics{2, 2, 2, 2, 2, 100, 400}
	p2.ProcMetrics = ProcMetrics{6, 7, 8, 8, 9, 40, 400}

	_, err = gr.Update(procInfoIter(p1, p2, p3, p4))
	c.Assert(err, IsNil)

	got4 := gr.groups()
	want4 := GroupCountMap{
		"g1": GroupCounts{Counts{0, 0, 0}, 1, 5, 6, time.Time{}, 4, 0.01},
		"g2": GroupCounts{Counts{2, 2, 2}, 2, 10, 11, time.Time{}, 140, 0.25},
	}
	c.Check(got4, DeepEquals, want4, Commentf("diff %s", pretty.Compare(got4, want4)))

}

// Test that if a proc is tracked, we track its descendants, and if not as
// before it gets ignored.  We won't bother testing metric accumulation since
// that should be covered by TestGrouperBasic.
func (s MySuite) TestGrouperParents(c *C) {
	newProc := func(pid, ppid int, name string) ProcIdInfo {
		pis := newProcIdStatic(pid, ppid, 0, name, nil)
		return ProcIdInfo{
			ProcId:      pis.ProcId,
			ProcStatic:  pis.ProcStatic,
			ProcMetrics: ProcMetrics{},
		}
	}
	gr := NewGrouper(true, newNamer("g1", "g2"))
	p1 := newProc(1, 0, "g1")
	p2 := newProc(2, 0, "g2")
	p3 := newProc(3, 0, "g3")

	_, err := gr.Update(procInfoIter(p1, p2, p3))
	c.Assert(err, IsNil)

	got1 := gr.groups()
	want1 := GroupCountMap{
		"g1": GroupCounts{Counts{}, 1, 0, 0, time.Time{}, 0, 0},
		"g2": GroupCounts{Counts{}, 1, 0, 0, time.Time{}, 0, 0},
	}
	c.Check(got1, DeepEquals, want1, Commentf("diff %s", pretty.Compare(got1, want1)))

	// Now we'll give each of the procs a child and test that the count of procs
	// in each group is incremented.

	p4 := newProc(4, p1.Pid, "")
	p5 := newProc(5, p2.Pid, "")
	p6 := newProc(6, p3.Pid, "")

	_, err = gr.Update(procInfoIter(p1, p2, p3, p4, p5, p6))
	c.Assert(err, IsNil)

	got2 := gr.groups()
	want2 := GroupCountMap{
		"g1": GroupCounts{Counts{}, 2, 0, 0, time.Time{}, 0, 0},
		"g2": GroupCounts{Counts{}, 2, 0, 0, time.Time{}, 0, 0},
	}
	c.Check(got2, DeepEquals, want2, Commentf("diff %s", pretty.Compare(got2, want2)))

	// Now we'll let p4 die, and give p5 a child and grandchild and great-grandchild.

	p7 := newProc(7, p5.Pid, "")
	p8 := newProc(8, p7.Pid, "")
	p9 := newProc(9, p8.Pid, "")

	_, err = gr.Update(procInfoIter(p1, p2, p3, p5, p6, p7, p8, p9))
	c.Assert(err, IsNil)

	got3 := gr.groups()
	want3 := GroupCountMap{
		"g1": GroupCounts{Counts{}, 1, 0, 0, time.Time{}, 0, 0},
		"g2": GroupCounts{Counts{}, 5, 0, 0, time.Time{}, 0, 0},
	}
	c.Check(got3, DeepEquals, want3, Commentf("diff %s", pretty.Compare(got3, want3)))
}

// Test that Groups() reports on new CPU/IO activity, even if some processes in the
// group have gone away.
func (s MySuite) TestGrouperGroup(c *C) {
	newProc := func(pid int, name string, m ProcMetrics) ProcIdInfo {
		pis := newProcIdStatic(pid, 0, 0, name, nil)
		return ProcIdInfo{
			ProcId:      pis.ProcId,
			ProcStatic:  pis.ProcStatic,
			ProcMetrics: m,
		}
	}
	gr := NewGrouper(false, newNamer("g1"))

	// First call should return zero CPU/IO.
	p1 := newProc(1, "g1", ProcMetrics{1, 2, 3, 4, 5, 8, 400})
	_, err := gr.Update(procInfoIter(p1))
	c.Assert(err, IsNil)
	got1 := gr.Groups()
	want1 := GroupCountMap{
		"g1": GroupCounts{Counts{0, 0, 0}, 1, 4, 5, time.Time{}, 8, 0.02},
	}
	c.Check(got1, DeepEquals, want1)

	// Second call should return the delta CPU/IO from first observance,
	// as well as latest memory/proccount.
	p1.ProcMetrics = ProcMetrics{2, 3, 4, 5, 6, 12, 400}
	_, err = gr.Update(procInfoIter(p1))
	c.Assert(err, IsNil)
	got2 := gr.Groups()
	want2 := GroupCountMap{
		"g1": GroupCounts{Counts{1, 1, 1}, 1, 5, 6, time.Time{}, 12, 0.03},
	}
	c.Check(got2, DeepEquals, want2)

	// Third call: process hasn't changed, nor should our group stats.
	_, err = gr.Update(procInfoIter(p1))
	c.Assert(err, IsNil)
	got3 := gr.Groups()
	want3 := GroupCountMap{
		"g1": GroupCounts{Counts{1, 1, 1}, 1, 5, 6, time.Time{}, 12, 0.03},
	}
	c.Check(got3, DeepEquals, want3, Commentf("diff %s", pretty.Compare(got3, want3)))
}

// Test that Groups() reports on new CPU/IO activity, even if some processes in the
// group have gone away.
func (s MySuite) TestGrouperNonDecreasing(c *C) {
	newProc := func(pid int, name string, m ProcMetrics) ProcIdInfo {
		pis := newProcIdStatic(pid, 0, 0, name, nil)
		return ProcIdInfo{
			ProcId:      pis.ProcId,
			ProcStatic:  pis.ProcStatic,
			ProcMetrics: m,
		}
	}
	gr := NewGrouper(false, newNamer("g1", "g2"))
	p1 := newProc(1, "g1", ProcMetrics{1, 2, 3, 4, 5, 4, 400})
	p2 := newProc(2, "g2", ProcMetrics{2, 3, 4, 5, 6, 40, 400})

	_, err := gr.Update(procInfoIter(p1, p2))
	c.Assert(err, IsNil)

	got1 := gr.Groups()
	want1 := GroupCountMap{
		"g1": GroupCounts{Counts{0, 0, 0}, 1, 4, 5, time.Time{}, 4, 0.01},
		"g2": GroupCounts{Counts{0, 0, 0}, 1, 5, 6, time.Time{}, 40, 0.1},
	}
	c.Check(got1, DeepEquals, want1, Commentf("diff %s", pretty.Compare(got1, want1)))

	// Now add a new proc p3 to g2, and increment p1/p2's metrics.
	p1.ProcMetrics = ProcMetrics{2, 3, 4, 5, 6, 8, 400}
	p2.ProcMetrics = ProcMetrics{4, 5, 6, 7, 8, 80, 400}
	p3 := newProc(3, "g2", ProcMetrics{1, 1, 1, 1, 1, 8, 400})
	_, err = gr.Update(procInfoIter(p1, p2, p3))
	c.Assert(err, IsNil)

	got2 := gr.Groups()
	want2 := GroupCountMap{
		"g1": GroupCounts{Counts{1, 1, 1}, 1, 5, 6, time.Time{}, 8, 0.02},
		"g2": GroupCounts{Counts{2, 2, 2}, 2, 8, 9, time.Time{}, 88, 0.2},
	}
	c.Check(got2, DeepEquals, want2, Commentf("diff %s", pretty.Compare(got2, want2)))

	// Now update p3's metrics and kill p2.
	p3.ProcMetrics = ProcMetrics{2, 3, 4, 5, 6, 8, 400}
	_, err = gr.Update(procInfoIter(p1, p3))
	c.Assert(err, IsNil)

	got3 := gr.Groups()
	want3 := GroupCountMap{
		"g1": GroupCounts{Counts{1, 1, 1}, 1, 5, 6, time.Time{}, 8, 0.02},
		"g2": GroupCounts{Counts{3, 4, 5}, 1, 5, 6, time.Time{}, 8, 0.02},
	}
	c.Check(got3, DeepEquals, want3, Commentf("diff %s", pretty.Compare(got3, want3)))

	// Now update p3's metrics and kill p1.
	p3.ProcMetrics = ProcMetrics{4, 4, 4, 2, 1, 4, 400}
	_, err = gr.Update(procInfoIter(p3))
	c.Assert(err, IsNil)

	got4 := gr.Groups()
	want4 := GroupCountMap{
		"g1": GroupCounts{Counts{1, 1, 1}, 0, 0, 0, time.Time{}, 0, 0},
		"g2": GroupCounts{Counts{5, 5, 5}, 1, 2, 1, time.Time{}, 4, 0.01},
	}
	c.Check(got4, DeepEquals, want4, Commentf("diff %s\n%s", pretty.Compare(got4, want4), pretty.Sprint(gr)))

}