"""Tests for target_revenue.effort_calculator (WP-0010-T02).

Pure/offline: builds throwaway git repos and directory fixtures under
tmp_path rather than depending on any real repo's current state, so
these tests stay deterministic regardless of what target-revenue's own
history looks like later.
"""

from __future__ import annotations

import subprocess
from pathlib import Path

import pytest

from target_revenue import effort_calculator as ec


def _git(repo: Path, *args: str, env: dict | None = None) -> None:
    subprocess.run(["git", "-C", str(repo), *args], check=True, capture_output=True, env=env)


def _commit(repo: Path, message: str, epoch_seconds: int) -> None:
    (repo / "file.txt").write_text(message)
    _git(repo, "add", "file.txt")
    date = f"{epoch_seconds} +0000"
    env = {
        "GIT_AUTHOR_DATE": date,
        "GIT_COMMITTER_DATE": date,
        "GIT_AUTHOR_NAME": "test",
        "GIT_AUTHOR_EMAIL": "test@example.com",
        "GIT_COMMITTER_NAME": "test",
        "GIT_COMMITTER_EMAIL": "test@example.com",
    }
    import os

    full_env = {**os.environ, **env}
    _git(repo, "commit", "-q", "-m", message, env=full_env)


@pytest.fixture()
def git_repo(tmp_path):
    repo = tmp_path / "repo"
    repo.mkdir()
    _git(repo, "init", "-q", "-b", "main")
    return repo


# --- cluster_commit_hours ----------------------------------------------


def test_cluster_commit_hours_empty_repo_no_commits(git_repo):
    result = ec.cluster_commit_hours(git_repo)
    assert result == ec.CommitTimeEstimate(raw_hours=0.0, session_count=0, commit_count=0)


def test_cluster_commit_hours_single_commit_uses_floor(git_repo):
    _commit(git_repo, "init", 1_000_000_000)
    result = ec.cluster_commit_hours(git_repo)
    assert result.commit_count == 1
    assert result.session_count == 1
    assert result.raw_hours == pytest.approx(ec.SINGLE_COMMIT_SESSION_MINUTES / 60)


def test_cluster_commit_hours_one_session_spans_actual_time(git_repo):
    base = 1_000_000_000
    _commit(git_repo, "c1", base)
    _commit(git_repo, "c2", base + 3600)  # 1 hour later, same session
    result = ec.cluster_commit_hours(git_repo, session_gap_hours=2.0)
    assert result.session_count == 1
    assert result.commit_count == 2
    assert result.raw_hours == pytest.approx(1.0)


def test_cluster_commit_hours_gap_splits_into_two_sessions(git_repo):
    base = 1_000_000_000
    _commit(git_repo, "c1", base)
    _commit(git_repo, "c2", base + 3 * 3600)  # 3 hours later, gap > 2h default
    result = ec.cluster_commit_hours(git_repo, session_gap_hours=2.0)
    assert result.session_count == 2
    assert result.commit_count == 2
    # Both are single-commit sessions -> two floor contributions.
    assert result.raw_hours == pytest.approx(2 * ec.SINGLE_COMMIT_SESSION_MINUTES / 60)


# --- workplan_task_counts ------------------------------------------------


def test_workplan_task_counts_scans_archived_subdirectory(tmp_path):
    archived = tmp_path / "workplans" / "archived"
    archived.mkdir(parents=True)
    (archived / "old-finished.md").write_text(
        """---
id: OLD-0001
status: finished
---

```task
id: OLD-0001-T01
status: done
```
"""
    )
    result = ec.workplan_task_counts(tmp_path)
    assert result.finished_workplans == 1
    assert result.total_tasks == 1
    assert result.finished_tasks == 1


def test_workplan_task_counts_no_workplans_dir(tmp_path):
    result = ec.workplan_task_counts(tmp_path)
    assert result == ec.WorkplanTaskCounts(0, 0, 0)


def test_workplan_task_counts_counts_finished_workplans_and_tasks(tmp_path):
    workplans = tmp_path / "workplans"
    workplans.mkdir()
    (workplans / "WP-0001.md").write_text(
        """---
id: WP-0001
status: finished
---

```task
id: WP-0001-T01
status: done
```

```task
id: WP-0001-T02
status: todo
```
"""
    )
    (workplans / "WP-0002.md").write_text(
        """---
id: WP-0002
status: active
---

```task
id: WP-0002-T01
status: done
```
"""
    )
    result = ec.workplan_task_counts(tmp_path)
    assert result.finished_workplans == 1
    assert result.total_tasks == 3
    assert result.finished_tasks == 2


# --- repo_size_metrics ----------------------------------------------------


def test_repo_size_metrics_counts_files_and_lines(tmp_path):
    (tmp_path / "a.py").write_text("line1\nline2\nline3\n")
    (tmp_path / "b.py").write_text("line1\n")
    result = ec.repo_size_metrics(tmp_path)
    assert result.file_count == 2
    assert result.line_count == 4


def test_repo_size_metrics_excludes_vendored_paths(tmp_path):
    (tmp_path / "a.py").write_text("line1\n")
    vendored = tmp_path / "node_modules" / "pkg"
    vendored.mkdir(parents=True)
    (vendored / "big.js").write_text("x\n" * 1000)
    result = ec.repo_size_metrics(tmp_path)
    assert result.file_count == 1
    assert result.line_count == 1


# --- token_cost_usd --------------------------------------------------------


def test_token_cost_usd_default_pricing():
    cost = ec.token_cost_usd(1_000_000, 1_000_000)
    expected = 1_000_000 * 3e-6 + 1_000_000 * 15e-6
    assert cost == pytest.approx(expected)


def test_token_cost_usd_unknown_model_falls_back_to_default():
    cost_unknown = ec.token_cost_usd(1000, 1000, model="some-unlisted-model")
    cost_default = ec.token_cost_usd(1000, 1000, model="default")
    assert cost_unknown == cost_default


# --- estimate_target_basis: the 1-day floor and warning -------------------


def test_low_raw_estimate_triggers_floor_and_warning():
    commit_time = ec.CommitTimeEstimate(raw_hours=0.5, session_count=1, commit_count=1)
    result = ec.estimate_target_basis(
        commit_time=commit_time,
        workplan_tasks=ec.WorkplanTaskCounts(0, 0, 0),
        repo_size=ec.RepoSizeMetrics(1, 10),
        token_cost=ec.TokenCost(0, 0, 0.0),
        daily_rate=1000.0,
    )
    assert result.estimated_effort_days == ec.MANUAL_EFFORT_FLOOR_DAYS
    assert any("floor" in w.lower() for w in result.warnings)
    assert any("manual override" in w.lower() for w in result.warnings)
    assert result.derivation["raw_commit_clustered_days"] < ec.MANUAL_EFFORT_FLOOR_DAYS


def test_sufficient_raw_estimate_no_floor_warning():
    commit_time = ec.CommitTimeEstimate(
        raw_hours=ec.DEFAULT_HOURS_PER_DAY * 5, session_count=5, commit_count=20
    )
    result = ec.estimate_target_basis(
        commit_time=commit_time,
        workplan_tasks=ec.WorkplanTaskCounts(0, 0, 0),
        repo_size=ec.RepoSizeMetrics(10, 500),
        token_cost=ec.TokenCost(0, 0, 0.0),
        daily_rate=1000.0,
    )
    assert result.estimated_effort_days == pytest.approx(5.0)
    assert not any("floor" in w.lower() for w in result.warnings)


def test_high_workplan_volume_with_low_time_triggers_sanity_warning():
    commit_time = ec.CommitTimeEstimate(raw_hours=4.0, session_count=1, commit_count=2)
    result = ec.estimate_target_basis(
        commit_time=commit_time,
        workplan_tasks=ec.WorkplanTaskCounts(finished_workplans=10, total_tasks=50, finished_tasks=40),
        repo_size=ec.RepoSizeMetrics(200, 20000),
        token_cost=ec.TokenCost(0, 0, 0.0),
        daily_rate=1000.0,
    )
    assert any("under-counted" in w.lower() for w in result.warnings)


def test_derivation_shows_its_work():
    commit_time = ec.CommitTimeEstimate(raw_hours=16.0, session_count=2, commit_count=10)
    result = ec.estimate_target_basis(
        commit_time=commit_time,
        workplan_tasks=ec.WorkplanTaskCounts(2, 5, 3),
        repo_size=ec.RepoSizeMetrics(50, 3000),
        token_cost=ec.TokenCost(tokens_in=100, tokens_out=200, usd=1.23),
        daily_rate=800.0,
    )
    assert result.derivation["commits"] == 10
    assert result.derivation["sessions"] == 2
    assert result.derivation["finished_workplans"] == 2
    assert result.derivation["file_count"] == 50
    assert result.derivation["line_count"] == 3000
    assert result.derivation["tokens_in"] == 100
    assert result.approved_direct_costs == 1.23
    assert result.daily_rate == 800.0


# --- calculate_target_basis: end-to-end -----------------------------------


def test_calculate_target_basis_end_to_end(git_repo):
    base = 1_000_000_000
    _commit(git_repo, "c1", base)
    _commit(git_repo, "c2", base + ec.DEFAULT_HOURS_PER_DAY * 3 * 3600)
    result = ec.calculate_target_basis(
        git_repo, daily_rate=1000.0, tokens_in=1000, tokens_out=1000
    )
    assert result.daily_rate == 1000.0
    assert result.approved_direct_costs == pytest.approx(
        ec.token_cost_usd(1000, 1000), abs=0.01
    )
    assert isinstance(result.estimated_effort_days, float)


# --- since/until date-range scoping ---------------------------------------


def test_cluster_commit_hours_since_until_excludes_outside_window(git_repo):
    _commit(git_repo, "outside-early", 1_577_836_800)  # 2020-01-01
    _commit(git_repo, "inside", 1_614_556_800)  # 2021-03-01
    _commit(git_repo, "outside-late", 1_672_531_200)  # 2023-01-01
    result = ec.cluster_commit_hours(git_repo, since="2021-01-01", until="2021-06-01")
    assert result.commit_count == 1


def test_workplan_task_counts_since_until_filters_by_updated_date(tmp_path):
    workplans = tmp_path / "workplans"
    workplans.mkdir()
    (workplans / "old.md").write_text(
        """---
id: OLD-0001
status: finished
updated: "2020-01-01"
---

```task
id: OLD-0001-T01
status: done
```
"""
    )
    (workplans / "recent.md").write_text(
        """---
id: NEW-0001
status: finished
updated: "2026-03-03"
---

```task
id: NEW-0001-T01
status: done
```
"""
    )
    result = ec.workplan_task_counts(tmp_path, since="2026-01-01", until="2026-06-01")
    assert result.finished_workplans == 1
    assert result.total_tasks == 1


def test_workplan_task_counts_no_date_field_always_counted(tmp_path):
    workplans = tmp_path / "workplans"
    workplans.mkdir()
    (workplans / "undated.md").write_text(
        """---
id: UND-0001
status: finished
---

```task
id: UND-0001-T01
status: done
```
"""
    )
    result = ec.workplan_task_counts(tmp_path, since="2026-01-01", until="2026-06-01")
    assert result.finished_workplans == 1
    assert result.total_tasks == 1


def test_calculate_target_basis_threads_since_until(git_repo):
    base = 1_577_836_800  # 2020-01-01
    _commit(git_repo, "outside", base)
    _commit(git_repo, "inside", base + 86400 * 400)  # ~2021-02-04
    result = ec.calculate_target_basis(
        git_repo, daily_rate=1000.0, since="2021-01-01", until="2021-06-01"
    )
    assert result.derivation["commits"] == 1