use super::harness::*;
#[allow(unused_imports)]
use super::harness::{forth_with_counter, new_emission_counter};
use std::collections::HashMap;

fn parse_params(output: &str) -> HashMap<String, f64> {
    let mut params = HashMap::new();
    let parts: Vec<&str> = output.trim_start_matches('/').split('/').collect();
    let mut i = 0;
    while i + 1 < parts.len() {
        if let Ok(v) = parts[i + 1].parse::<f64>() {
            params.insert(parts[i].to_string(), v);
        }
        i += 2;
    }
    params
}

fn get_deltas(outputs: &[String]) -> Vec<f64> {
    outputs
        .iter()
        .map(|o| parse_params(o).get("delta").copied().unwrap_or(0.0))
        .collect()
}

fn get_durs(outputs: &[String]) -> Vec<f64> {
    outputs
        .iter()
        .map(|o| parse_params(o).get("dur").copied().unwrap_or(0.0))
        .collect()
}

fn get_sounds(outputs: &[String]) -> Vec<String> {
    outputs
        .iter()
        .map(|o| {
            let parts: Vec<&str> = o.trim_start_matches('/').split('/').collect();
            if parts.len() >= 2 && parts[0] == "sound" {
                parts[1].to_string()
            } else {
                String::new()
            }
        })
        .collect()
}

const EPSILON: f64 = 1e-9;

fn approx_eq(a: f64, b: f64) -> bool {
    (a - b).abs() < EPSILON
}

// At 120 BPM, speed 1.0: stepdur = 60/120/4/1 = 0.125s
// Root duration = 4 * stepdur = 0.5s

#[test]
fn stepdur_baseline() {
    let f = run("stepdur");
    assert!(approx_eq(stack_float(&f), 0.125));
}

#[test]
fn single_emit() {
    let outputs = expect_outputs(r#""kick" s @"#, 1);
    let deltas = get_deltas(&outputs);
    assert!(approx_eq(deltas[0], 0.0), "single emit at start should have delta 0");
}

#[test]
fn implicit_subdivision_2() {
    let outputs = expect_outputs(r#""kick" s @ @"#, 2);
    let deltas = get_deltas(&outputs);
    let step = 0.5 / 2.0;
    assert!(approx_eq(deltas[0], 0.0), "first slot at 0");
    assert!(approx_eq(deltas[1], step), "second slot at {}, got {}", step, deltas[1]);
}

#[test]
fn implicit_subdivision_4() {
    let outputs = expect_outputs(r#""kick" s @ @ @ @"#, 4);
    let deltas = get_deltas(&outputs);
    let step = 0.5 / 4.0;
    for (i, delta) in deltas.iter().enumerate() {
        let expected = step * i as f64;
        assert!(
            approx_eq(*delta, expected),
            "slot {}: expected {}, got {}",
            i, expected, delta
        );
    }
}

#[test]
fn implicit_subdivision_3() {
    let outputs = expect_outputs(r#""kick" s @ @ @"#, 3);
    let deltas = get_deltas(&outputs);
    let step = 0.5 / 3.0;
    assert!(approx_eq(deltas[0], 0.0));
    assert!(approx_eq(deltas[1], step), "got {}", deltas[1]);
    assert!(approx_eq(deltas[2], 2.0 * step), "got {}", deltas[2]);
}

#[test]
fn silence_creates_gap() {
    let outputs = expect_outputs(r#""kick" s @ ~ @"#, 2);
    let deltas = get_deltas(&outputs);
    let step = 0.5 / 3.0;
    assert!(approx_eq(deltas[0], 0.0), "first at 0");
    assert!(
        approx_eq(deltas[1], 2.0 * step),
        "third slot (after silence) at {}, got {}",
        2.0 * step,
        deltas[1]
    );
}

#[test]
fn silence_at_start() {
    let outputs = expect_outputs(r#""kick" s ~ @"#, 1);
    let deltas = get_deltas(&outputs);
    let step = 0.5 / 2.0;
    assert!(
        approx_eq(deltas[0], step),
        "emit after silence at {}, got {}",
        step,
        deltas[0]
    );
}

#[test]
fn silence_only() {
    let outputs = expect_outputs(r#""kick" s ~"#, 0);
    assert!(outputs.is_empty(), "silence only should produce no output");
}

#[test]
fn sound_persists() {
    let outputs = expect_outputs(r#""kick" s @ @ "hat" s @ @"#, 4);
    let sounds = get_sounds(&outputs);
    assert_eq!(sounds[0], "kick");
    assert_eq!(sounds[1], "kick");
    assert_eq!(sounds[2], "hat");
    assert_eq!(sounds[3], "hat");
}

#[test]
fn alternating_sounds() {
    let outputs = expect_outputs(r#""kick" s @ "snare" s @ "kick" s @ "snare" s @"#, 4);
    let sounds = get_sounds(&outputs);
    assert_eq!(sounds, vec!["kick", "snare", "kick", "snare"]);
}

#[test]
fn dur_matches_slot_duration() {
    let outputs = expect_outputs(r#""kick" s @ @ @ @"#, 4);
    let durs = get_durs(&outputs);
    let expected_dur = 0.5 / 4.0;
    for (i, dur) in durs.iter().enumerate() {
        assert!(
            approx_eq(*dur, expected_dur),
            "slot {} dur: expected {}, got {}",
            i, expected_dur, dur
        );
    }
}

#[test]
fn tempo_affects_subdivision() {
    let ctx = ctx_with(|c| c.tempo = 60.0);
    let f = forth();
    let outputs = f.evaluate(r#""kick" s @ @"#, &ctx).unwrap();
    let deltas = get_deltas(&outputs);
    // At 60 BPM: stepdur = 0.25, root dur = 1.0
    let step = 1.0 / 2.0;
    assert!(approx_eq(deltas[0], 0.0));
    assert!(approx_eq(deltas[1], step), "got {}", deltas[1]);
}

#[test]
fn speed_affects_subdivision() {
    let ctx = ctx_with(|c| c.speed = 2.0);
    let f = forth();
    let outputs = f.evaluate(r#""kick" s @ @"#, &ctx).unwrap();
    let deltas = get_deltas(&outputs);
    // At speed 2.0: stepdur = 0.0625, root dur = 0.25
    let step = 0.25 / 2.0;
    assert!(approx_eq(deltas[0], 0.0));
    assert!(approx_eq(deltas[1], step), "got {}", deltas[1]);
}

#[test]
fn cycle_picks_by_step() {
    for runs in 0..4 {
        let ctx = ctx_with(|c| c.runs = runs);
        let f = forth();
        let outputs = f.evaluate(r#""kick" s < @ ~ >"#, &ctx).unwrap();
        if runs % 2 == 0 {
            assert_eq!(outputs.len(), 1, "runs={}: @ should be picked", runs);
        } else {
            assert_eq!(outputs.len(), 0, "runs={}: ~ should be picked", runs);
        }
    }
}

#[test]
fn pcycle_picks_by_pattern() {
    for iter in 0..4 {
        let ctx = ctx_with(|c| c.iter = iter);
        let f = forth();
        let outputs = f.evaluate(r#""kick" s << @ ~ >>"#, &ctx).unwrap();
        if iter % 2 == 0 {
            assert_eq!(outputs.len(), 1, "iter={}: @ should be picked", iter);
        } else {
            assert_eq!(outputs.len(), 0, "iter={}: ~ should be picked", iter);
        }
    }
}

#[test]
fn cycle_with_sounds() {
    for runs in 0..3 {
        let ctx = ctx_with(|c| c.runs = runs);
        let f = forth();
        let outputs = f.evaluate(r#"< { "kick" s @ } { "hat" s @ } { "snare" s @ } >"#, &ctx).unwrap();
        assert_eq!(outputs.len(), 1, "runs={}: expected 1 output", runs);
        let sounds = get_sounds(&outputs);
        let expected = ["kick", "hat", "snare"][runs % 3];
        assert_eq!(sounds[0], expected, "runs={}: expected {}", runs, expected);
    }
}

#[test]
fn dot_alias_for_emit() {
    let outputs = expect_outputs(r#""kick" s . . . ."#, 4);
    let sounds = get_sounds(&outputs);
    assert_eq!(sounds, vec!["kick", "kick", "kick", "kick"]);
}

#[test]
fn dot_with_silence() {
    let outputs = expect_outputs(r#""kick" s . ~ . ~"#, 2);
    let deltas = get_deltas(&outputs);
    let step = 0.5 / 4.0;
    assert!(approx_eq(deltas[0], 0.0));
    assert!(approx_eq(deltas[1], 2.0 * step));
}

#[test]
fn internal_alternation_basic() {
    let outputs = expect_outputs(r#"| "kick" "snare" | s . . . ."#, 4);
    let sounds = get_sounds(&outputs);
    assert_eq!(sounds, vec!["kick", "snare", "kick", "snare"]);
}

#[test]
fn internal_alternation_three_sounds() {
    let outputs = expect_outputs(r#"| "kick" "snare" "hat" | s . . . . . ."#, 6);
    let sounds = get_sounds(&outputs);
    assert_eq!(sounds, vec!["kick", "snare", "hat", "kick", "snare", "hat"]);
}

#[test]
fn internal_alternation_single_item() {
    let outputs = expect_outputs(r#"| "kick" | s . . . ."#, 4);
    let sounds = get_sounds(&outputs);
    assert_eq!(sounds, vec!["kick", "kick", "kick", "kick"]);
}

#[test]
fn internal_alternation_with_params() {
    let outputs = expect_outputs(r#"| 0.5 0.9 | gain "kick" s . ."#, 2);
    fn parse_gain(output: &str) -> f64 {
        let parts: Vec<&str> = output.trim_start_matches('/').split('/').collect();
        for i in 0..parts.len() - 1 {
            if parts[i] == "gain" {
                return parts[i + 1].parse().unwrap_or(0.0);
            }
        }
        0.0
    }
    let gains: Vec<f64> = outputs.iter().map(|o| parse_gain(o)).collect();
    assert!(approx_eq(gains[0], 0.5), "first gain should be 0.5, got {}", gains[0]);
    assert!(approx_eq(gains[1], 0.9), "second gain should be 0.9, got {}", gains[1]);
}

#[test]
fn internal_alternation_empty_error() {
    let f = forth();
    let result = f.evaluate(r#"| | . ."#, &default_ctx());
    assert!(result.is_err(), "empty internal cycle should error");
}

#[test]
fn div_basic_subdivision() {
    let outputs = expect_outputs(r#"div "kick" s . "hat" s . end"#, 2);
    let deltas = get_deltas(&outputs);
    let sounds = get_sounds(&outputs);
    assert_eq!(sounds, vec!["kick", "hat"]);
    assert!(approx_eq(deltas[0], 0.0));
    assert!(approx_eq(deltas[1], 0.25), "second should be at 0.25, got {}", deltas[1]);
}

#[test]
fn div_superposition() {
    let outputs = expect_outputs(r#"div "kick" s . end div "hat" s . end"#, 2);
    let deltas = get_deltas(&outputs);
    let sounds = get_sounds(&outputs);
    assert_eq!(sounds.len(), 2);
    // Both at delta 0 (superposed)
    assert!(approx_eq(deltas[0], 0.0));
    assert!(approx_eq(deltas[1], 0.0));
}

#[test]
fn div_with_root_emit() {
    // kick at root level, hat in div - both should superpose at 0
    // Note: div resolves first (when end is hit), root resolves at script end
    let outputs = expect_outputs(r#""kick" s . div "hat" s . end"#, 2);
    let deltas = get_deltas(&outputs);
    let sounds = get_sounds(&outputs);
    // Order is hat then kick because div resolves before root
    assert_eq!(sounds, vec!["hat", "kick"]);
    assert!(approx_eq(deltas[0], 0.0));
    assert!(approx_eq(deltas[1], 0.0));
}

#[test]
fn div_nested() {
    // kick takes first slot in outer div, inner div takes second slot
    // Inner div resolves first, then outer div resolves
    let outputs = expect_outputs(r#"div "kick" s . div "hat" s . . end end"#, 3);
    let sounds = get_sounds(&outputs);
    let deltas = get_deltas(&outputs);
    // Inner div resolves first (hat, hat), then outer div (kick)
    assert_eq!(sounds[0], "hat");
    assert_eq!(sounds[1], "hat");
    assert_eq!(sounds[2], "kick");
    // Inner div inherits parent's start (0) and duration (0.5), subdivides into 2
    assert!(approx_eq(deltas[0], 0.0), "first hat at 0, got {}", deltas[0]);
    assert!(approx_eq(deltas[1], 0.25), "second hat at 0.25, got {}", deltas[1]);
    // Outer div has 2 slots: kick at 0, inner div at slot 1 (but inner resolved independently)
    assert!(approx_eq(deltas[2], 0.0), "kick at 0, got {}", deltas[2]);
}

#[test]
fn div_with_silence() {
    let outputs = expect_outputs(r#"div "kick" s . ~ end"#, 1);
    let deltas = get_deltas(&outputs);
    assert!(approx_eq(deltas[0], 0.0));
}

#[test]
fn div_unmatched_end_error() {
    let f = forth();
    let result = f.evaluate(r#""kick" s . end"#, &default_ctx());
    assert!(result.is_err(), "unmatched end should error");
}

#[test]
fn alternator_with_scale() {
    let outputs = expect_outputs(r#""sine" s | 0 1 2 3 | mixolydian note . . . ."#, 4);
    fn parse_note(output: &str) -> i64 {
        let parts: Vec<&str> = output.trim_start_matches('/').split('/').collect();
        for i in 0..parts.len() - 1 {
            if parts[i] == "note" {
                return parts[i + 1].parse().unwrap_or(0);
            }
        }
        0
    }
    let notes: Vec<i64> = outputs.iter().map(|o| parse_note(o)).collect();
    // mixolydian from C4: 0->60, 1->62, 2->64, 3->65
    assert_eq!(notes, vec![60, 62, 64, 65]);
}

#[test]
fn alternator_with_arithmetic() {
    let outputs = expect_outputs(r#""sine" s | 100 200 | 2 * freq . ."#, 2);
    fn parse_freq(output: &str) -> f64 {
        let parts: Vec<&str> = output.trim_start_matches('/').split('/').collect();
        for i in 0..parts.len() - 1 {
            if parts[i] == "freq" {
                return parts[i + 1].parse().unwrap_or(0.0);
            }
        }
        0.0
    }
    let freqs: Vec<f64> = outputs.iter().map(|o| parse_freq(o)).collect();
    assert!(approx_eq(freqs[0], 200.0), "first freq: expected 200, got {}", freqs[0]);
    assert!(approx_eq(freqs[1], 400.0), "second freq: expected 400, got {}", freqs[1]);
}

#[test]
fn stack_superposes_sounds() {
    let outputs = expect_outputs(r#"stack "kick" s . "hat" s . end"#, 2);
    let deltas = get_deltas(&outputs);
    let sounds = get_sounds(&outputs);
    assert_eq!(sounds.len(), 2);
    // Both at delta 0 (stacked/superposed)
    assert!(approx_eq(deltas[0], 0.0));
    assert!(approx_eq(deltas[1], 0.0));
}

#[test]
fn stack_with_multiple_emits() {
    let outputs = expect_outputs(r#"stack "kick" s . . . . end"#, 4);
    let deltas = get_deltas(&outputs);
    // All 4 kicks at delta 0
    for (i, delta) in deltas.iter().enumerate() {
        assert!(approx_eq(*delta, 0.0), "emit {} should be at 0, got {}", i, delta);
    }
}

#[test]
fn stack_inside_div() {
    // div subdivides, stack inside superposes
    // stack doesn't claim a slot in parent div, so snare is also at 0
    let outputs = expect_outputs(r#"div stack "kick" s . "hat" s . end "snare" s . end"#, 3);
    let deltas = get_deltas(&outputs);
    let sounds = get_sounds(&outputs);
    // stack resolves first (kick, hat at 0), then div resolves (snare at 0)
    // since stack doesn't consume a slot in the parent div
    assert_eq!(sounds[0], "kick");
    assert_eq!(sounds[1], "hat");
    assert_eq!(sounds[2], "snare");
    assert!(approx_eq(deltas[0], 0.0));
    assert!(approx_eq(deltas[1], 0.0));
    assert!(approx_eq(deltas[2], 0.0), "snare at 0, got {}", deltas[2]);
}

#[test]
fn div_then_stack_sequential() {
    // Nested div doesn't claim a slot in parent, only emit/silence do
    // So nested div and snare both resolve with parent's timing
    let outputs = expect_outputs(r#"div div "kick" s . "hat" s . end "snare" s . end"#, 3);
    let deltas = get_deltas(&outputs);
    let sounds = get_sounds(&outputs);
    // Inner div resolves first (kick at 0, hat at 0.25 of parent duration)
    // Outer div has 1 slot (snare's .), so snare at 0
    assert_eq!(sounds[0], "kick");
    assert_eq!(sounds[1], "hat");
    assert_eq!(sounds[2], "snare");
    assert!(approx_eq(deltas[0], 0.0));
    assert!(approx_eq(deltas[1], 0.25), "hat at 0.25, got {}", deltas[1]);
    assert!(approx_eq(deltas[2], 0.0), "snare at 0, got {}", deltas[2]);
}

#[test]
fn emit_n_basic() {
    let outputs = expect_outputs(r#""kick" s 4 .!"#, 4);
    let sounds = get_sounds(&outputs);
    assert_eq!(sounds, vec!["kick", "kick", "kick", "kick"]);
}

#[test]
fn emit_n_with_alternator() {
    let outputs = expect_outputs(r#"| "kick" "snare" | s 4 .!"#, 4);
    let sounds = get_sounds(&outputs);
    assert_eq!(sounds, vec!["kick", "snare", "kick", "snare"]);
}

#[test]
fn emit_n_zero() {
    let outputs = expect_outputs(r#""kick" s 0 .!"#, 0);
    assert!(outputs.is_empty());
}

#[test]
fn emit_n_negative_error() {
    let f = forth();
    let result = f.evaluate(r#""kick" s -1 .!"#, &default_ctx());
    assert!(result.is_err());
}

#[test]
fn persistent_counter_across_evaluations() {
    let counter = new_emission_counter();
    let ctx = default_ctx();

    // First evaluation: kick, snare, kick, snare
    let f1 = forth_with_counter(counter.clone());
    let outputs1 = f1.evaluate(r#"| "kick" "snare" | s . ."#, &ctx).unwrap();
    let sounds1 = get_sounds(&outputs1);
    assert_eq!(sounds1, vec!["kick", "snare"]);

    // Second evaluation: continues from where we left off
    let f2 = forth_with_counter(counter.clone());
    let outputs2 = f2.evaluate(r#"| "kick" "snare" | s . ."#, &ctx).unwrap();
    let sounds2 = get_sounds(&outputs2);
    assert_eq!(sounds2, vec!["kick", "snare"]);
}

#[test]
fn persistent_counter_three_item_cycle() {
    let counter = new_emission_counter();
    let ctx = default_ctx();

    // First eval: kick, snare
    let f1 = forth_with_counter(counter.clone());
    let outputs1 = f1.evaluate(r#"| "kick" "snare" "hat" | s . ."#, &ctx).unwrap();
    let sounds1 = get_sounds(&outputs1);
    assert_eq!(sounds1, vec!["kick", "snare"]);

    // Second eval: continues from hat (index 2)
    let f2 = forth_with_counter(counter.clone());
    let outputs2 = f2.evaluate(r#"| "kick" "snare" "hat" | s . ."#, &ctx).unwrap();
    let sounds2 = get_sounds(&outputs2);
    assert_eq!(sounds2, vec!["hat", "kick"]);

    // Third eval: snare, hat
    let f3 = forth_with_counter(counter.clone());
    let outputs3 = f3.evaluate(r#"| "kick" "snare" "hat" | s . ."#, &ctx).unwrap();
    let sounds3 = get_sounds(&outputs3);
    assert_eq!(sounds3, vec!["snare", "hat"]);
}

#[test]
fn emit_n_with_persistent_counter() {
    let counter = new_emission_counter();
    let ctx = default_ctx();

    // First eval: 3 emits from a 4-item cycle
    let f1 = forth_with_counter(counter.clone());
    let outputs1 = f1.evaluate(r#"| "a" "b" "c" "d" | s 3 .!"#, &ctx).unwrap();
    let sounds1 = get_sounds(&outputs1);
    assert_eq!(sounds1, vec!["a", "b", "c"]);

    // Second eval: continues from d
    let f2 = forth_with_counter(counter.clone());
    let outputs2 = f2.evaluate(r#"| "a" "b" "c" "d" | s 3 .!"#, &ctx).unwrap();
    let sounds2 = get_sounds(&outputs2);
    assert_eq!(sounds2, vec!["d", "a", "b"]);
}