#!/usr/bin/env bash
# lib/assert.sh — assertions that record evidence per the spec.
#
# Each assertion appends one record to:
#   $PROOF_REPORT_DIR/raw/cases/<case_id>.jsonl
#
# Each line is a self-describing JSON object — case ID, claim, expected,
# actual, result {pass|fail|skip}, optional evidence pointers. Cases
# call multiple assertions; run_proof.sh aggregates JSONL → summary.
#
# Functions:
#   proof_assert_eq        <case_id> <claim> <expected> <actual>
#   proof_assert_ne        <case_id> <claim> <not_expected> <actual>
#   proof_assert_contains  <case_id> <claim> <substring> <haystack>
#   proof_assert_lt        <case_id> <claim> <a> <b>          # passes if a < b
#   proof_assert_gt        <case_id> <claim> <a> <b>          # passes if a > b
#   proof_assert_status    <case_id> <claim> <expected_status> <probe_name>
#   proof_assert_json_eq   <case_id> <claim> <jq_path> <expected> <body_or_file>
#   proof_skip             <case_id> <claim> <reason>
#
# All return 0 (case scripts decide their own halt-on-fail policy).

_proof_record() {
    local case_id="$1" claim="$2" result="$3" expected="$4" actual="$5" detail="$6"
    local out="${PROOF_REPORT_DIR}/raw/cases/${case_id}.jsonl"
    mkdir -p "$(dirname "$out")"
    # JSON-escape the variable inputs.
    local e_claim e_expected e_actual e_detail
    e_claim=$(printf '%s' "$claim"       | jq -Rs .)
    e_expected=$(printf '%s' "$expected" | jq -Rs .)
    e_actual=$(printf '%s' "$actual"     | jq -Rs .)
    e_detail=$(printf '%s' "$detail"     | jq -Rs .)
    local ts
    ts=$(date -u -Iseconds)
    cat >> "$out" <<JSON
{"case_id":"${case_id}","claim":${e_claim},"result":"${result}","expected":${e_expected},"actual":${e_actual},"detail":${e_detail},"timestamp":"${ts}","git_sha":"${PROOF_GIT_SHA}"}
JSON
}

proof_assert_eq() {
    local case_id="$1" claim="$2" expected="$3" actual="$4"
    if [ "$expected" = "$actual" ]; then
        _proof_record "$case_id" "$claim" pass "$expected" "$actual" ""
        return 0
    fi
    _proof_record "$case_id" "$claim" fail "$expected" "$actual" "values differ"
    return 0
}

proof_assert_ne() {
    local case_id="$1" claim="$2" not_expected="$3" actual="$4"
    if [ "$not_expected" != "$actual" ]; then
        _proof_record "$case_id" "$claim" pass "!= ${not_expected}" "$actual" ""
        return 0
    fi
    _proof_record "$case_id" "$claim" fail "!= ${not_expected}" "$actual" "values matched (should differ)"
    return 0
}

proof_assert_contains() {
    local case_id="$1" claim="$2" substring="$3" haystack="$4"
    if [[ "$haystack" == *"$substring"* ]]; then
        _proof_record "$case_id" "$claim" pass "contains: ${substring}" "$haystack" ""
        return 0
    fi
    _proof_record "$case_id" "$claim" fail "contains: ${substring}" "$haystack" "substring not found"
    return 0
}

proof_assert_lt() {
    local case_id="$1" claim="$2" a="$3" b="$4"
    # awk handles ints + floats uniformly
    if awk -v a="$a" -v b="$b" 'BEGIN{exit !(a < b)}'; then
        _proof_record "$case_id" "$claim" pass "${a} < ${b}" "${a}" ""
        return 0
    fi
    _proof_record "$case_id" "$claim" fail "${a} < ${b}" "${a}" "${a} is not less than ${b}"
    return 0
}

proof_assert_gt() {
    local case_id="$1" claim="$2" a="$3" b="$4"
    if awk -v a="$a" -v b="$b" 'BEGIN{exit !(a > b)}'; then
        _proof_record "$case_id" "$claim" pass "${a} > ${b}" "${a}" ""
        return 0
    fi
    _proof_record "$case_id" "$claim" fail "${a} > ${b}" "${a}" "${a} is not greater than ${b}"
    return 0
}

# proof_assert_status compares the status from a previously-recorded
# probe against an expected value. Probe must have run via lib/http.sh.
proof_assert_status() {
    local case_id="$1" claim="$2" expected="$3" probe_name="$4"
    local actual
    actual=$(proof_status_of "$case_id" "$probe_name" 2>/dev/null || echo missing)
    proof_assert_eq "$case_id" "$claim" "$expected" "$actual"
}

# proof_assert_json_eq: jq-based equality on response body or a file.
# body_or_file: if starts with @, read from file; otherwise treat as
# literal JSON string.
proof_assert_json_eq() {
    local case_id="$1" claim="$2" jq_path="$3" expected="$4" source="$5"
    local actual
    if [[ "$source" == @* ]]; then
        actual=$(jq -r "$jq_path" "${source#@}" 2>/dev/null || echo "<jq error>")
    else
        actual=$(printf '%s' "$source" | jq -r "$jq_path" 2>/dev/null || echo "<jq error>")
    fi
    proof_assert_eq "$case_id" "$claim" "$expected" "$actual"
}

proof_skip() {
    local case_id="$1" claim="$2" reason="$3"
    _proof_record "$case_id" "$claim" skip "" "" "$reason"
    return 0
}

# proof_assert_status_in: pass if probe's status is in the space-separated
# expected list. Use when a route legitimately has multiple OK codes (e.g.
# 200 vs 204 vs 201 across services). Records a clean pass/fail with the
# actual status echoed back.
proof_assert_status_in() {
    local case_id="$1" claim="$2" expected_list="$3" probe="$4"
    local actual found
    actual=$(proof_status_of "$case_id" "$probe" 2>/dev/null || echo missing)
    found=0
    for ok in $expected_list; do
        [ "$ok" = "$actual" ] && { found=1; break; }
    done
    if [ "$found" = 1 ]; then
        _proof_record "$case_id" "$claim" pass "in {${expected_list}}" "$actual" ""
    else
        _proof_record "$case_id" "$claim" fail "in {${expected_list}}" "$actual" "status not in expected list"
    fi
    return 0
}

# proof_assert_status_4xx: pass if probe's status is in [400, 500). Use
# for failure-mode contracts where the specific 4xx code is allowed to
# vary (400 vs 422 vs 409) — only "is a client error" matters.
proof_assert_status_4xx() {
    local case_id="$1" claim="$2" probe="$3"
    local actual
    actual=$(proof_status_of "$case_id" "$probe" 2>/dev/null || echo missing)
    if awk -v s="$actual" 'BEGIN{exit !(s+0 >= 400 && s+0 < 500)}'; then
        _proof_record "$case_id" "$claim" pass "4xx" "$actual" ""
    else
        _proof_record "$case_id" "$claim" fail "4xx" "$actual" "status is not in 400-499"
    fi
    return 0
}
