#!/bin/bash
set -euo pipefail

read_index() {
    if [ -f "$INDEX_FILE" ]; then
        cat "$INDEX_FILE"
    else
        echo '{"base": null, "pm_agent": null, "issues": {}}'
    fi
}

write_index() {
    local base="$1"
    local pm_agent="$2"
    local issues_json="$3"
    local temp_file="$INDEX_FILE.tmp.$$"
    printf '{"base": %s, "pm_agent": %s, "issues": %s}\n' "$base" "$pm_agent" "$issues_json" > "$temp_file"
    mv "$temp_file" "$INDEX_FILE"
}

get_base_session_id() {
    local index=$(read_index)
    echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(d.get('base') or '')"
}

get_pm_agent_session_id() {
    local index=$(read_index)
    echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(d.get('pm_agent') or '')"
}

get_session_for_issue() {
    local issue_ref="$1"
    local index=$(read_index)
    echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(d.get('issues', {}).get('$issue_ref') or 'null')"
}

set_base_in_index() {
    local session_id="$1"
    local index=$(read_index)
    local pm_agent=$(echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(d.get('pm_agent') or 'null')")
    local issues=$(echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(json.dumps(d.get('issues', {})))")
    
    if [ "$session_id" = "null" ]; then
        write_index "null" "$pm_agent" "$issues"
    else
        write_index "\"$session_id\"" "$pm_agent" "$issues"
    fi
}

set_pm_agent_in_index() {
    local session_id="$1"
    local index=$(read_index)
    local base=$(echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(d.get('base') or 'null')")
    local issues=$(echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(json.dumps(d.get('issues', {})))")
    
    if [ "$session_id" = "null" ]; then
        write_index "$base" "null" "$issues"
    else
        write_index "$base" "\"$session_id\"" "$issues"
    fi
}

add_issue_to_index() {
    local issue_ref="$1"
    local session_file="$2"
    
    local index=$(read_index)
    local base=$(echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(d.get('base') or 'null')")
    local pm_agent=$(echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(d.get('pm_agent') or 'null')")
    
    local issues=$(echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(json.dumps(d.get('issues', {})))")
    
    issues=$(python3 -c "import sys, json; d=json.load(sys.stdin); d['$issue_ref']='$session_file'; print(json.dumps(d))" <<< "$issues")
    
    write_index "$base" "$pm_agent" "$issues"
}

remove_issue_from_index() {
    local issue_ref="$1"
    
    local index=$(read_index)
    local base=$(echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(d.get('base') or 'null')")
    local pm_agent=$(echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(d.get('pm_agent') or 'null')")
    
    local issues=$(echo "$index" | python3 -c "import sys, json; d=json.load(sys.stdin); print(json.dumps(d.get('issues', {})))")
    
    issues=$(python3 -c "import sys, json; d=json.load(sys.stdin); d.pop('$issue_ref', None); print(json.dumps(d))" <<< "$issues")
    
    write_index "$base" "$pm_agent" "$issues"
}

validate_issue_ref() {
    local issue_ref="$1"
    
    if [[ ! "$issue_ref" =~ ^[a-zA-Z0-9.-]+/[a-zA-Z0-9._-]+/[a-zA-Z0-9._-]+#[0-9]+$ ]]; then
        echo "Error: Invalid issue ref format: '$issue_ref'" >&2
        echo "Expected format: instance/user/repo#number" >&2
        echo "Example: github.com/shoko/kugetsu#14" >&2
        exit 1
    fi
}

update_session_pr_url() {
    local issue_ref="$1"
    local pr_url="$2"
    
    local session_file=$(get_session_for_issue "$issue_ref")
    if [ -z "$session_file" ] || [ "$session_file" = "null" ]; then
        echo "Error: No session found for '$issue_ref'" >&2
        return 1
    fi
    
    local session_path="$SESSIONS_DIR/$session_file"
    if [ ! -f "$session_path" ]; then
        echo "Error: Session file not found: $session_path" >&2
        return 1
    fi
    
    python3 << PYEOF
import json

session_path = "$session_path"
pr_url = "$pr_url"

with open(session_path, 'r') as f:
    session = json.load(f)

session['pr_url'] = pr_url

with open(session_path, 'w') as f:
    json.dump(session, f, indent=2)

print(f"Updated PR URL for $issue_ref: $pr_url")
PYEOF
}